Research Publications

November 2022

Hazany S, Nguyen KL, Lee M, Zhang A, Mokhtar P, Crossley A, Luthra S, Butani P, Dergalust S, Ellingson B, Hinman JD.

BACKGROUND: Current methods for quantitative assessment of cerebral small vessel disease (CSVD) ignore critical aspects of the disease, namely lesion type and regionality. We developed and tested a new scoring system for CSVD, "regional Cerebral Small Vessel Disease" (rCSVD) based on regional assessment of magnetic resonance imaging (MRI) features. METHODS: 141 patients were retrospectively included with a derivation cohort of 46 consecutive brain MRI exams and a validation cohort of 95 patients with known cerebrovascular disease. We compared the predictive value of rCSVD against existing scoring methods. We determined the predictive value of rCSVD score for all-cause mortality and recurrent strokes.

November 2022

Hsu W, Hippe DS, Nakhaei N, Wang PC, Zhu B, Siu N, Ahsen ME, Lotter W, Sorensen AG, Naeim A, Buist DSM, Schaffter T, Guinney J, Elmore JG, Lee CI.

IMPORTANCE: With a shortfall in fellowship-trained breast radiologists, mammography screening programs are looking toward artificial intelligence (AI) to increase efficiency and diagnostic accuracy. External validation studies provide an initial assessment of how promising AI algorithms perform in different practice settings. OBJECTIVE: To externally validate an ensemble deep-learning model using data from a high-volume, distributed screening program of an academic health system with a diverse patient population. DESIGN, SETTING, & PARTICIPANTS: In this diagnostic study, an ensemble learning method, which reweights outputs of the 11 highest-performing individual AI models from the Digital Mammography Dialogue on Reverse Engineering Assessment and Methods (DREAM) Mammography Challenge, was used to predict the cancer status of an individual using a standard set of screening mammography images. This study was conducted using retrospective patient data collected between 2010 and 2020 from women aged 40 years and older who underwent a routine breast screening examination and participated in the Athena Breast Health Network at the University of California, Los Angeles (UCLA). MAIN OUTCOMES & MEASURES: Performance of the challenge ensemble method (CEM) and the CEM combined with radiologist assessment (CEM+R) were compared with diagnosed ductal carcinoma in situ and invasive cancers within a year of the screening examination using performance metrics, such as sensitivity, specificity, and area under the receiver operating characteristic curve (AUROC).

November 2022

Oh JH, Kim GHJ, Cross G, Barnett J, Jacob J, Hong S, Song JW.

OBJECTIVE: The prognosis of RA-associated interstitial lung disease (RA-ILD) is difficult to predict because of the variable clinical course. This study aimed to determine the prognostic value of an automated quantification system (AQS) in RA-ILD. METHODS: We retrospectively analysed the clinical data and high-resolution CT (HRCT) images of 144 patients with RA-ILD. Quantitative lung fibrosis (QLF, sum of reticulation and traction bronchiectasis) and ILD [QILD; sum of QLF, honeycombing (QHC), and ground-glass opacity (QGG)] scores were measured using the AQS.

November 2022

Padhani AR, Raman SS, Schoots IG.

There are many reasons why MRI-targeted biopsies (MRTB) in men with positive MRI scans fail to detect high-grade cancers that are found incidentally by concurrent systemic biopsies. Multiple factors often acting together contribute to the missed diagnoses of ISUP GG ≥ 2 cancers and/or tumour under grading [1]. The most obvious cause is an MRI invisible lesion on a background of transition zone hyperplasia, peripheral zone scarring/inflammation, or in difficult to evaluate regions such as adjacency to the ejaculatory ducts, central zone, bladder, low apex, or the anterior fibromuscular stroma. Some histologic subtypes of GG ≥ 2 prostate cancers are also difficult to see such as non-mass forming (microfocal) GG2 cancers and small cribriform tumours. Inevitably, radiologic perception errors also contribute, related to image quality, observer experience and variability, and misclassifications errors.

November 2022

Zheng HW, Ranganath VK, Perry LC, Chetrit DA, Criner KM, Pham AQ, Seto R, Vangala S, Elashoff DA, Bui AAT.

To better understand the challenges of generally implementing and adapting computational phenotyping approaches, the performance of a Phenotype KnowledgeBase (PheKB) algorithm for rheumatoid arthritis (RA) was evaluated on a University of California, Los Angeles (UCLA) patient population, focusing on examining its performance on ambiguous cases. The algorithm was evaluated on a cohort of 4,766 patients, along with a chart review of 300 patients by rheumatologists against accepted diagnostic guidelines. The performance revealed low sensitivity towards specific subtypes of positive RA cases, which suggests revisions in features used for phenotyping. A close examination of select cases also indicated a significant portion of patients with missing data, drawing attention to the need to consider data integrity as an integral part of phenotyping pipelines, as well as issues around the usability of various codes for distinguishing cases. We use patterns in the PheKB algorithm's errors to further demonstrate important considerations when designing a phenotyping algorithm.

October 2022

Bath EP, Brown K, Harris C, Guerrero A, Kozman D, Flippen CC 2nd, Garraway I, Watson K, Holly L, Godoy SM, Norris K, Wyatt G.

The woefully low proportion of scientists and clinicians underrepresented in medicine (UIM), including members of African-American/Black, Hispanic/Latinx, American Indian/Alaska Native or Native Hawaiian/Pacific Islander communities, is well characterized and documented. Diversity in medicine is not only just, but it improves quality and outcomes. Yet, diversity in academic medicine remains stagnant, despite national recognition and urgent calls to improve diversity, equity, and inclusion across health sciences. One strategy that has shown to improve diversity in many sectors is high quality mentoring. While many institutions have adopted mentoring programs, there remains a lack of mentorship that is equitable, individualized, and sets a clear timeline for academic milestones that will position UIM mentees at the optimal trajectory for promotion and retention. A barrier to assembling these programs is the small number of UIM among the senior faculty ranks who are able to serve in this role, given the disproportionate burden to serve on a multitude of academic committees, task forces, and workgroups to fulfill institutional mandates to diversify representation. These time-consuming services, documented in the literature as the "minority tax," are generally uncompensated and unaccounted for in terms of consideration for promotion, leadership positions, and other measures of career advancement. The Justice, Equity, Diversity, and Inclusion Academic Mentors (JAM) Council represents a novel, culturally responsive, and anti-racist approach to achieve a more equitable and inclusive institutional environment. This approach strategically leverages the intergenerational wisdom and experience of senior UIM faculty via time-protected effort with the overall goals of improving rates of promotion, retention, and career satisfaction of early career UIM colleagues. This community case study describes the rationale, resources needed, processes, and proposed workflow required to launch the JAM Council, as well as the major roles and responsibilities for JAM mentors and mentees, which may be considered by academic medical centers focused on improving diversity among the faculty ranks.

October 2022

Enzmann DR.

Inspired by the "Green New Deal," diagnostic radiology (DxR) should design and adopt a "Smart New Deal;" "smart" as in smartphones. DxR would be wise to follow Wayne Gretzky's advice, "... skate to where the puck will be." That puck is the sophisticated mobile, small-screen communication device in the form of smartphones, tablets, iPads, etc. In this article, for brevity, "smartphone" is used as shorthand for those well-honed devices which combine compact, sturdy hardware (H/W) with integrated, intelligent software (S/W). Smartphones are an essential professional accoutrement tucked into purses, sport coats, or jean pockets. Ubiquitous smartphones communicate information, establish relationships, and shape healthcare experiences.

October 2022

Hendrix N, Lowry KP, Elmore JG, Lotter W, Sorensen G, Hsu W, Liao GJ, Parsian S, Kolb S, Naeim A, Lee CI.

BACKGROUND: Artificial intelligence (AI) may improve cancer detection and risk prediction during mammography screening, but radiologists' preferences regarding its characteristics and implementation are unknown. PURPOSE: To quantify how different attributes of AI-based cancer detection and risk prediction tools affect radiologists' intentions to use AI during screening mammography interpretation. MATERIALS & METHODS: Through qualitative interviews with radiologists, we identified five primary attributes for AI-based breast cancer detection and four for breast cancer risk prediction. We developed a discrete choice experiment based on these attributes and invited 150 US-based radiologists to participate. Each respondent made eight choices for each tool between three alternatives: two hypothetical AI-based tools versus screening without AI. We analyzed samplewide preferences using random parameters logit models and identified subgroups with latent class models.

October 2022

Jamshidi N, Nigam SK.

In vitro and in vivo studies have established the organic anion transporters OAT1 (SLC22A6, NKT) and OAT3 (SLC22A8) among the main multi-specific "drug" transporters. They also transport numerous endogenous metabolites, raising the possibility of drug-metabolite interactions (DMI). To help understand the role of these drug transporters on metabolism across scales ranging from organ systems to organelles, a formal multi-scale analysis was performed. Metabolic network reconstructions of the omics-alterations resulting from Oat1 and Oat3 gene knockouts revealed links between the microbiome and human metabolism including reactions involving small organic molecules such as dihydroxyacetone, alanine, xanthine, and p-cresol-key metabolites in independent pathways. Interestingly, pairwise organ-organ interactions were also disrupted in the two Oat knockouts, with altered liver, intestine, microbiome, and skin-related metabolism. Compared to older models focused on the "one transporter-one organ" concept, these more sophisticated reconstructions, combined with integration of a multi-microbial model and more comprehensive metabolomics data for the two transporters, provide a considerably more complex picture of how renal "drug" transporters regulate metabolism across the organelle (e.g. endoplasmic reticulum, Golgi, peroxisome), cellular, organ, inter-organ, and inter-organismal scales. The results suggest that drugs interacting with OAT1 and OAT3 can have far reaching consequences on metabolism in organs (e.g. skin) beyond the kidney. Consistent with the Remote Sensing and Signaling Theory (RSST), the analysis demonstrates how transporter-dependent metabolic signals mediate organ crosstalk (e.g., gut-liver-kidney) and inter-organismal communication (e.g., gut microbiome-host).

October 2022

Khanna D, Distler O, Cottin V, Brown KK, Chung L, Goldin JG, Matteson EL, Kazerooni EA, Walsh SL, McNitt-Gray M, Maher TM.

Patients with systemic sclerosis are at high risk of developing systemic sclerosis-associated interstitial lung disease. Symptoms and outcomes of systemic sclerosis-associated interstitial lung disease range from subclinical lung involvement to respiratory failure and death. Early and accurate diagnosis of systemic sclerosis-associated interstitial lung disease is therefore important to enable appropriate intervention. The most sensitive and specific way to diagnose systemic sclerosis-associated interstitial lung disease is by high-resolution computed tomography, and experts recommend that high-resolution computed tomography should be performed in all patients with systemic sclerosis at the time of initial diagnosis. In addition to being an important screening and diagnostic tool, high-resolution computed tomography can be used to evaluate disease extent in systemic sclerosis-associated interstitial lung disease and may be helpful in assessing prognosis in some patients. Currently, there is no consensus with regards to frequency and scanning intervals in patients at risk of interstitial lung disease development and/or progression. However, expert guidance does suggest that frequency of screening using high-resolution computed tomography should be guided by risk of developing interstitial lung disease. Most experienced clinicians would not repeat high-resolution computed tomography more than once a year or every other year for the first few years unless symptoms arose. Several computed tomography techniques have been developed in recent years that are suitable for regular monitoring, including low-radiation protocols, which, together with other technologies, such as lung ultrasound and magnetic resonance imaging, may further assist in the evaluation and monitoring of patients with systemic sclerosis-associated interstitial lung disease.

October 2022

Roubakha M, Homer R.

Diffuse idiopathic skeletal hyperostosis (DISH) is noninflammatory flowing, bridging ossification of the anterior longitudinal ligament in at least four contiguous segments. This type of ossification is nonmarginal becauseit protrudes beyond the vertebral bodies. The intervertebral disks are preserved.Diffuse idiopathic skeletal hyperostosis is typically diagnosed in the sixth and the seventh decades oflife, is often associated with diabetes and obesity, and affects predominantly men.

October 2022

Shi BY, Levine B, Ghazikhanian V, Bugarin A, Schroeder G, Wu S, Kremen T, Jones K.

BACKGROUND: While studies have described Kaplan fiber (KF) injury in up to 60% of adults with anterior cruciate ligament (ACL) tears, the incidence of KF injury in the pediatric and adolescent population remains unknown. PURPOSE: To (1) determine the reliability of using magnetic resonance imaging (MRI) to identify KF injury in the pediatric and adolescent population and (2) define the incidence of KF injury in these patients with acute ACL injuries. STUDY DESIGN: Cohort study (diagnosis); Level of evidence, 3. METHODS: The authors retrospectively identified patients ≤18 years of age who underwent ACL reconstruction for acute tears between 2013 and 2020. All preoperative MRI scans were reviewed independently and in a blinded fashion by 2 musculoskeletal radiologists, who noted the presence of the KF complex and any evidence of injury; interrater reliability was assessed. Patient characteristics, time from injury to MRI, laterality, and concomitant ligamentous or meniscal injuries were recorded, and associations between patient or injury characteristics and KF integrity on MRI were assessed.

