June 2021Physical Examination and Ultrasound Evaluation of Patients with Superficial Venous Disease.
Casadaban LC, Moriarty JM, Hoffman CH.
Systematic and standardized evaluation of superficial venous disease, guided by knowledge of the various clinical presentations, venous anatomy, and pathophysiology of reflux, is essential for appropriate diagnosis and optimal treatment. Duplex ultrasonography is the standard for delineating venous anatomy, detecting anatomic variants, and identifying the origin of venous insufficiency. This article reviews tools and techniques essential for physical examination and ultrasound assessment of patients with superficial venous disease.
June 2021Estimation of Fractional Myocardial Blood Volume and Water Exchange Using Ferumoxytol-enhanced Magnetic Resonance Imaging.
Colbert CM, Thomas MA, Yan R, Radjenovic A, Finn JP, Hu P, Nguyen KL.
Fractional myocardial blood volume (fMBV) estimated using ferumoxytol-enhanced magnetic resonance imaging (MRI) (FE-MRI) has the potential to capture a hemodynamic response to myocardial hypoperfusion during contrast steady state without reliance on gadolinium chelates. Ferumoxytol has a long intravascular half-life and its use for steady-state MRI is off-label. The aim of this prospective study was to optimize and evaluate a two-compartment model for estimation of fMBV based on FE-MRI. Nine healthy swine and one swine with artificially induced single-vessel coronary stenosis underwent MRI on a 3.0 T clinical magnet. Myocardial longitudinal spin-lattice relaxation rate (R1) was measured using the 5(3)3(3)3 modified Look-Locker inversion recovery (MOLLI) sequence before and at contrast steady state following seven ferumoxytol infusions (0.125-4.0 mg/kg). fMBV and water exchange were estimated using a two-compartment model. Model-fitted fMBV was compared to simple fast-exchange fMBV approximation and percent change in pre- and postferumoxytol R1. Dose undersampling schemes were investigated to reduce acquisition duration. Variation in fMBV was assessed using one-way analysis of variance. Fast-exchange fMBV and ferumoxytol dose undersampling were evaluated using Bland-Altman analysis. Healthy normal swine showed a mean mid-ventricular fMBV of 7.2 ± 1.4% and water exchange rate of 11.3 ± 5.1 s-1 . There was intersubject variation in fMBV (p < 0.05) without segmental variation (p = 0.387). fMBV derived from eight-dose and four-dose sampling schemes had no significant bias (mean difference = 0.07, p = 0.541, limits of agreement -1.04% [-1.45, -0.62%] to 1.18% [0.77, 1.59%]). Pixel-wise fMBV in one swine model with coronary artery stenosis showed elevated fMBV in ischemic segments (apical anterior: 11.90 ± 4.00%, apical septum: 16.10 ± 5.71%) relative to remote segments (apical inferior: 9.59 ± 3.35%, apical lateral: 9.38 ± 2.35%). A two-compartment model based on FE-MRI using the MOLLI sequence may enable estimation of fMBV in studies of ischemic heart disease. LEVEL OF EVIDENCE: 2. TECHNICAL EFFICACY STAGE: 2.
June 2021Cell-free DNA Methylation and Transcriptomic Signature Prediction of Pregnancies with Adverse Outcomes.
Del Vecchio G, Li Q, Li W, Thamotharan S, Tosevska A, Morselli M, Sung K, Janzen C, Zhou X, Pellegrini M, Devaskar SU.
Although analysis of maternal plasma cell-free content has been employed for screening of genetic abnormalities within a pregnancy, limited attention has been paid to its use for the detection of adverse pregnancy outcomes (APOs) based on placental function. Here we investigated cell-free DNA and RNA content of 102 maternal and 25 cord plasma samples. Employing a novel deconvolution methodology, we found that during the first trimester, placenta-specific DNA increased prior to the subsequent development of gestational diabetes with no change in patients with preeclampsia while decreasing with maternal obesity. Moreover, using cell-free RNA sequencing, APOs revealed 71 differentially expressed genes early in pregnancy. We noticed the upregulation of S100A8, MS4A3, and MMP8 that have been already associated with APOs but also the upregulation of BCL2L15 and the downregulation of ALPL that have never been associated with APOs. We constructed a classifier with a positive predictive ability (AUC) of 0.91 for APOs, 0.86 for preeclampsia alone and 0.64 for GDM. We conclude that placenta-specific cell-free nucleic acids during early gestation provide the possibility of predicting APOs prior to the emergence of characteristic clinical features.
June 2021Giant Mediastinal Lymphocele after Esophagectomy Successfully Treated with Thoracic Duct Embolization.
Ding PX, Liu C, Lu HB, Wang L, Li ZM, Lee EW.