October 2022

Shidoh S, Savjani RR, Cho NS, Ullman HE, Hagiwara A, Raymond C, Lai A, Nghiemphu PL, Liau LM, Pope WB, Cloughesy TF, Kaprealian TB, Salamon N, Ellingson BM.

PURPOSE: To quantify the radiation dose distribution and lesion morphometry (shape) at baseline, prior to chemoradiation, and at the time of radiographic recurrence in patients with glioblastoma (GBM). METHODS: The IMRT dose distribution, location of the center of mass, sphericity, and solidity of the contrast enhancing tumor at baseline and the time of tumor recurrence was quantified in 48 IDH wild-type GBM who underwent postoperative IMRT (2 Gy daily for total of 60 Gy) with concomitant and adjuvant temozolomide.

October 2022

Szabari MV, Lau CT.

Lipoid pneumonia (LP) is an uncommon condition caused by accumulation of lipids in the lungs. Patients with LP may present either with no symptoms or with nonspecific symptoms, such as dyspnea and cough. Lipoid pneumonia typically arises from the aspiration of fatty substances (exogenous LP) or the aggregation of lipid-rich debris from damaged lung tissue (endogenous LP). Recently, cases of LP arising from e-cigarette usehave been reported.

October 2022

Wang C, Ellingson BM, Oughourlian TC, Salamon N, Holly LT.

BACKGROUND: Advanced imaging modalities have helped elucidate the cerebral alterations associated with neurological impairment caused by degenerative cervical myelopathy (DCM), but it remains unknown how brain functional network changes at different stages of myelopathy severity in DCM patients, and if patterns in network connectivity can be used to predict transition to more myelopathic stages of DCM. METHODS: This pilot cross-sectional study, which involves the collection of resting-state functional MRI (rs-fMRI) images and the modified Japanese Orthopedic Association (mJOA) score, enrolled 116 participants (99 patients and 17 healthy controls) from 2016 to 2021. The patient cohort included 21patients with asymptomatic spinal cord compression, 48 mild DCM patients, and 20 moderate or severe DCM patients. Functional connectivity networks were quantified for all participants, and the transition matrices were quantified to determine the differences in network connectivity through increasingly myelopathic stages of DCM. Additionally, a link prediction model was used to determine whether more severe stages of DCM can be predicted from less symptomatic stages using the transition matrices.

October 2022

Zhang T, Chen M, Bui AAT.

Early detection of heart failure (HF) can provide patients with the opportunity for more timely intervention and better disease management, as well as efficient use of healthcare resources. Recent machine learning (ML) methods have shown promising performance on diagnostic prediction using temporal sequences from electronic health records (EHRs). In practice, however, these models may not generalize to other populations due to dataset shift. Shifts in datasets can be attributed to a range of factors such as variations in demographics, data management methods, and healthcare delivery patterns. In this paper, we use unsupervised adversarial domain adaptation methods to adaptively reduce the impact of dataset shift on cross-institutional transfer performance. The proposed framework is validated on a next-visit HF onset prediction task using a BERT-style Transformer-based language model pre-trained with a masked language modeling (MLM) task. Our model empirically demonstrates superior prediction performance relative to non-adversarial baselines in both transfer directions on two different clinical event sequence data sources.

September 2022

Brossard P, Ledbetter L.

Right lower quadrant (RLQ) abdominal pain accounts for nearly 50% of patients who go to the emergency department with abdominal pain. Appendicitis is the most common reason for RLQ pain in the United States requiring surgery.

September 2022

Hagiwara A, Schlossman J, Shabani S, Raymond C, Tatekawa H, Abrey LE, Garcia J, Chinot O, Saran F, Nishikawa R, Henriksson R, Mason WP, Wick W, Cloughesy TF, Ellingson BM.

PURPOSE: Pseudoprogression (PsP) remains an elusive and clinically important, yet ill-defined, phenomena that, generally, involves a period of early radiographic progression (enhancement) followed by a period of radiographic stability or regression. In the current study, we utilized data from the control arm of a phase III clinical trial in newly-diagnosed glioblastoma to explore imaging characteristics of "clinically-defined PsP", or early radiographic progression (PFS < 6 months from chemoradiation) followed by a long post-progression residual overall survival (ROS > 12 months). METHODS: One hundred sixty-nine patients with newly-diagnosed GBM from the control arm of the AVAglio trial (NCT00943826) who presented with early radiographic progressive disease (PD) (< 6 months) were included. Clinical characteristics, topographical patterns, and radiomic features were compared between newly-diagnosed GBM exhibiting early PD and early death (< 12-month ROS, "true PD") with those exhibiting early PD and a long residual survival (> 12-month ROS, "clinically-defined PsP").

September 2022

Joo I, Morrow KW, Raman SS, McWilliams JP, Sayre JW, Lu DS.

OBJECTIVES: To investigate the usefulness of minimal ablative margin (MAM) control by intra-procedural contrast-enhanced CT (CECT) in microwave ablation (MWA) of liver tumors. METHODS: A total of 334 consecutive liver tumors (240 hepatocellular carcinomas [HCCs] and 94 colorectal liver metastases [CRLMs]) in 172 patients treated with percutaneous MWA were retrospectively included. MAM of each tumor was assessed after expected ablation completion using intra-procedural CECT, allowing within-session additional ablation to any potentially insufficient margin. On immediate post-MWA MRI, complete ablation coverage of tumor and final MAM status were determined. The cumulative local tumor progression (LTP) rate was estimated by using the Kaplan-Meier method. To identify predictors of LTP, Cox regression analysis with a shared frailty model was performed.

September 2022

Kao SD, Padia SA, Moriarty JM, Srinivasa RN.

Renal cell carcinomas present with locally advanced or metastatic disease in 25% of patients. Thermal ablation may be considered in selected patients with single-site or oligometastatic disease in selected patients. We describe single-session transarterial particle embolization with the assistance of a balloon-occlusion catheter and microwave ablation of a large hypervascular adrenal metastasis using cone beam CT and fluoroscopic XperGuide needle guidance.

September 2022

Kerr WT, Tatekawa H, Lee JK, Karimi AH, Sreenivasan SS, O'Neill J, Smith JM, Hickman LB, Savic I, Nasrullah N, Espinoza R, Narr K, Salamon N, Beimer NJ, Hadjiiski LM, Eliashiv DS, Stacey WC, Engel J Jr, Feusner JD, Stern JM.

PURPOSE: Functional seizures (FS), also known as psychogenic nonepileptic seizures (PNES), are physical manifestations of acute or chronic psychological distress. Functional and structural neuroimaging have identified objective signs of this disorder. We evaluated whether magnetic resonance imaging (MRI) morphometry differed between patients with FS and clinically relevant comparison populations. METHODS: Quality-screened clinical-grade MRIs were acquired from 666 patients from 2006 to 2020. Morphometric features were quantified with FreeSurfer v6. Mixed-effects linear regression compared the volume, thickness, and surface area within 201 regions-of-interest for 90 patients with FS, compared to seizure–naïve patients with depression (n = 243), anxiety (n = 68), and obsessive-compulsive disorder (OCD, n = 41), respectively, and to other seizure–naïve controls with similar quality MRIs, accounting for the influence of multiple confounds including depression and anxiety based on chart review. These comparison populations were obtained through review of clinical records plus research studies obtained on similar scanners.

September 2022

Senthilvelan J, Jamshidi N.

Multiple studies have created state-of-the-art liver segmentation models using Deep Convolutional Neural Networks (DCNNs) such as the V-net and H-DenseUnet. Oversegmentation however continues to be a problem. We set forth to address these limitations by developing a an automated workflow that leverages the strengths of different DCNN architectures, resulting in a pipeline that enables fully automated liver segmentation. A Pipeline for Automated Deep Learning Liver Segmentation (PADLLS) was developed and implemented that cascades multiple DCNNs that were trained on more than 200 CT scans. First, a V-net is used to create a rough liver, spleen, and stomach mask. After stomach and spleen pixels are removed using their respective masks and ascites is removed using a morphological algorithm, the scan is passed to a H-DenseUnet to yield the final segmentation. The segmentation accuracy of the pipleline was compared to the H-DenseUnet and the V-net using the SLIVER07 and 3DIRCADb datasets as benchmarks.

September 2022

Stackpole ML, Zeng W, Li S, Liu CC, Zhou Y, He S, Yeh A, Wang Z, Sun F, Li Q, Yuan Z, Yildirim A, Chen PJ, Winograd P, Tran B, Lee YT, Li PS, Noor Z, Yokomizo M, Ahuja P, Zhu Y, Tseng HR, Tomlinson JS, Garon E, French S, Magyar CE, Dry S, Lajonchere C, Geschwind D, Choi G, Saab S, Alber F, Wong WH, Dubinett SM, Aberle DR, Agopian V, Han SB, Ni X, Li W, Zhou XJ.

Early cancer detection by cell-free DNA faces multiple challenges: low fraction of tumor cell-free DNA, molecular heterogeneity of cancer, and sample sizes that are not sufficient to reflect diverse patient populations. Here, we develop a cancer detection approach to address these challenges. It consists of an assay, cfMethyl-Seq, for cost-effective sequencing of the cell-free DNA methylome (with > 12-fold enrichment over whole genome bisulfite sequencing in CpG islands), and a computational method to extract methylation information and diagnose patients.

September 2022

Tsui B, Nour M, Chen I, Qiao JX, Salehi B, Yoo B, Colby GP, Salamon N, Villablanca P, Jahan R, Duckwiler G, Saver JL, Liebeskind DS, Nael K.

Collateral status has prognostic and treatment implications in acute ischemic stroke (AIS) patients. Unlike CTA, grading collaterals on MRA is not well studied. We aimed to evaluate the accuracy of assessing collaterals on pretreatment MRA in AIS patients against DSA. AIS patients with anterior circulation proximal arterial occlusion with baseline MRA and subsequent endovascular treatment were included. MRA collaterals were evaluated by two neuroradiologists independently using the Tan and Maas scoring systems. DSA collaterals were evaluated by using the American Society of Interventional and Therapeutic Neuroradiology grading system and were used as the reference for comparative analysis against MRA.

August 2022

Cho NS, Hagiwara A, Eldred BSC, Raymond C, Wang C, Sanvito F, Lai A, Nghiemphu P, Salamon N, Steelman L, Hassan I, Cloughesy TF, Ellingson BM.

BACKGROUND: Inhibition of the isocitrate dehydrogenase (IDH)-mutant enzyme is a novel therapeutic target in IDH-mutant gliomas. Imaging biomarkers of IDH inhibitor treatment efficacy in human IDH-mutant gliomas are largely unknown. This study investigated early volumetric, perfusion, and diffusion MRI changes in IDH1-mutant gliomas during IDH inhibitor treatment. METHODS: Twenty-nine IDH1-mutant glioma patients who received IDH inhibitor and obtained anatomical, perfusion, and diffusion MRI pretreatment at 3-6 weeks (n = 23) and/or 2-4 months (n = 14) of treatment were retrospectively studied. Normalized relative cerebral blood volume (nrCBV), apparent diffusion coefficient (ADC), and fluid-attenuated inversion recovery (FLAIR) hyperintensity volume were analyzed.

August 2022

Ellingson BM, Gerstner ER, Lassman AB, Chung C, Colman H, Cole PE, Leung D, Allen JE, Ahluwalia MS, Boxerman J, Brown M, Goldin J, Nduom E, Hassan I, Gilbert MR, Mellinghoff IK, Weller M, Chang S, Arons D, Meehan C, Selig W, Tanner K, Alfred Yung WK, van den Bent M, Wen PY, Cloughesy TF.

Imaging response assessment is a cornerstone of patient care and drug development in oncology. Clinicians/clinical researchers rely on tumor imaging to estimate the impact of new treatments and guide decision making for patients and candidate therapies. This is important in brain cancer, where associations between tumor size/growth and emerging neurological deficits are strong. Accurately measuring the impact of a new therapy on tumor growth early in clinical development, where patient numbers are small, would be valuable for decision making regarding late-stage development activation. Current attempts to measure the impact of a new therapy have limited influence on clinical development, as determination of progression, stability or response does not currently account for individual tumor growth kinetics prior to the initiation of experimental therapies. Therefore, we posit that imaging-based response assessment, often used as a tool for estimating clinical effect, is incomplete as it does not adequately account for growth trajectories or biological characteristics of tumors prior to the introduction of an investigational agent. Here, we propose modifications to the existing framework for evaluating imaging assessment in primary brain tumors that will provide a more reliable understanding of treatment effects. Measuring tumor growth trajectories prior to a given intervention may allow us to more confidently conclude whether there is an anti-tumor effect. This updated approach to imaging-based tumor response assessment is intended to improve our ability to select candidate therapies for later-stage development, including those that may not meet currently sought thresholds for "response" and ultimately lead to identification of effective treatments.

August 2022

Goodman-Meza D, Shover CL, Medina JA, Tang AB, Shoptaw S, Bui AAT.

IMPORTANCE: Overdose is one of the leading causes of death in the US; however, surveillance data lag considerably from medical examiner determination of the death to reporting in national surveillance reports. OBJECTIVE: To automate the classification of deaths related to substances in medical examiner data using natural language processing (NLP) and machine learning (ML). DESIGN, SETTING, AND PARTICIPANTS: Diagnostic study comparing different natural language processing and machine learning algorithms to identify substances related to overdose in 10 health jurisdictions in the US from January 1, 2020, to December 31, 2020. Unstructured text from 35 433 medical examiner and coroners' death records was examined.

August 2022

Hall TR, Brown K.

In the 10-year period between the last two U.S. population censuses there have been significant changes in the U.S. population demography. The changes in self-reporting of racial and ethnic identity afforded by the most recent U.S. population census in 2020 have given citizens the opportunity to be represented in ways that truly reflect how they wish to be identified. At the same time, the diversity of the health care workforce in radiology has not reflected a similar change. While there have been small incremental changes for underrepresented groups (African Americans/Blacks, Hispanic ethnicity, and the group American Indian/Alaska Native/Native Hawaiian/Pacific Islander), these changes have not kept pace with the ever-changing demographics of the U.S. population. Part of the answer for these very modest gains must lie with our selection processes for identifying potential candidates from underrepresented in medicine groups (URiM) for acceptance to our medical schools, residency programs and employment opportunities as practicing physicians and faculty members. While the strategies employed have had some measure of success, our best efforts to increase diversity in our specialty, and in medicine in general, are being undermined by our biases and our traditional methods for identifying talents.

August 2022

Hosseiny M, Sung KH, Felker E, Suvannarerg V, Tubtawee T, Shafa A, Arora KR, Ching J, Gulati A, Azadikhah A, Zhong X, Sayre J, Lu D, Raman SS.

OBJECTIVE: We aimed to investigate if the use of read-out segmented echoplanar imaging with additional two-dimensional navigator correction (Readout Segmentation of Long Variable Echo, RESOLVE) for acquiring prostate diffusion-weighted imaging (DWI) improves image quality, compared to single-shot echoplanar imaging (ss-EPI). METHODS: This single-center prospective study cohort included 162 males with suspected prostate cancer, who underwent 3 Tesla multiparametric MRI (3T-mpMRI). Two abdominal radiologists, blinded to the clinical information, separately reviewed each 3T-mpMRI study to rank geometrical distortion, degree of rectal distention, lesion conspicuity, and anatomic details delineation first on ss-EPI-DWI and later on RESOLVE-DWI using 5-point scales (1 = excellent, 5 = poor). The average of the ranking scores given by two readers was generated and used as the final score.

August 2022

Jalili MH, Yu T, Hassani C, Prosper AE, Finn JP, Bedayat A.

Vascular imaging can be challenging because of the wide variability of contrast dynamics in different vascular territories and potential safety concerns in patients with renal insufficiency or allergies. Off-label diagnostic use of ferumoxytol, a superparamagnetic iron nanoparticle approved for therapy, is a promising alternative to gadolinium-based contrast agents for MR angiography (MRA). Ferumoxytol has exhibited a reassuring safety profile when used within the dose range recommended for diagnostic imaging. Because of its prolonged and stable intravascular residence, ferumoxytol can be used in its steady-state distribution for a wide variety of imaging indications, including some where conventional MRA is unreliable. In this article, authors discuss some of the major vascular applications of ferumoxytol and highlight how it may be used to provide highly diagnostic images and improve the quality, workflow, and reliability of vascular imaging.

August 2022

Joy A, Nagarajan R, Saucedo A, Iqbal Z, Sarma MK, Wilson N, Felker E, Reiter RE, Raman SS, Thomas MA.

OBJECTIVES: This study aimed at developing dictionary learning (DL) based compressed sensing (CS) reconstruction for randomly undersampled five-dimensional (5D) MR Spectroscopic Imaging (3D spatial + 2D spectral) data acquired in prostate cancer patients and healthy controls, and test its feasibility at 8x and 12x undersampling factors. MATERIALS AND METHODS: Prospectively undersampled 5D echo-planar J-resolved spectroscopic imaging (EP-JRESI) data were acquired in nine prostate cancer (PCa) patients and three healthy males. The 5D EP-JRESI data were reconstructed using DL and compared with gradient sparsity-based Total Variation (TV) and Perona-Malik (PM) methods. A hybrid reconstruction technique, Dictionary Learning-Total Variation (DLTV), was also designed to further improve the quality of reconstructed spectra.

August 2022

Kallini JR, Moriarty JM.

The concept of artificial intelligence (AI) elicits futuristic images in the minds of many, perhaps reminding them of films about dystopian worlds. References to AI go back to the 1950s when British computer scientist Alan Turing developed the Church-Turing thesis, which states that natural numbers cannot be computed by a human being unless they are computable by a Turing machine (computer). Due to the fact that computers were not powerful at the time, applications were limited.

August 2022

Keshavarz P, Yazdanpanah F, Emad M, Hajati A, Nejati SF, Ebrahimian Sadabad F, Azrumelashvili T, Mizandari M, Raman SS.

We reviewed the reported imaging findings of myocarditis in the literature following COVID-19 vaccination on cardiac imaging by a literature search in online databases, including Scopus, Medline (PubMed), Web of Science, Embase (Elsevier), and Google Scholar. In total, 532 cases of myocarditis after COVID-19 vaccination were reported (462, 86.8% men and 70, 13.2% women, age range 12 to 80) with the following distribution: Pfizer-BioNTech: 367 (69%), Moderna: 137 (25.8%), AstraZeneca: 12 (2.3%), Janssen/Johnson & Johnson: 6 (1.1%), COVAXIN: 1 (0.1%), and unknown mRNA vaccine: 9 (1.7%). The distribution of patients receiving vaccine dosage was investigated. On cardiac MR Imaging, late intravenous gadolinium enhancement (LGE) was observed mainly in the epicardial/subepicardial segments (90.8%, 318 of 350 enhancing segments), with the dominance of inferolateral segment and inferior walls. Pericardial effusion was reported in 13.1% of cases. The vast majority of patients (94%, 500 of 532) were discharged from the hospital except for 4 (0.7%) cases. Post-COVID-19 myocarditis was most commonly reported in symptomatic men after the second or third dose, with CMRI findings including LGE in 90.8% of inferior and inferolateral epicardial/subepicardial segments. Most cases were self-limited.

August 2022

Wu X, Uhlig J, Blasberg JD, Gettinger SN, Suh RD, Solomon SB, Kim HS.

PURPOSE: To assess the cost effectiveness of microwave ablation (MWA) and stereotactic body radiotherapy (SBRT) for patients with inoperable stage I non-small cell lung cancer (NSCLC). MATERIALS AND METHODS: A literature search was performed in MEDLINE with broad search clusters. A decision-analytic model was constructed over a 5-year period. The model incorporated treatment-related complications and long-term recurrence. All clinical parameters were derived from the literature with preference to long-term prospective trials. A healthcare payers' perspective was adopted. Outcomes were measured in quality-adjusted life years (QALYs) extracted from prior studies and U.S. dollars from Medicare reimbursements and prior studies. Base case calculations, probabilistic sensitivity analysis with 10,000 Monte Carlo simulations, and multiple 1- and 2-way sensitivity analyses were performed.

July 2022

Cai X, Shahandeh N, Ji J, Finn JP, Fishbein GA, Biniwale RM, Ardehali A, Sayah DM, Yang EH.

A 64-year-old man with a history of transcatheter aortic valve replacement (TAVR) and bilateral orthotopic lung transplant was found to have a retrosternal hematoma on annual surveillance chest computed tomography (CT). The patient had a CoreValve Evolut R 34-mm valve (Medtronic, Inc, Minneapolis, MN) implanted for moderate aortic stenosis and severe aortic regurgitation at an outside hospital 2 years before the surveillance CT.

July 2022

Chang R, Patel M.

In pediatric patients, the pelvic and the abdominal contents of hernias of the canal of Nuck have increased risk of strangulation. Early diagnosis of these hernias with ultrasonography is important. We report a case of a hernia of the canal of Nuck presented as a left inguinal mass containing the ipsilateral ovary in a 26-day-old premature infant girl.

July 2022

Lu Z, Lee K, Chen J.

ntertrochanteric fractures occur in the region between the greater and the lesser trochanters along the junction of the femoral neck and the shaft. Isolated greater trochanteric fractures seen on initial radiographs may be shown to have intertrochanteric extension on additional imaging modalities, including magnetic resonanceimaging (MRI), computed tomography, and bone scintigraphy. We report a case of intertrochanteric extension of greater trochanteric fracture in a 59-year-old man who presented with acute worsening of chronic left hip pain after a minor fall. Radiographs ofthe hips revealed a left greater trochanteric fracture with suspected intertrochanteric extension. Computed tomography of the left hip, one day later, showed a minimally displaced fracture of the left greater trochanter without intertrochanteric extension. The same-day MRI of the hip showed an acute nondisplaced intertrochanteric extension of a minimally displaced greater trochanteric fracture. While the greater trochanteric fracture was seen on all three imaging modalities, the intertrochanteric extensionwas distinctly visualized only on MRI.

July 2022

Marathe K, Marasinou C, Li B, Nakhaei N, Li B, Elmore JG, Shapiro L, Hsu W.

BACKGROUND: Amorphous calcifications noted on mammograms (i.e., small and indistinct calcifications that are difficult to characterize) are associated with high diagnostic uncertainty, often leading to biopsies. Yet, only 20% of biopsied amorphous calcifications are cancer. We present a quantitative approach for distinguishing between benign and actionable (high-risk and malignant) amorphous calcifications using a combination of local textures, global spatial relationships, and interpretable handcrafted expert features. METHOD: Our approach was trained and validated on a set of 168 2D full-field digital mammography exams (248 images) from 168 patients. Within these 248 images, we identified 276 image regions with segmented amorphous calcifications and a biopsy-confirmed diagnosis. A set of local (radiomic and region measurements) and global features (distribution and expert-defined) were extracted from each image. Local features were grouped using an unsupervised k-means clustering algorithm. All global features were concatenated with clustered local features and used to train a LightGBM classifier to distinguish benign from actionable cases.

July 2022

Patel PM, Osadchiy V, Quirk M, Dunn MD, Donin NM.

Prostatic artery embolization (PAE) is an effective treatment for men with lower urinary symptoms (LUTS) caused by prostate enlargement, with proven improvement in symptoms and quality of life. Recently, the efficacy of PAE has been successfully demonstrated in massively enlarged glands [1]. It seems, however, that larger glands can present a potential issue due to the presence of a large median lobe, which has been associated with urinary obstruction after PAE [2]. We present the case of an extremely large and adherent devitalized adenomatous mass producing a ball valve effect within the prostatic fossa and causing recurrent urinary retention after PAE.

July 2022

Ruchalski K, Kim HJ, Douek M, Raman S, Patel M, Sai V, Gutierrez A, Levine B, Fischer C, Allen-Auerbach M, Gupta P, Coy H, Villegas B, Brown M, Goldin J.

BACKGROUND: To evaluate the anatomic site(s) of initial disease progression in patients with castration resistant metastatic prostate cancer (mCRPC) in the presence or absence of pre-treatment visceral metastases while on systemic therapy. METHODS: This is a retrospective cohort study of mCRPC patients who have baseline and at least one follow up bone scan and CT chest, abdomen and pelvis (CAP). Disease progression was determined by RECIST and/or ≥ 30% increase in automated bone scan lesion area score. Kaplan-Meier plot was used to estimate the median progression free survival and log-rank tests were used to compare anatomic sites.

July 2022

Vijayasarathi A, Karnezis S, Azizyan A, Salamon N, Sepahdari A.

Primary hyperparathyroidism is a morbid disease that affects multiple organ systems and causes a multitude of debilitating symptoms if not properly diagnosed and treated. Minimally invasive parathyroidectomy is now the standard of care for the treatment of primary hyperparathyroidism. In the hands of experienced high-volume surgeons, the success rate of this treatment is approximately 95%. Preoperative planning with 4-dimensional computed tomography (4DCT) is becoming increasingly common as a first line imaging modality. It is important for general radiologists to become familiar with this type of study in order to better assist their surgical colleagues. This image-rich review will discuss hyperparathyroidism, benefits, and weaknesses of different imaging modalities, 4DCT imaging protocol, relevant anatomy, expected appearance, and location of parathyroid adenomas, ectopic and atypical appearances, multigland disease and important mimics.

July 2022

Wood DE, Kazerooni EA, Aberle D, Berman A, Brown LM, Eapen GA, Ettinger DS, Ferguson JS, Hou L, Kadaria D, Klippenstein D, Kumar R, Lackner RP, Leard LE, Lennes IT, Leung ANC, Mazzone P, Merritt RE, Midthun DE, Onaitis M, Pipavath S, Pratt C, Puri V, Raz D, Reddy C, Reid ME, Sandler KL, Sands J, Schabath MB, Studts JL, Tanoue L, Tong BC, Travis WD, Wei B, Westover K, Yang SC, McCullough B, Hughes M.