A 64-year old man had developed a giant mediastinal lymphocele after undergoing esophagectomy for the treatment of esophageal squamous cell carcinoma. The thoracic duct was embolized with six micro-coils, followed by embolization using a 1:3 mixture of N-butyl-2-cyanoacrylate (Histoacryl; B. Braun, Melsungen, Germany) and ethiodized oil. Resolution of the lymphocele was achieved within 5 days after embolization. To the best of our knowledge, ours is the first reported case of thoracic duct embolization for the treatment of mediastinal lymphocele.
June 2021Relative Oxygen Extraction Fraction (rOEF) MR Imaging Reveals Higher Hypoxia in Human Epidermal Growth Factor Receptor (EGFR) Amplified Compared with Non-amplified Gliomas.
Oughourlian TC, Yao J, Hagiwara A, Nathanson DA, Raymond C, Pope WB, Salamon N, Lai A, Ji M, Nghiemphu PL, Liau LM, Cloughesy TF, Ellingson BM.
PURPOSE: Epidermal growth factor receptor (EGFR) amplification promotes gliomagenesis and is linked to lack of oxygen within the tumor microenvironment. Using hypoxia-sensitive spin-and-gradient echo echo-planar imaging and perfusion MRI, we investigated the influence of EGFR amplification on tissue oxygen availability and utilization in human gliomas. METHODS: This study included 72 histologically confirmed EGFR-amplified and non-amplified glioma patients. Reversible transverse relaxation rate (R2'), relative cerebral blood volume (rCBV), and relative oxygen extraction fraction (rOEF) were calculated for the contrast-enhancing and non-enhancing tumor regions. Using Student t test or Wilcoxon rank-sum test, median R2', rCBV, and rOEF were compared between EGFR-amplified and non-amplified gliomas. ROC analysis was performed to assess the ability of imaging characteristics to discriminate EGFR amplification status. Overall survival (OS) was determined using univariate and multivariate cox models. Kaplan-Meier survival curves were plotted and compared using the log-rank test.
June 2021Novel Dual-Lumen Drainage Catheter to Enhance the Active Evacuation of Complex Fluid Collections.
Roberts DG, Goudie MJ, Kim AJ, Kim H, Khademhosseini A, McWilliams JP.
PURPOSE: To compare the performance of a dual-lumen flushable drainage catheter to a conventional catheter for complex fluid collection drainage. METHODS: Two prototype catheters (20- and 28-F) were created by incorporating a customized infusion lumen within the wall of a large-bore conventional drainage catheter, which facilitated simultaneous irrigation of the drainage lumen and the targeted collection via inward- and outward-facing infusion side holes. These were tested against unaltered 20- and 28-F conventional catheters to determine if the injection of a dedicated flush lumen improved rapidity and completeness of gravity drainage. In vitro models were created to simulate serous fluid, purulent/exudative fluid, particulate debris, and acute hematoma.
June 2021Caterpillar Mechanical Embolization Device: A New Vascular Plug.
Sweigert J, Lee EW.
Vascular plugs are a popular and effective mechanical embolization device with several distinct advantages over other embolic devices including their superior control in high-flow vessels, precise deployability, and reduced procedure time because of their ability to achieve rapid occlusion.
June 2021Outcomes with Multi-disciplinary Management of Central Lung Tumors with CT-guided Percutaneous High Dose Rate Brachyablation.
Yoon SM, Suh R, Abtin F, Moghanaki D, Genshaft S, Kamrava M, Drakaki A, Liu S, Venkat P, Lee A, Chang AJ.
BACKGROUND: Centrally located lung tumors present treatment challenges given their proximity to mediastinal structures including the central airway, esophagus, major vessels, and heart. Therapeutic options can be limited for medically inoperable patients, particularly if they have received previous thoracic radiotherapy. High dose rate (HDR) brachyablation was developed to improve the therapeutic ratio for patients with central lung tumors. The purpose of this study is to report initial safety and efficacy outcomes with this treatment for central lung malignancies. METHODS: From September 2015 to August 2019, a total of 25 patients with 37 pulmonary tumors were treated with percutaneous HDR brachyablation. Treatment was delivered by a multi-disciplinary team of interventional radiologists, pulmonologists, and radiation oncologists. Twenty-three patients received a median dose of 21.5 Gy (range 15-27.5) in a single fraction, whereas two patients received median dose of 24.75 Gy (range 24-25.5) over 2-3 fractions. Tumor local control (LC) was evaluated by Response Evaluation Criteria in Solid Tumors v1.1. Treatment-related toxicities were graded by Common Terminology Criteria for Adverse Events v5.0, with adverse events less than 90 days defined as acute, and those occurring later were defined as late. LC, progression-free survival (PFS), and overall survival (OS) rates were estimated by the Kaplan-Meier method.
May 2021Hepatobiliary Cancers, Version 2.2021, NCCN Clinical Practice Guidelines in Oncology.