The NCCN Guidelines for Lung Cancer Screening recommend criteria for selecting individuals for screening and provide recommendations for evaluation and follow-up of lung nodules found during initial and subsequent screening. These NCCN Guidelines Insights focus on recent updates to the NCCN Guidelines for Lung Cancer Screening.

July 2022

Yoo S, Chen J.

Congenital stenosis of the duodenum secondary to duodenal web is a rare and predominantly pediatric condition due to incomplete recanalization of the duodenal lumen during early gestation. The windsock appearance on a fluoroscopic examination of the upper gastrointestinal tract is pathognomonic for obstructive processes in the duodenum. Here, we report a surgically proven case of duodenal web in an infant.

June 2022

Douek M.

Thermal ablation in the neck has been applied to several clinical conditions, but by far, the most common application is for the treatment of the benign, solid, non-functional thyroid nodule. Though relatively new to the United States, thermal ablation of these nodules has been performed internationally for nearly two decades, especially in South Korea and Italy. A number of ablative techniques - radiofrequency, laser, microwave, high-intensity focused ultrasound, and ethanol - have been studied and reported. This review will focus on the most commonly applied technology for solid non-functional nodules, RFA.

June 2022

Hagiwara A, Oughourlian TC, Cho NS, Schlossman J, Wang C, Yao J, Raymond C, Everson R, Patel K, Mareninov S, Rodriguez FJ, Salamon N, Pope WB, Nghiemphu PL, Liau LM, Prins RM, Cloughesy TF, Ellingson BM.

BACKGROUND: Diffusion MRI estimates of the apparent diffusion coefficient (ADC) have been shown to be useful in predicting treatment response in patients with glioblastoma (GBM), with ADC elevations indicating tumor cell death. We aimed to investigate whether the ADC values measured before and after treatment with immune checkpoint inhibitors (ICIs) and the changes in these ADC values could predict overall survival (OS) in patients with recurrent IDH wild-type GBM. METHODS: Forty-four patients who met the following inclusion criteria were included in this retrospective study: (i) diagnosed with recurrent IDH wild-type GBM and treated with either pembrolizumab or nivolumab and (ii) availability of diffusion data on pre- and post-ICI MRI. Tumor volume and the median relative ADC (rADC) with respect to the normal-appearing white matter within the enhancing tumor were calculated.

June 2022

Kafali SG, Armstrong T, Shih SF, Kim GJ, Holtrop JL, Venick RS, Ghahremani S, Bolster BD Jr, Hillenbrand CM, Calkins KL, Wu HH.

BACKGROUND: Magnetic resonance (MR) elastography of the liver measures hepatic stiffness, which correlates with the histopathological staging of liver fibrosis. Conventional Cartesian gradient-echo (GRE) MR elastography requires breath-holding, which is challenging for children. Non-Cartesian radial free-breathing MR elastography is a potential solution to this problem. OBJECTIVE: To investigate radial free-breathing MR elastography for measuring hepatic stiffness in children. MATHERIALS AND METHODS: In this prospective pilot study, 14 healthy children and 9 children with liver disease were scanned at 3 T using 2-D Cartesian GRE breath-hold MR elastography (22 s/slice) and 2-D radial GRE free-breathing MR elastography (163 s/slice). Each sequence was acquired twice. Agreement in the stiffness measurements was evaluated using Lin's concordance correlation coefficient (CCC) and within-subject mean difference. The repeatability was assessed using the within-subject coefficient of variation and intraclass correlation coefficient (ICC).

June 2022

Moriarty JM, Liao M, Kim GHJ, Yang E, Desai K, Ranade M, Plotnik AN.2022 Feb 17.

BACKGROUND: Right heart thrombi can be a source of considerable morbidity and mortality, especially when associated with pulmonary embolism. METHODS: To understand the safety and procedural efficacy associated with vacuum-assisted thrombectomy using the AngioVac System (AngioDynamics, Latham, NY, USA) to remove right heart thrombi, we conducted a subanalysis of the Registry of AngioVac Procedures in Detail (RAPID) multicenter registry representing 47 (20.1%) of 234 participants in the registry. Forty-two (89.4%) patients had thrombi located in the right atrium alone, three (6.4%) in the right ventricle alone, and two (4.3%) in both the right atrium and ventricle. Four (8.5%) patients had concomitant caval thrombi, three (6.4%) also had catheter-related thrombi, and one (2.1%) patient had both caval and catheter-related thrombi with their right heart thrombi.

June 2022

Ruchalski K, Dewan R, Sai V, McIntosh LJ, Braschi-Amirfarzan M.

Treatment response assessment by imaging plays a vital role in evaluating changes in solid tumors during oncology therapeutic clinical trials. Response Evaluation Criteria in Solid Tumors (RECIST) 1.1 is the reference standard imaging response criteria and provides details regarding image acquisition, image interpretation and categorical response classification. While RECIST 1.1 is applied for the majority of clinical trials in solid tumors, other criteria and modifications have been introduced when RECIST 1.1 outcomes may be incomplete. Available criteria beyond RECIST 1.1 can be explored in an algorithmic fashion dependent on imaging modality, tumor type and method of treatment. Positron Emission Tomography Response Criteria in Solid Tumors (PERCIST) is available for use with PET/CT. Modifications to RECIST 1.1 can be tumor specific, including mRECIST for hepatocellular carcinoma and mesothelioma. Choi criteria for gastrointestinal stromal tumors incorporate tumor density with alterations to categorical response thresholds. Prostate Cancer Working Group 3 (PCWG3) imaging criteria combine RECIST 1.1 findings with those of bone scans. In addition, multiple response criteria have been created to address atypical imaging responses in immunotherapy.

June 2022

Rink JS, Froelich MF, McWilliams JP, Gratzke C, Huber T, Gresser E, Schoenberg SO, Diehl SJ, Nörenberg D.

PURPOSE: The aim of this study was to investigate whether prostatic artery embolization (PAE) can be considered a long-term cost-effective treatment option in patients with lower urinary tract symptoms secondary to benign prostatic hyperplasia in comparison to transurethral resection of the prostate (TURP). METHODS: The in-hospital costs of PAE and TURP in the United States were obtained from a recent cost analysis. Clinical outcomes including nature and rate of adverse events for TURP and PAE along with rates of retreatment because of complications or clinical failure were obtained from peer-reviewed literature. A decision tree-based Markov model was created, analyzing long-term cost-effectiveness for TURP and PAE from a US health care sector perspective. Cost-effectiveness over a time frame of 5 years was estimated while assuming a willingness to pay of $50,000 per quality-adjusted life-year (QALY). The primary outcome was incremental cost-effectiveness ratio.

June 2022

Schroeder G, Edalati M, Tom G, Kuntjoro N, Gutin M, Gurian M, Cuniberto E, Hirth E, Martiri A, Sposato MT, Aminzadeh S, Eichenbaum J, Alizadeh P, Baidya A, Haghniaz R, Nasiri R, Kaneko N, Mansouri A, Khademhosseini A, Sheikhi A.

Metallic coil embolization is a common method for the endovascular treatment of visceral artery aneurysms (VAA) and visceral artery pseudoaneurysms (VAPA); however, this treatment is suboptimal due to the high cost of coils, incomplete volume occlusion, poor reendothelialization, aneurysm puncture, and coil migration. Several alternative treatment strategies are available, including stent flow diverters, glue embolics, gelfoam slurries, and vascular mesh plugs-each of which have their own disadvantages. Here, we investigated the in vitro capability of a shear-thinning biomaterial (STB), a nanocomposite hydrogel composed of gelatin and silicate nanoplatelets, for the minimally-invasive occlusion of simple necked aneurysm models. We demonstrated the injectability of STB through various clinical catheters, engineered an in vitro testing apparatus to independently manipulate aneurysm neck diameter, fluid flow rate, and flow waveform, and tested the stability of STB within the models under various conditions.

June 2022

Sonni I, Felker ER, Lenis AT, Sisk AE, Bahri S, Allen-Auerbach M, Armstrong WR, Suvannarerg V, Tubtawee T, Grogan T, Elashoff D, Eiber M, Raman SS, Czernin J, Reiter RE, Calais J.

The role of prostate-specific membrane antigen (PSMA)-targeted PET in comparison to multiparametric MRI (mpMRI) in the evaluation of intraprostatic cancer foci is not well defined. The aim of our study was to compare the diagnostic performance of ⁶⁸Ga-PSMA-11 PET/CT (PSMA PET/CT), mpMRI, and PSMA PET/CT + mpMRI using 3 independent masked readers for each modality and with histopathology as the gold standard in the detection, intraprostatic localization, and determination of local extension of primary prostate cancer. METHODS: Patients with intermediate- or high-risk prostate cancer who underwent PSMA PET/CT as part of a prospective trial (NCT03368547) and mpMRI before radical prostatectomy were included. Each imaging modality was interpreted by 3 independent readers who were unaware of the other modality result. A central majority rule was applied (2:1). Pathologic examination of whole-mount slices was used as the gold standard. Imaging scans and whole-mount slices were interpreted using the same standardized approach on a segment level and a lesion level. A "neighboring" approach was used to define imaging-pathology correlation for the detection of individual prostate cancer foci. Accuracy in determining the location, extraprostatic extension (EPE), and seminal vesicle invasion (SVI) of prostate cancer foci was assessed using receiver-operating-characteristic curve analysis. Interreader agreement was calculated using intraclass correlation coefficient analysis.

June 2022

Van Dyk K, Wall L, Heimberg BF, Choi J, Raymond C, Wang C, Lai A, Cloughesy TF, Ellingson BM, Nghiemphu P.

AIM: Understanding and supporting quality of life (QoL) and daily functioning in glioma patients is a clinical imperative. In this study, we examined the relationship between cognition, psychological factors, measures of health-related QoL and functioning in glioma survivors. MATERIALS & METHODS: We examined neuropsychological, self-reported cognition, mood and QoL correlates of work and non-work-related daily functioning in 23 glioma survivors, and carried out linear models of the best predictors.

June 2022

Wang C, Cho NS, Dyk KV, Islam S, Raymond C, Choi J, Salamon N, Pope WB, Lai A, Cloughesy TF, Nghiemphu PL, Ellingson BM.

This pilot study investigates structural alterations and their relationships with cognitive function in survivors of diffuse gliomas. Twenty-four survivors of diffuse gliomas (mean age 44.5 ± 11.5), from whom high-resolution T1-weighted images, neuropsychological tests, and self-report questionnaires were obtained, were analyzed. Patients were grouped by degree of cognitive impairment, and interregional correlations of cortical thickness were computed to generate morphometric correlation networks (MCNs).

June 2022

Weigt SS, Kim GJ, Jones HD, Ramsey AL, Amubieya O, Abtin F, Pourzand L, Lee J, Shino MY, DerHovanessian A, Stripp B, Noble PW, Sayah DM, Saggar R, Britton I, Lynch JP 3rd, Belperio JA, Goldin J.

BACKGROUND: Chronic lung allograft dysfunction (CLAD) phenotype determines prognosis and may have therapeutic implications. Despite the clarity achieved by recent consensus statement definitions, their reliance on radiologic interpretation introduces subjectivity. The Center for Computer Vision and Imaging Biomarkers at the University of California, Los Angeles (UCLA) has established protocols for chest high-resolution computed tomography (HRCT)-based computer-aided quantification of both interstitial disease and air-trapping. We applied quantitative image analysis (QIA) at CLAD onset to demonstrate radiographic phenotypes with clinical implications. METHODS: We studied 47 first bilateral lung transplant recipients at UCLA with chest HRCT performed within 90 d of CLAD onset and 47 no-CLAD control HRCTs. QIA determined the proportion of lung volume affected by interstitial disease and air-trapping in total lung capacity and residual volume images, respectively. We compared QIA scores between no-CLAD and CLAD, and between phenotypes. We also assigned radiographic phenotypes based solely on QIA, and compared their survival outcomes.

May 2022

Czap AL, Bahr-Hosseini M, Singh N, Yamal JM, Nour M, Parker S, Kim Y, Restrepo L, Abdelkhaleq R, Salazar-Marioni S, Phan K, Bowry R, Rajan SS, Grotta JC, Saver JL, Giancardo L, Sheth SA.

BACKGROUND: Prehospital automated large vessel occlusion (LVO) detection in Mobile Stroke Units (MSUs) could accelerate identification and treatment of patients with LVO acute ischemic stroke. Here, we evaluate the performance of a machine learning (ML) model on CT angiograms (CTAs) obtained from 2 MSUs to detect LVO. METHODS: Patients evaluated on MSUs in Houston and Los Angeles with out-of-hospital CTAs were identified. Anterior circulation LVO was defined as an occlusion of the intracranial internal carotid artery, middle cerebral artery (M1 or M2), or anterior cerebral artery vessels and determined by an expert human reader. A ML model to detect LVO was trained and tested on independent data sets consisting of in-hospital CTAs and then tested on MSU CTA images. Model performance was determined using area under the receiver-operator curve statistics.

May 2022

Dinh H, Vinuela F, Szeder V, Khatibi K, Mejia LP, Chien A.

A comparative analysis between intravascular guidewire-obtained and computational fluid dynamic (CFD) flow velocity and pressure data using simplified carotid stenosis models was performed. This information was used to evaluate the viability of using guidewire pressure data to provide inlet conditions for CFD flow, and to study the relationship between stenotic length and hemodynamic behavior. Carotid stenosis models differing in diameter and length were prepared and connected to a vascular pulsatile flow simulator. Time-dependent flow velocity and pressure measurements were taken by microcatheter guidewires and compared with CFD data. Guidewire and CFD-generated pressure profiles matched closely in all measurement locations. The guidewire was unable to reliably measure flow velocity at areas associated with higher CFD flow velocities (r = 0.92). CFD results showed that an increased length of stenosis generated expansive regions of elevated wall shear stress (WSS) within and distal to the stenosis. Low WSS was found immediately outside the stenosis outlet. An increase in stenotic length produced higher flow velocities with minimal lengthening of the distal high velocity flow jet due to faster dissipation of translational kinetic energy through turbulence. We found the accuracy of guidewire-obtained velocity measurements is limited to regions unaffected by disturbed flow. WSS and turbulence behavior distal to the stenosis may be important markers to evaluate the severity of atherosclerotic progression as a function of stenotic length.

May 2022

Ellingson BM, Kim GHJ, Brown M, Lee J, Salamon N, Steelman L, Hassan I, Pandya SS, Chun S, Linetsky M, Yoo B, Wen PY, Mellinghoff IK, Goldin J, Cloughesy TF.

BACKGROUND: Since IDH-mutant (mIDH) low-grade gliomas (LGGs) progress slowly and have a relatively long survival, there is a significant need for earlier measurements of clinical benefit. Guidance using the LGG RANO criteria recommends serial bidirectional (2D) measurements on a single slice; however, questions remain as to whether volumetric (3D) measurements are better, since they would allow for more accurate measurements in irregular shaped lesions and allow readers to better assess areas of subtle change. METHODS: Twenty-one (out of 24) non-enhancing, recurrent mIDH1 LGGs were enrolled in a phase I, multicenter, open-label study of oral ivosidenib (NCT02073994), and with imaging pre- and post-treatment as part of this exploratory ad hoc analysis. 2D and 3D measurements on T2-weighted FLAIR images were centrally evaluated at an imaging contract research organization using a paired read and forced adjudication paradigm. The effects of 2D vs 3D measurements on progression-free survival (PFS), growth rate measurement variability, and reader concordance and adjudication rates were quantified.

May 2022

Kao SD, Srinivasa RN, Callese T, Jamshidi N, Plotnik A.

The "gunsight approach" was initially described as the use of overlapping snares and through- and-through puncture of the portal vein and inferior vena cava for the creation of a transcaval portosystemic shunt. This technique can be adapted for the creation of an extra-anatomic chan- nel between any 2 locations where snares can be deployed. We explain the technique, discuss finer technical points, and describe 2 cases where refractory vascular occlusions are crossed using this technique. The first case involves an extensively calcified femoral arterial chronic total occlusion where subintimal tracking past the occlusion is achieved, but luminal re-entry is ham- pered by dense calcific plaque refractory to multiple re-entry devices. The second case involves a chronic venous occlusion along the femoral vein with loss of in-line flow due to prior stenting.

May 2022

Khoo A, Liu LY, Sadun TY, Salmasi A, Pooli A, Felker E, Houlahan KE, Ignatchenko V, Raman SS, Sisk AE Jr, Reiter RE, Boutros PC, Kislinger T.

Multiparametric magnetic resonance imaging (mpMRI) is an emerging standard for diagnosing and prognosing prostate cancer, but ~ 20% of clinically significant tumors are invisible to mpMRI, as defined by the Prostate Imaging Reporting and Data System version 2 (PI-RADSv2) score of one or two. To understand the biological underpinnings of tumor visibility on mpMRI, we examined the proteomes of forty clinically significant tumors (i.e., International Society of Urological Pathology (ISUP) Grade Group 2)-twenty mpMRI-visible and twenty mpMRI-invisible, with matched histologically normal prostate. Normal prostate tissue was indistinguishable between patients with visible and invisible tumors, and invisible tumors closely resembled the normal prostate. These data indicate that mpMRI-visibility arises when tumor evolution leads to large-magnitude proteomic divergences from histologically normal prostate.

May 2022

McWilliams JP, Majumdar S, Kim GH, Lee J, Seals K, Tangchaiburana S, Gilbert S, Duckwiler GR.

BACKGROUND: Hereditary hemorrhagic telangiectasia (HHT) is a vascular bleeding disorder characterized by mucocutaneous telangiectasias and visceral arteriovenous malformations. A frequently debilitating symptom is spontaneous recurrent epistaxis. OBJECTIVE: To evaluate whether doxycycline therapy improves epistaxis in HHT by using a prospective, randomized, placebo-controlled crossover study design. PATIENTS/METHODS: Twenty-two eligible patients between December 2017 and July 2020 at a single center were randomized to one of two study arms: doxycycline treatment followed by placebo, or vice versa. Primary outcomes measured differences in epistaxis severity between treatments. Changes in quality of life, laboratory markers of bleeding, and number of monthly blood transfusions or iron infusions were assessed as secondary endpoints. Additional post hoc endpoints included frequency and duration of dripping epistaxis and gushing epistaxis. A post hoc longitudinal analysis assessed effects of doxycycline over time.

May 2022

McVerry B, Polasko A, Rao E, Haghniaz R, Chen D, He N, Ramos P, Hayashi J, Curson P, Wu CY, Bandaru P, Anderson M, Bui B, Sayegh A, Mahendra S, Carlo DD, Kreydin E, Khademhosseini A, Sheikhi A, Kaner RB.

Unlike growth on tissue, microbes can grow freely on implantable devices with minimal immune system intervention and often form resilient biofilms that continuously pump out pathogenic cells. The efficacy of antibiotics used to treat infection is declining due to increased rates of pathogenic resistance. A simple, one-step zwitterionic surface modification is developed to significantly reduce protein and microbial adhesion to synthetic materials and demonstrate the successful modification of several clinically relevant materials, including recalcitrant materials such as elastomeric polydimethylsiloxane. The treated surfaces exhibit robust adhesion resistance against proteins and microorganisms in both static and flow conditions. Furthermore, the surface treatment prevents the adhesion of mammalian fibroblast cells while displaying no cytotoxicity. To demonstrate the clinical efficacy of the novel technology in the real-world, a surface-treated, commercial silicone foley catheter is developed that is cleared for use by the U.S. Food and Drug Administration (K192034). 16 long-term catheterized patients received surface-treated catheters and completed a Patient Global Impression of Improvement (PGI-I) questionnaire. 10 out of 16 patients described their urinary tract condition post implantation as "much better" or "very much better" and 72% (n = 13) of patients desire to continue using the surface-treated catheter over conventional latex or silicone catheters.

May 2022

Roelofs KA, Duckwiler G, Gundlach B, Yoo B, Diniz SB, Cohen LM, Goldberg RA, Rootman DB.

Accurately characterizing the hemodynamic properties of an orbital vascular malformation (VM) is critical to executing a safe and effective management plan. Dynamic dual-phase Valsalva maneuver-augmented computed tomography angiography (CTA) provides valuable information with respect to the lesion's physio-logic features and often is performed as part of the investigation matrix in cases of orbital VMs.

May 2022

Saber H, Beaman C, Tateshima S.

The use of robot-assisted technology is expanding in interventional laboratories with an increasing number of reports of effective treatment delivery in neurointerventional procedures. Here we report the feasibility of complete robot-assisted neurointervention including the guide catheter and microcatheter manipulations with subsequent embolization of the arterial source of hemorrhage in a patient hospitalized with severe COVID-19 complicated by acute epistaxis.

May 2022

Volkmann ER, Tashkin DP, Roth MD, Goldin J, Kim GHJ.

BACKGROUND: Radiographic end points commonly are included in therapeutic trials for systemic sclerosis (SSc)-interstitial lung disease (ILD); however, the relationship between these outcomes and long-term mortality is unclear. RESEARCH QUESTION: Do short-term changes in radiographic measures of ILD predict long-term survival in patients with SSc? STUDY DESIGN AND METHODS: The Scleroderma Lung Study (SLS) I and II evaluated the safety and efficacy of cyclophosphamide (in SLS I and II) and mycophenolate mofetil (in SLS II) for the treatment of SSc-ILD. Changes in the extent of ILD over time were assessed on high-resolution CT scans of the chest by quantitative image analysis, an approach that applies a computer-based algorithm to assess changes in the radiographic extent of ILD objectively. Participants subsequently were followed for up to 12 years (SLS I) and 8 years (SLS II). Cox proportional hazards models determined whether the change in the quantitative radiographic extent of ILD predicted survival, adjusting for other known predictors of survival.

May 2022

Yao J, Hagiwara A, Oughourlian TC, Wang C, Raymond C, Pope WB, Salamon N, Lai A, Ji M, Nghiemphu PL, Liau LM, Cloughesy TF, Ellingson BM.

Characterization of hypoxia and tissue acidosis could advance the understanding of glioma biology and improve patient management. In this study, we evaluated the ability of a pH- and oxygen-sensitive magnetic resonance imaging (MRI) technique to differentiate glioma genotypes, including isocitrate dehydrogenase (IDH) mutation, 1p/19q co-deletion, and epidermal growth factor receptor (EGFR) amplification, and investigated its prognostic value. A total of 159 adult glioma patients were scanned with pH- and oxygen-sensitive MRI at 3T. We quantified the pH-sensitive measure of magnetization transfer ratio asymmetry (MTR_asym) and oxygen-sensitive measure of R₂^' within the tumor region-of-interest.

April 2022

Chan TL, Choe A.

The term social media refers to a computer-based technology that facilitates the sharing of ideas, thoughts, and information through virtual networks and communities. Social media is internet-based and allows users to engage in quick, electronic communication of material such as personal information, documents, videos, and photos. There are more than 4.5 billion users around the world who access social media via computer, tablet, or smartphone using web-based software or applications. At its inception, social media was used to promote interactions between friends and family, but it has since been widely adopted by businesses, which use it to reach customers. The power of social media lies in its ability to connect and share information with many people simultaneously and its ability to facilitate two-way communication between individuals or groups. Some of the largest social media networks available today include Facebook (FB), Instagram (IG), Twitter, YouTube, and TikTok. By the year 2023, the number of social media users in the United States alone is predicted to be approximately 257 million. According to the Pew Research Center, social media users tend to be younger (18-29 years), better educated, and relatively wealthy.

April 2022

Chen, IE, Ghahremani Koureh S, Loo JT

An aneurysmal bone cyst (ABC) is a rare benign expansile lesion of the bone that consists of hemorrhagic cystic spaces separated by fibrous connective tissue containing osteoid and multinucleated giant cells. The lesion may be primary or secondary. We present a case of ABC in a 7-month-old girl who had a growing, antibiotic-refractory mass in the left chest wall. A computed tomography of the chest confirmed the anatomic location of the mass, but a percutaneous image-guided biopsy and video-assisted thoracoscopic surgery performed during work-up were nondiagnostic. The patient ultimately had a partial rib resection via left thoracotomy. On histologic examination, the...

April 2022

Ding PX, Liu C, Han XW, Lee EW.

A 60-year-old man with a history of congenital intrahepatic portosystemic shunt (CIPS) presented with acute bilateral lower-extremity edema. There were no stigmata of chronic liver disease. However, mildly abnormal liver function tests and ɑ-fetoprotein 79.1 ng/mL were noted. Subsequent imaging revealed a 8 cm right lobe liver mass, extending into the right hepatic vein into the IVC and right atrium (A,B). An 8 mm side-to-side intrahepatic shunt between the right portal vein and the IVC (C,D — CT; E – US) was confirmed. A transfemoral biopsy of the IVC lesion demonstrated a poorly differentiated HCC (F). A CIPS is rare. The overall incidence is 1:30,000 births and 1:50,000 for those beyond early life. Because of a reduced portal flow and compensatorily increased hepatic arterial flow in CIPS, benign nodular liver lesions are common. However, HCC is very rare. In fact, IVC and right atrial tumor thrombi arising from HCC due to CIPS are extremely rare and result a poor prognosis (median survival of 1-4 months).

April 2022

Hao F, Eghbalieh N, So A, Lee EW.

Seven patients underwent microwave ablation of hepatic tumors; during ablation, a hepatic nerve plexus block was used for pain control. The mean visual analog scale (VAS) score for pain (scale, 0-10) was 0.3 ± 0.5 (SD) at baseline and 2.5 ± 1.4, 2.6 ± 1.4, and 2.3 ± 0.9 at 1, 5, and 10 minutes during ablation. Two patients reported a VAS score of 4 or greater during ablation, which improved in both patients to a VAS score of 3 after one rescue sedation dose. The remaining patients required no additional sedation. No major complication occurred. No patient required conversion to general anesthesia.

April 2022

Khatibi K, Saber H, Javahery R, Kaneko N, Ponce Mejia LL, Tateshima S.

A teenager with a history of acute myeloid leukemia presented with headache, nausea and blurry vision over a 2 week period. The MRI of the brain was concerning for the presence of a myeloid sarcoma within the right sigmoid sinus. For evaluation of venous obstruction and the underlying lesion the patient underwent a cerebral angiogram and transvenous biopsy of the sigmoid sinus lesion using a stent retriever and aspiration catheter. The tissue extracted was consistent with myeloid sarcoma. This pathologic finding was consistent with the recurrence of leukemia and guided the targeted oncologic treatment.

April 2022

Kinnaird A, Yerram NK, O'Connor L, Brisbane W, Sharma V, Chuang R, Jayadevan R, Ahdoot M, Daneshvar M, Priester A, Delfin M, Tran E, Barsa DE, Sisk A, Reiter RE, Felker E, Raman S, Kwan L, Choyke PL, Merino MJ, Wood BJ, Turkbey B, Pinto PA, Marks LS.

PURPOSE: The underlying premise of prostate cancer active surveillance (AS) is that cancers likely to metastasize will be recognized and eliminated before cancer-related disease can ensue. Our study was designed to determine the prostate cancer upgrading rate when biopsy guided by magnetic resonance imaging (MRGBx) is used before entry and during AS. MATERIALS AND METHODS: The cohort included 519 men with low- or intermediate-risk prostate cancer who enrolled in prospective studies (NCT00949819 and NCT00102544) between February 2008 and February 2020. Subjects were preliminarily diagnosed with Gleason Grade Group (GG) 1 cancer; AS began when subsequent MRGBx confirmed GG1 or GG2. Participants underwent confirmatory MRGBx (targeted and systematic) followed by surveillance MRGBx approximately every 12 to 24 months. The primary outcome was tumor upgrading to ≥GG3.

April 2022

Kinzel AJ, Chen J.

A 1-day-old girl, late preterm (36 weeks 3 days) infant, was admitted to the neonatal intensive care unit for respiratory distress and megacystis seen on a prenatal ultrasound at 24 weeks of gestation. A babygram (anteroposterior view of the entire body) showed absence of bowel gas, and abdominal ultrasound revealed grade 4 bilateral hydronephrosis. The patient was subsequently diagnosed with megacystis-microcolon-intestinal hypoperistalsis syndrome and was taken to the operating room for appropriate treatment.

April 2022

Loo JT, Zhou BL.

Almost all cases of isolated levocardia or situs inversus with levocardia are associated with congenital heart disease. We report a case of situs inversus with levocardia, double-outlet right ventricle, atrioventricular discordance, pulmonary atresia, patent ductus arteriosus, atrial septal defect, and ventricular septal defect in a neonate. An overview of anatomy and relevant definitions with radiographic correlation will be presented along with a synopsis of current medical literature...

March 2022

Dumont RA, Palma Diaz MF, Hsu W, Sepahdari AR.

The purpose of the current study was to assess the prevalence of cyst formation at the brain-tumor interface in olfactory neuroblastoma. We used the UCLA patient-based Pathology and Radiology Head and Neck Database (UPP&R HAND) to identify the largest patient cohort reported to date with imaging and pathology data. Eighteen of thirty-one patients (58.1%) had evidence of intracranial extension on MRI, while four (22.0%) demonstrated cyst formation at the brain-tumor interface. The extent of intracranial extension was by far the strongest predictor for intracranial cyst formation, regardless of Hyams tumor grade, using a binary logistics regression model (p = 0.002) and ROC curve analysis (AUC 94.6%). Cyst formation at the brain-tumor interface was an uncommon imaging finding, and tends to occur with a larger component of intracranial tumor extension.

March 2022

François CJ, Hecht EM, Roditi G, Finn JP.

This review guides readers through the selection and setup of standardized noncardiac chest MRA protocols, including contrast-enhanced MRA (CE-MRA) and noncontrast MRA (NC-MRA), sequences that can be used in a variety of clinical situations. After reviewing basic principles described in the first three tutorials in this series on CE-MRA and NC-MRA, this online presentation details the use of MRA in specific clinical scenarios: thoracic aortic aneurysm, aortic dissection, congenital heart disease, vasculitis, central veins, and pulmonary embolus. Tips and tricks for optimization of the sequences, image acquisition, and image interpretation are provided. This module is the fourth in a series created on behalf of the Society for Magnetic Resonance Angiography (SMRA), a group of researchers and clinicians who are passionate about the benefits of MRA but understand its challenges.

March 2022

Goldman J, Hagiwara A, Yao J, Raymond C, Ong C, Bakhti R, Kwon E, Farhat M, Torres C, Erickson LG, Curl BJ, Lee M, Pope WB, Salamon N, Nghiemphu PL, Ji M, Eldred BS, Liau LM, Lai A, Cloughesy TF, Chung C, Ellingson BM.

BACKGROUND & PURPOSE: While relative cerebral blood volume (rCBV) may be diagnostic and prognostic for survival in glioblastoma (GBM), changes in rCBV during chemoradiation in the subset of newly diagnosed GBM with subtotal resection and the impact of MGMT promoter methylation status on survival have not been explored. This study aimed to investigate the association between rCBV response, MGMT methylation status, and progression-free (PFS) and overall survival (OS) in newly diagnosed GBM with measurable enhancing lesions. METHODS: 1,153 newly diagnosed IDH wild-type GBM patients were screened and 53 patients (4.6%) had measurable post-surgical tumor (>1mL). rCBV was measured before and after patients underwent chemoradiation. Patients with a decrease in rCBV >10% were considered rCBV Responders, while patients with an increase or a decrease in rCBV <10% were considered rCBV Non-Responders. The association between change in enhancing tumor volume, change in rCBV, MGMT promotor methylation status, and PFS or OS were explored.

March 2022

Keshavarz P, Raman SS.

PURPOSE: This systematic review and meta-analysis compares the efficacy of three combination therapies, including transarterial chemoembolization (TACE) with radiofrequency ablation (RFA), microwave ablation (MWA), and cryoablation (CRA) for the treatment of patients with hepatocellular carcinoma (HCC). METHODS: Online databases, including Scopus, Web of Science, PubMed, Embase, CNKI, Google Scholar, and Cochrane Library were searched.

March 2022

Kinnaird A, Brisbane W, Kwan L, Priester A, Chuang R, Barsa DE, Delfin M, Sisk A, Margolis D, Felker E, Hu J, Marks LS.

INTRODUCTION: A functional tool to optimize patient selection for magnetic resonance imaging (MRI)-guided prostate biopsy (MRGB) is an unmet clinical need. We sought to develop a prostate cancer risk calculator (PCRC-MRI) that combines MRI and clinical characteristics to aid decision-making for MRGB in North American men. METHODS: Two prospective registries containing 2354 consecutive men undergoing MRGB (September 2009 to April 2019) were analyzed. Patients were randomized into five groups, with one group randomly assigned to be the validation cohort against the other four groups as the discovery cohort. The primary outcome was detection of clinically significant prostate cancer (csPCa) defined as Gleason grade group ≥2. Variables included age, ethnicity, digital rectal exam (DRE), prior biopsy, prostate-specific antigen (PSA), prostate volume, PSA density, and MRI score. Odds ratios (OR) were calculated from multivariate logistic regression comparing two models: one with clinical variables only (clinical) against a second combining clinical variables with MRI data (clinical+MRI).

March 2022

Shahrouki P, Khan SN, Yoshida T, Iskander PJ, Ghahremani S, Finn JP.

BACKGROUND: Gadofosveset is a gadolinium-based blood pool contrast agent that was approved by the United States Food and Drug Administration in 2008. Its unanticipated withdrawal from production in 2016 created a void in the blood pool agent inventory and highlighted the need for an alternative agent with comparable imaging properties. OBJECTIVE: The purpose of our study is to compare the diagnostic image quality, vascular contrast-to-noise ratio (CNR) and temporal signal characteristics of gadofosveset trisodium and ferumoxytol at similar molar doses for high-resolution, three-dimensional (3-D) magnetic resonance (MR) venography in children. MATERIALS & METHODS: The medical records and imaging data sets of patients who underwent high-resolution 3-D gadofosveset-enhanced MR venography (GE-MRV) or ferumoxytol-enhanced MR venography (FE-MRV) were retrospectively reviewed. Two groups of 20 pediatric patients (age- and weight-matched with one patient common to both groups; age range: 2 days-15 years) who underwent high-resolution 3-D GE-MRV or FE-MRV at similar molar doses were identified and analyzed. Qualitative analysis of image quality and vessel definition was performed by two blinded pediatric radiologists. Interobserver agreement was assessed with the AC1 (first-order agreement coefficient) statistic. Signal-to-noise ratio (SNR) and CNR of the inferior vena cava and aorta were measured in the steady-state venous phase. Medical records were retrospectively reviewed for any adverse reactions associated with either contrast agent.

March 2022

Zhang Y, Lu Q, Monsoor T, Hussain SA, Qiao JX, Salamon N, Fallah A, Sim MS, Asano E, Sankar R, Staba RJ, Engel J Jr, Speier W, Roychowdhury V, Nariai H.

Intracranially recorded interictal high-frequency oscillations have been proposed as a promising spatial biomarker of the epileptogenic zone. However, its visual verification is time-consuming and exhibits poor inter-rater reliability. Furthermore, no method is currently available to distinguish high-frequency oscillations generated from the epileptogenic zone (epileptogenic high-frequency oscillations) from those generated from other areas (non-epileptogenic high-frequency oscillations). To address these issues, we constructed a deep learning-based algorithm using chronic intracranial EEG data via subdural grids from 19 children with medication-resistant neocortical epilepsy to: (i) replicate human expert annotation of artefacts and high-frequency oscillations with or without spikes, and (ii) discover epileptogenic high-frequency oscillations by designing a novel weakly supervised model. The 'purification power' of deep learning is then used to automatically relabel the high-frequency oscillations to distill epileptogenic high-frequency oscillations. Using 12 958 annotated high-frequency oscillation events from 19 patients, the model achieved 96.3% accuracy on artefact detection (F1 score = 96.8%) and 86.5% accuracy on classifying high-frequency oscillations with or without spikes (F1 score = 80.8%) using patient-wise cross-validation.

February 2022

Canon CL, Chick JFB, DeQuesada I, Gunderman RB, Hoven N, Prosper AE.

Physician burnout is increasingly recognized as a public health crisis given the impact of burnout on physicians, their families, patients, communities, and population health. The COVID-19 pandemic has superimposed a new set of challenges for physicians to navigate, including unique challenges presented to radiologists. Radiologists from a diversity of backgrounds, practice settings, and career stages were asked for their perspectives on burnout.

February 2022

Chan TL, De R, Reno E.

Aspiring physicians typically know less about radiology compared to other specialties and are often unaware of how medical imaging is interpreted or what a radiologist does. Prior studies have focused on improving radiology education in medical school, as it is taught by non radiologists at many institutions (1) or as a senior elective, when students have already decided on their specialty. A study by Fielding et al demonstrated that only 15% of medical students participating in a third or fourth year radiology clinical clerkship planned on going into radiology.

February 2022

Chan TL, Fischer CP.A

A 55-year-old woman was called back from screening mammography because of left axillary lymphadenopathy (Fig. 1A). She had received the second dose of Pfizer COVID-19 vaccine in the left deltoid 2 weeks before the screening examination. Targeted ultrasound showed reactive axillary lymph nodes and a separate round mass inferomedial to the humeral head (Fig. 1B). Subsequent shoulder MRI showed an inferior lobulated paralabral cyst (Fig. 1C) that accounted for the mammographic finding. Recent COVID-19 vacci-nation poses a diagnostic dilemma for women undergoing screening mammography. Unilateral axillary lymphadenopathy in this setting is often reactive, but the imaging findings are nonspecific. The Society of Breast Imaging [1] recommends short-term sonographic follow-up to document improvement. In rare instances, paralabral cysts may resemble reactive axillary lymph nodes [2]. Paralabral cysts are associated with labral tears and can cause pain, weakness, and denervation of the supraspinatus and infraspinatus muscles secondary to nerve compression. These are benign and do not require intervention or imaging follow-up.

February 2022

Chong J, Guorgui J, Coy H, Ito T, Lu M, DiNorcia J, Agopian VG, Farmer DG, Raman SS, Busuttil RW, Kaldas FM.

BACKGROUND: Frailty has been implicated as a negative predictor of Liver Transplant (LT) outcomes. However, an understanding of changes in patient muscle mass peri-LT, and their effect in high-acuity patients remains lacking. We examined the impact of perioperative muscle mass changes (ΔSMI) on high-acuity (MELD ≥35) LT recipients. MATERIALS AND METHODS: Skeletal muscle index (SMI) was calculated using CT imaging. Patients were divided into two groups, based on severity of peri-operative SMI decrease. LT recipients with chronic end-stage liver disease, MELD ≥35, and abdominal CT ≤ 30 days prior, and 30-90 days post LT were included. [1011 adult LT recipients reviewed, 2012-2018].

February 2022

Hayase J, Chin R, Cao M, Hu P, Shivkumar K, Bradfield JS.

Stereotactic body radiation therapy (SBRT) is a promising new method for non-invasive management of life-threatening ventricular arrhythmias. Numerous case reports and case series have provided encouraging short-term results suggesting good efficacy and safety, but randomized data and long-term outcomes are not yet available. The primary hypothesis as to the mechanism of action for SBRT relates to the development of cardiac fibrosis in arrhythmogenic myocardial substrate; however, limited animal model data offer conflicting insights into this theory. The use of SBRT for patients with refractory ventricular arrhythmias is rapidly increasing, but ongoing translational science work and randomized clinical trials will be critical to address many outstanding questions regarding this novel therapy.

February 2022

Hayase J, Chin R, Kwon M, Cao M, Hu P, Ajijola O, Boyle N, Shivkumar K, Bradfield JS.

Catheter ablation remains the principal intervention to target scar-based, macroreentrant ventricular arrhythmias. However, the use of stereotactic body radiation therapy (SBRT) for recurrent ventricular arrhythmias is becoming increasingly common, with initial case reports and case series describing promising early results, particularly in patients who are poor candidates for, or have failed, catheter ablation procedures. Nonetheless, many questions remain as to the mechanism of action, safety, and long-term efficacy. In this report, we expand upon a case that has been briefly described previously that provides important insights into the limitations of SBRT in a patient who required open chest surgical ablation after failing SBRT.

February 2022

Huang RY, Pope WB.

This article reviews recent advances in the use of standard and advanced imaging techniques for diagnosis and treatment of central nervous system (CNS) tumors, including glioma and brain metastasis. Following the recent transition from a histology-based approach in classifying CNS tumors to one that integrates histology with the molecular information of tumor, the approaches for imaging CNS tumors have also been adapted to this new framework. Some challenges related to the diagnosis and treatment of CNS tumors, such as differentiating tumor from treatment-related imaging changes, require further progress to implement advanced imaging for clinical use.

February 2022

Kwon JH, Kim MD, Kim SH, Lee EW, Kahlid SA.

INTRODUCTION: Irreversible electroporation (IRE) is a novel technique that uses a non-thermal ablation to avoid adjacent major structure injury. The aim of this study was to sequentially evaluate the effects of IRE on the femoral nerve during acute-to-delayed periods in a rabbit model. MATERIAL AND METHODS: Ultrasound-guided IRE of femoral neurovascular bundles was performed in seven rabbits. Functional and histopathologic evaluation was performed sequentially after IRE. The extent of nerve fiber affected, and the proportion of perineurial inflammation and surrounding tissue injury were recorded.

February 2022

Shahrouki P, Lee EW, Ruehm S.

Deep venous thrombosis is a hitherto under-recognized complication occurring in patients with polysplenia syndrome, despite the high prevalence of venous anomalies such as interrupted inferior vena cava (IVC) with azygos/hemiazygos continuation. Here we report the first case of concurrent polysplenia (as evidenced by interrupted IVC with azygos/hemiazygos continuation, multiple left-sided spleens, bowel malrotation with inverted mesenteric veins, preduodenal portal vein, and pancreatic hypoplasia/partial agenesis of the dorsal pancreas) and sickle cell trait, complicated by extensive deep venous thrombosis refractory to medical and interventional radiologic management.

February 2022

Sonnenblick EB, Lebron-Zapata L, Yang R, Dodelzon K, Sevilimedu V, Milch H, Dialani V, Dontchos BN, Destounis S, Grimm L.

PURPOSE: The aim of this study was to investigate breast radiologists' practices related to recording sex and gender in the electronic medical record, knowledge and attitudes about breast cancer screening recommendations for transgender individuals, and experience and willingness to enter screening mammography data from transgender patients into databases that document service provision and outcomes of cancer detection protocols. METHODS: A 19-question anonymous survey was distributed by e-mail to all active physician members of the Society of Breast Imaging. Response characteristics were assessed as frequencies and percentages and compared between groups using the Fisher exact test or 𝛘² test. The degree of agreement between questions was assessed using the McNemar test.

February 2022

Tsai YC, Tseng HS, Lee EW, Lee RC, Chiu NC, Hwang HE, Liu CA.

BACKGROUND: To evaluate the techniques, efficacy, and safety for treating vascularly inaccessible abdominal visceral pseudoaneurysms by direct puncture and embolization. METHODS: A retrospective study of 5 consecutive patients who underwent percutaneous direct puncture embolization for intra-abdominal pseudoaneurysms in our institution between January 2009 and December 2016. Technical aspects, success, clinical outcome, and complications were discussed.

February 2022

Wang C, Van Dyk K, Cho N, Raymond C, Choi J, Salamon N, Pope WB, Lai A, Cloughesy TF, Nghiemphu PL, Ellingson BM.

As treatments for diffuse gliomas have advanced, survival for patients with gliomas has also increased. However, there remains limited knowledge on the relationships between brain connectivity and the lasting changes to cognitive function that glioma survivors often experience long after completing treatment. This resting-state functional magnetic resonance imaging (rs-fMRI) study explored functional connectivity (FC) alterations associated with cognitive function in survivors of gliomas. In this pilot study, 22 patients (mean age 43.8 ± 11.9) with diffuse gliomas who completed treatment within the past 10 years were evaluated using rs-fMRI and neuropsychological measures. Novel rs-fMRI analysis methods were used to account for missing brain in the resection cavity. FC relationships were assessed between cognitively impaired and non-impaired glioma patients, along with self-reported cognitive impairment, non-work daily functioning, and time with surgery. In the cognitively non-impaired patients, FC was stronger in the medial prefrontal cortex, rostral prefrontal cortex, and intraparietal sulcus compared to the impaired survivors. When examining non-work daily functioning, a positive correlation with FC was observed between the accumbens and the intracalcarine cortices, while a negative correlation with FC was observed between the parietal operculum cortex and the cerebellum. Additionally, worse self-reported cognitive impairment and worse non-work daily functioning were associated with increased FC between regions involved in cognition and sensorimotor processing. These preliminary findings suggest that neural correlates for cognitive and daily functioning in glioma patients can be revealed using rs-fMRI. Resting-state network alterations may serve as a biomarker for patients' cognition and functioning.

February 2022

Wichova H, Peng K, Ledbetter L, Slattery W, Brackmann D, Lekovic G.

OBJECTIVE: To evaluate the safety of 3 Tesla (T) magnetic resonance imaging (MRI) in patients with auditory brainstem implants (ABI) with the magnet removed at implantation and report incidence of complications. STUDY DESIGN: Retrospective chart review. SETTING: Tertiary neurotology ambulatory practice. PATIENTS: Patients with diagnosis of Neurofibromatosis, type 2 (NF2) with functional ABIs.

February 2022

Woodard S, Zamora K, Allen E, Choe AI, Chan TL, Li Y, Khorjekar GR, Tirada N, Destounis S, Weidenhaft MC, Hartsough R, Park JM.

PURPOSE: To assess the percentage of papillomas from all biopsies performed, comparing differences in patient age and race at a single institution. To assess trends in biopsied papillomas at institutions throughout the United States (US). METHODS: This is a HIPPA-compliant IRB-approved single-institution (Southern1) retrospective review to assess race and age of all-modality-biopsied non-malignant papillomas as a percentage of all biopsies (percentage papillomas calculated as papilloma biopsies/all biopsies) from January 2012 to December 2019. To assess national variation, several academic or large referral centers were contacted to provide data regarding papilloma percentages, biopsy modalities, and trends in case numbers. Trends were estimated using the method of analysis of variance (ANOVA). Comparisons of differences in trends were assessed.

January 2022

Armstrong T, Zhong X, Shih SF, Felker E, Lu DS, Dale BM, Wu HH.

PURPOSE: To investigate the agreement, intra-session repeatability, and inter-reader agreement of liver proton-density fat fraction (PDFF) and R₂* quantification using free-breathing 3D stack-of-radial MRI, with and without self-gated motion compensation, compared to reference breath-hold techniques in subjects with fatty liver disease (FLD). METHODS: In this institutional review board-approved prospective study, thirty-eight adults with FLD and/or iron overload (24 male, 58 ± 12 years) were imaged at 3T using free-breathing stack-of-radial MRI, breath-hold 3D Cartesian MRI, and breath-hold single-voxel MR spectroscopy (SVS). Each sequence was acquired twice in random order. To assess agreement compared to reference breath-hold techniques, the dependency of liver PDFF and/or R₂* quantification on the sequence, radial sampling factor, and radial self-gating temporal resolution was assessed by calculating the Bayesian mean difference (MDB) of the posteriors. Intra-session repeatability and inter-reader agreement (two independent readers) were assessed by the coefficient of repeatability (CR) and intraclass correlation coefficient (ICC), respectively.

January 2022

Cusumano LR, Mathevosian S, Sayre JW, McWilliams JP

BACKGROUND: Prostatic artery embolization (PAE) is an emerging treatment for benign prostatic hyperplasia (BPH). However, changes in public interest in PAE over time, especially relative to interest in alternative BPH treatments, are difficult to assess. The online tool for analysis of the popularity of top search queries (Google Trends; Alphabet Inc) provides a relative search volume (RSV) of specified keywords and insight about patterns of user searches. PURPOSE: The purpose of this study is to assess changes in public interest in PAE over time and compare them with changes in public interest in alternative BPH treatments as indicated by search queries. MATERIAL AND METHODS: Using Google Trends, we identified the RSV of specified keywords within search queries submitted between 2010 and 2019 in the United States. The RSVs of keywords with high search volume were identified and normalized on a scale of values from 0 to 100. Interest in PAE was assessed by comparing RSVs and trends of the keyword PAE as well as of other prostate-treatment-related keywords. Prostate embolization was a PAE-related, BPH-treatment-specific keyword with the highest average RSV. A linear regression analysis was performed to characterize annual search trends of the use of these keywords. Subsequently, the annual search trend of prostate embolization was compared with that of keywords related to transurethral resection of the prostate (TURP) and minimally invasive surgical treatments (MISTs).

January 2022

Enzmann D.

The future of IR will evolve as a result of current trends in advances in medicine, disease biology, technology, and IR devices and accoutrements. Changes in the trends that lie at the center of the differentiation of IR from other treatment specialties will have the greatest impact. Differentiation revolves around image guidance knowledge and procedural treatment skills and involves three key components: access, mapping, and action, all of which have the common thread of imaging knowledge. The main trends that are discussed are: image-guided diagnostics (IgDx), image-guided treatment (IgRx), sub-specialization in IgRx, large device design for IgRx, multimodality IgRx, interdisciplinary IgRx, and decentralized IgRx growth. Success in attaining a patient-facing "front-line" patient position will determine the future not only of IR but of radiology as a field. IgRx is anti-commoditization immunization...

January 2022

Fried I, Fahoum F, Frew A, Andelman F, Andelman-Gur MM, Salamon N.

Fourteen-year-old girl (AB) with no previous medical illness began to notice brief but distinct episodes of guilt and distress, occasionally followed by urinary incontinence. In the beginning, the patient attributed these feelings to recent or ongoing events such as "fighting with friends" or "doing something wrong at school". With time, she became increasingly baffled by these episodes, trying to "figure out if the situation was causing guilt" (Supplamentary Table 1). These episodes were noted by the patient to be more frequent in social-affective situations, such as standing in front of large groups or arguing with her parents. For nearly a year the patient kept these episodes to herself until she had a generalized tonic clonic seizure, leading to neurological consultation and epilepsy diagnosis. Although the patient was treated with multiple anti-seizure medications, the episodes did not abate.

January 2022

Gallegos A, Gordon LK, Moreno G, Nahm S, Brown K, Walker V, Rangel V, Clavijo S, Casillas A.

State-of-the-art diagnosis of radiculopathy relies on "highly subjective" radiologist interpretation of magnetic resonance imaging of the lower back. Currently, the treatment of lumbar radiculopathy and associated lower back pain lacks coherence due to an absence of reliable, objective diagnostic biomarkers. Using emerging machine learning techniques, the subjectivity of interpretation may be replaced by the objectivity of automated analysis. However, training computer vision methods requires a curated database of imaging data containing anatomical delineations vetted by a team of human experts. In this chapter, we outline our efforts to develop such a database of curated imaging data alongside the required delineations. We detail the processes involved in data acquisition and subsequent annotation. Then we explain how the resulting database can be utilized to develop a machine learning-based objective imaging biomarker. Finally, we present an explanation of how we validate our machine learning-based anatomy delineation algorithms. Ultimately, we hope to allow validated machine learning models to be used to generate objective biomarkers from imaging data-for clinical use to diagnose lumbar radiculopathy and guide associated treatment plans.

January 2022

Gaonkar B, Cook K, Yoo B, Salehi B, Macyszyn L.

State-of-the-art diagnosis of radiculopathy relies on "highly subjective" radiologist interpretation of magnetic resonance imaging of the lower back. Currently, the treatment of lumbar radiculopathy and associated lower back pain lacks coherence due to an absence of reliable, objective diagnostic biomarkers. Using emerging machine learning techniques, the subjectivity of interpretation may be replaced by the objectivity of automated analysis. However, training computer vision methods requires a curated database of imaging data containing anatomical delineations vetted by a team of human experts. In this chapter, we outline our efforts to develop such a database of curated imaging data alongside the required delineations. We detail the processes involved in data acquisition and subsequent annotation. Then we explain how the resulting database can be utilized to develop a machine learning-based objective imaging biomarker. Finally, we present an explanation of how we validate our machine learning-based anatomy delineation algorithms. Ultimately, we hope to allow validated machine learning models to be used to generate objective biomarkers from imaging data-for clinical use to diagnose lumbar radiculopathy and guide associated treatment plans.

January 2022

Ghosh S, Azzi J, Chan AM, Nael K, Renteria AS, Steinberg A, Petersen BE.

Neurolymphomatosis (NL) is a rare condition caused by the lymphomatous or leukemic infiltration of nerves and manifests as neuropathy. Most often, NL is associated with B-lineage non-Hodgkin lymphoma (NHL) and only infrequently occurs in conjunction with T- or NK-lineage NHL. Extranodal NK/T-cell lymphoma (ENKTL)-associated NL is exceedingly unusual, with only 9 cases described in the English language literature, in addition to our case. Diagnosis of NL is challenging, as the entity can mimic neuropathies of more common etiologies, and an adequate biopsy may be difficult to obtain. Timely diagnosis demands a high index of suspicion, especially for patients without a history of hematologic malignancy. We expand upon a unique case of NL exclusively involving cranial nerves and cauda equina nerve roots, as the initial manifestation of ENKTL, and contextualize our findings within the framework of previously reported NK/T-lineage NL cases.

January 2022

Hagiwara A, Tatekawa H, Yao J, Raymond C, Everson R, Patel K, Mareninov S, Yong WH, Salamon N, Pope WB, Nghiemphu PL, Liau LM, Cloughesy TF, Ellingson BM.

This study aimed to differentiate isocitrate dehydrogenase (IDH) mutation status with the voxel-wise clustering method of multiparametric magnetic resonance imaging (MRI) and to discover biological underpinnings of the clusters. A total of 69 patients with treatment-naïve diffuse glioma were scanned with pH-sensitive amine chemical exchange saturation transfer MRI, diffusion-weighted imaging, fluid-attenuated inversion recovery, and contrast-enhanced T1-weighted imaging at 3 T. An unsupervised two-level clustering approach was used for feature extraction from acquired images. The logarithmic ratio of the labels in each class within tumor regions was applied to a support vector machine to differentiate IDH status. The highest performance to predict IDH mutation status was found for 10-class clustering, with a mean area under the curve, accuracy, sensitivity, and specificity of 0.94, 0.91, 0.90, and 0.91, respectively. Targeted biopsies revealed that the tissues with labels 7-10 showed high expression levels of hypoxia-inducible factor 1-alpha, glucose transporter 3, and hexokinase 2, which are typical of IDH wild-type glioma, whereas those with labels 1 showed low expression of these proteins. In conclusion, A machine learning model successfully predicted the IDH mutation status of gliomas, and the resulting clusters properly reflected the metabolic status of the tumors.

January 2022

Hu A, Seals K, Thomas M, Hathout G

Coronavirus Disease 2019 (COVID-19) has had an enormous impact on both the medical community as well as society as a whole. Research on the pathogenesis and the treatment of the disease is rapidly emerging, with new observations and hypotheses appearing daily. One aspect that has been receiving increasing attention is the occurrence of both arterial and venous thrombotic complications in patients with COVID-19. We report three cases of thromboembolic complications in patients affected by COVID-19 and discuss clinical features, pathophysiology, and the proposed approaches to management of vascular complications in these patients. Through our discussion, we also urge physicians to be vigilant for any symptoms or signs suggestive of thrombosis in patients with COVID-19.

January 2022

Ito T, Guorgui J, Markovic D, Coy H, Younan SM, DiNorcia J 3rd, Agopian VG, Farmer DG, Raman SS, Busuttil RW, Kaldas FM.

BACKGROUND: Sarcopenia has gained momentum as a potential risk-stratification tool in liver transplantation (LT). While LT recipients recently have more advanced end-stage liver disease, the impact of sarcopenia in high acuity recipients with a high model for end-stage liver disease (MELD) score remains unclear. METHODS: We retrospectively assessed sarcopenia by calculating skeletal muscle index (SMI) from cross-sectional area at third lumbar vertebra (cm²) and height (m²) in 296 patients with a CT ≤ 30 days prior to LT. Sex-specific SMI cut-offs were developed, and its impact was assessed in patients with MELD ≥ 35.

January 2022

Lauria M, Singhrao K, Stiehl B, Low D, Goldin J, Barjaktarevic I, Santhanam A.

PURPOSE: Computational fluid dynamics (CFD) of lung airflow during normal and pathophysiological breathing provides insight into regional pulmonary ventilation. By integrating CFD methods with 4D lung imaging workflows, regions of normal pulmonary function can be spared during treatment planning. To facilitate the use of CFD simulations in a clinical setup, a robust, automated, and CFD-compliant airway mesh generation technique is necessary. METHODS: We define a CFD-compliant airway mesh to be devoid of blockages of airflow and leaks in the airway path, both of which are caused by airway meshing errors that occur when using conventional meshing techniques. We present an algorithm to create a CFD-compliant airway mesh in an automated manner. Beginning with a medial skeleton of the airway segmentation, the branches were tracked, and 3D points at which bifurcations occur were identified. Airway branches and bifurcation features were isolated to allow for automated and careful meshing that considered their anatomical nature.

January 2022

Li W, Li J, Polson J, Wang Z, Speier W, Arnold C.

Semantic segmentation of histopathology images can be a vital aspect of computer-aided diagnosis, and deep learning models have been effectively applied to this task with varying levels of success. However, their impact has been limited due to the small size of fully annotated datasets. Data augmentation is one avenue to address this limitation. Generative Adversarial Networks (GANs) have shown promise in this respect, but previous work has focused mostly on classification tasks applied to MR and CT images, both of which have lower resolution and scale than histopathology images. There is limited research that applies GANs as a data augmentation approach for large-scale image semantic segmentation, which requires high-quality image-mask pairs. In this work, we propose a multi-scale conditional GAN for high-resolution, large-scale histopathology image generation and segmentation. Our model consists of a pyramid of GAN structures, each responsible for generating and segmenting images at a different scale. Using semantic masks, the generative component of our model is able to synthesize histopathology images that are visually realistic. We demonstrate that these synthesized images along with their masks can be used to boost segmentation performance, especially in the semi-supervised scenario.

January 2022

Lin Y, Fu M, Ding R, Inoue K, Jeon CY, Hsu W, Aberle DR, Prosper AE.

Lung cancer screening (LCS) is effective in reducing mortality, particularly when patients adhere to follow-up recommendations standardized by the Lung CT Screening Reporting & Data System (Lung-RADS). Nevertheless, patient adherence to recommended intervals varies, potentially diminishing benefit from screening. We conducted a systematic review and meta-analysis of patient adherence to Lung-RADS-recommended screening intervals. We systematically searched MEDLINE, EMBASE, Web of Science, the Cochrane Central Register of Controlled Trials, and major radiology and oncology conference archives between April 28, 2014, and December 17, 2020. Eligible studies mentioned patient adherence to the recommendations of Lung-RADS. The review protocol was registered with PROSPERO (CRD42020189326). We identified 24 eligible studies for qualitative summary, of which 21 were suitable for meta-analysis.

January 2022

Moran J, Lookstein RA, Ranade M.

Several treatment options exist for acute intra-abdominal arterial thromboembolic events, including systemic thrombolytics, endovascular therapy, and less commonly surgery. A novel alternative treatment intervention for acute intra-abdominal arterial thrombus is the use of stent retriever (SR) devices, tools traditionally applied for treatment of acute vascular thrombosis in stroke patients. This brief report presents two cases of acute intra-abdominal arterial thrombosis successfully managed by deployment of SRs. Furthermore, it details the history, device mechanism, and design of SRs and describes cases in literature involving effective extracranial SR application.

January 2022

Nobori A, Jumniensuk C, Chen X, Enzmann D, Dry S, Nelson S, Arnold CW.

PURPOSE: Multidisciplinary oncology meetings, or tumor boards (TBs), ensure and facilitate communication between specialties regarding the management of cancer cases to improve patient care. The organization of TB and the preparation and presentation of patient cases are typically inefficient processes that require the exchange of patient information via e-mail, the hunting for data and images in the electronic health record, and the copying and pasting of patient data into desktop presentation software. METHODS: We implemented a standards-based electronic health record-integrated application that automated several aspects of TB organization and preparation. We hypothesized that this application would increase the efficiency of TB preparation, reduce errors in patient entry, and enhance communication with the clinical team. Our experimental design used a prospective evaluation by pathologists who were timed in preparing for weekly TBs using both the new application and the conventional method. In addition, patient data entry errors associated with each method were tracked, and TB attendees completed a survey evaluating satisfaction with the new application.

January 2022

Shahrouki P, Felker ER, Raman SS, Jeong WK, Lu DS, Finn JP.

INTRODUCTION: The off-label use of ferumoxytol as a vascular MR imaging agent is growing rapidly. However, the properties of ferumoxytol suggest that it may play an important role in the detection and characterization of abdominal mass lesions. METHODS: Thirty-six patients with benign abdominal mass lesions who underwent MR angiography with ferumoxytol also had T2-weighted HASTE imaging and fat-suppressed 3D T1-weighted imaging. The T1 and T2 enhancement characteristics of the lesions were analyzed and correlated with other imaging modalities and/or surgical findings and/or clinical follow-up.

January 2022

Singh AS, Hecht JR, Rosen L, Wainberg ZA, Wang X, Douek M, Hagopian A, Andes R, Sauer L, Brackert SR, Chow W, DeMatteo R, Eilber FC, Glaspy JA, Chmielowski B.

PURPOSE: Most gastrointestinal stromal tumors (GIST) are driven by KIT/PDGFRa mutations. Tyrosine kinase inhibitor benefit is progressively less after imatinib failure. This phase II trial analyzed the efficacy of nivolumab (N) or nivolumab + ipilimumab (N + I) in patients with refractory GIST. PATIENTS AND METHODS: Patients with advanced/metastatic GIST refractory to at least imatinib were randomized 1:1 in a noncomparative, parallel group, unblinded phase II trial of N (240 mg every 2 weeks) or N + I (240 mg every 2 weeks + 1 mg/kg every 6 weeks). The primary endpoint was the objective response rate of N alone or N+I by RECIST 1.1 in the intent-to-treat population.

January 2022

Yu T, Yang EH, Ranade M.

In the U.S., pulmonary embolism (PE) is a common cause of cardiovascular death. Right heart thrombus (RHT) occurs in approximately 4% of patients with PE, and when concurrent is associated with increased 30-day PE-related and all-cause mortality. The consensus on optimal management of acute massive or high-risk PE is unclear, and even less so for concurrent RHT. In this report, we review a successful multidisciplinary coordination of vacuum-assisted thrombectomy (VAT) of a complex pacemaker lead-associated RHT in a patient with concurrent acute PE and significant comorbidities, using the AngioVac system (Vortex Medical, Norwell, MA). VAT is a reasonable treatment option that should be considered particularly for patients who are poor surgical or thrombolytic candidates. Procedural success and patient outcomes can be further optimized through multidisciplinary collaboration such as with the Pulmonary Embolism Response Team (PERT) model.

January 2022

Thomas M, Abtin F, Roth A, Yim C, Pahwa A, Paige J, Ukpo O.

Coronavirus disease 2019 (COVID-19) caused by SARS-CoV-2 produced a global pandemic with significant mortality. As autopsies are not routinely performed on all decedents with SARS-CoV-2 infection, postmortem CT (PMCT) may be valuable to provide additional information on the cause of death and risk factors known to be associated with an increased mortality in COVID-19. The purpose of this manuscript is to review the PMCT findings in a series of 42 decedents with SARS-CoV-2 infection from our institution. Retrospective analysis of 42 decedents who had a positive postmortem nasopharyngeal swab for SARS-CoV-2 and had a PMCT were included in this study. Images were reviewed for pulmonary findings seen in COVID-19 and other organ involvement.

January 2022

Zhong X, Armstrong T, Gao C, Nickel MD, Han F, Dale BM, Li X, Kafali SG, Hu P, Wu HH, Deshpande V.

PURPOSE: To develop an accelerated k-space shift calibration method for free-breathing 3D stack-of-radial MRI quantification of liver proton-density fat fraction (PDFF) and R₂^* METHODS: Accelerated k-space shift calibration was developed to partially skip acquisition of k-space shift data in the through-plane direction then interpolate in processing, as well as to reduce the in-plane averages. A multi-echo stack-of-radial sequence with the baseline calibration was evaluated on a phantom versus vendor-provided reference-standard PDFF and R₂^* values at 1.5T, and in 13 healthy subjects and 5 clinical subjects at 3T with respect to reference-standard breath-hold Cartesian acquisitions. PDFF and R₂^* maps were calculated with different calibration acceleration factors offline and compared to reference-standard values using Bland-Altman analysis. Bias and uncertainty were evaluated using normal distribution and Bayesian probability of difference (P < .05 considered significant).