Benson AB, D'Angelica MI, Abbott DE, Anaya DA, Anders R, Are C, Bachini M, Borad M, Brown D, Burgoyne A, Chahal P, Chang DT, Cloyd J, Covey AM, Glazer ES, Goyal L, Hawkins WG, Iyer R, Jacob R, Kelley RK, Kim R, Levine M, Palta M, Park JO, Raman S, Reddy S, Sahai V, Schefter T, Singh G, Stein S, Vauthey JN, Venook AP, Yopp A, McMillian NR, Hochstetler C, Darlow SD.
The NCCN Guidelines for Hepatobiliary Cancers focus on the screening, diagnosis, staging, treatment, and management of hepatocellular carcinoma (HCC), gallbladder cancer, and cancer of the bile ducts (intrahepatic and extrahepatic cholangiocarcinoma). Due to the multiple modalities that can be used to treat the disease and the complications that can arise from comorbid liver dysfunction, a multidisciplinary evaluation is essential for determining an optimal treatment strategy. A multidisciplinary team should include hepatologists, diagnostic radiologists, interventional radiologists, surgeons, medical oncologists, and pathologists with hepatobiliary cancer expertise. In addition to surgery, transplant, and intra-arterial therapies, there have been great advances in the systemic treatment of HCC. Until recently, sorafenib was the only systemic therapy option for patients with advanced HCC. In 2020, the combination of atezolizumab and bevacizumab became the first regimen to show superior survival to sorafenib, gaining it FDA approval as a new frontline standard regimen for unresectable or metastatic HCC. This article discusses the NCCN Guidelines recommendations for HCC.
May 2021ACR Appropriateness Criteria® Syncope.
Expert Panels on Cardiac Imaging and Neurological Imaging, Kligerman SJ, Bykowski J, Hurwitz Koweek LM, Policeni B, Ghoshhajra BB, Brown MD, Davis AM, Dibble EH, Johnson TV, Khosa F, Ledbetter LN, Leung SW, Liebeskind DS, Litmanovich D, Maroules CD, Pannell JS, Powers WJ, Villines TC, Wang LL, Wann S, Corey AS, Abbara S
Syncope and presyncope lead to well over one million emergency room visits in the United States each year. Elucidating the cause of syncope or presyncope, which are grouped together given similar etiologies and outcomes, can be exceedingly difficult given the diverse etiologies. This becomes more challenging as some causes, such as vasovagal syncope, are relatively innocuous while others, such as cardiac-related syncope, carry a significant increased risk of death. While the mainstay of syncope and presyncope assessment is a detailed history and physical examination, imaging can play a role in certain situations. In patients where a cardiovascular etiology is suspected based on the appropriate history, physical examination, and ECG findings, resting transthoracic echocardiography is usually considered appropriate for the initial imaging. While no imaging studies are considered usually appropriate when there is a low probability of cardiac or neurologic pathology, chest radiography may be appropriate in certain clinical situations. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.
May 2021ACR Appropriateness Criteria® Head Trauma: 2021 Update.
Expert Panel on Neurological Imaging, Shih RY, Burns J, Ajam AA, Broder JS, Chakraborty S, Kendi AT, Lacy ME, Ledbetter LN, Lee RK, Liebeskind DS, Pollock JM, Prall JA, Ptak T, Raksin PB, Shaines MD, Tsiouris AJ, Utukuri PS, Wang LL, Corey AS.
Head trauma (ie, head injury) is a significant public health concern and is a leading cause of morbidity and mortality in children and young adults. Neuroimaging plays an important role in the management of head and brain injury, which can be separated into acute (0-7 days), subacute (<3 months), then chronic (>3 months) phases. Over 75% of acute head trauma is classified as mild, of which over 75% have a normal Glasgow Coma Scale score of 15, therefore clinical practice guidelines universally recommend selective CT scanning in this patient population, which is often based on clinical decision rules. While CT is considered the first-line imaging modality for suspected intracranial injury, MRI is useful when there are persistent neurologic deficits that remain unexplained after CT, especially in the subacute or chronic phase. Regardless of time frame, head trauma with suspected vascular injury or suspected cerebrospinal fluid leak should also be evaluated with CT angiography or thin-section CT imaging of the skull base, respectively. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.
May 2021Accuracy and Safety of 1,055 Transjugular Liver Biopsies in Postliver Transplant Patients.
Lee EW, Sue MJ, Saab S, DiNorcia J 3rd, McWilliams JP, Kaldas F, Ding PX, Padia SA, Agopian V, Farmer D, Busuttil RW.
INTRODUCTION: The purpose of this study was to investigate the rates of complications and diagnostic yield of transjugular liver biopsy (TJLB) in deceased donor liver transplant (DDLT) recipients. METHODS: From January 2009 to December 2019, 1,055 TJLBs were performed in 603 adult DDLT recipients with a mean age of 54 (±12 years). Data were retrospectively reviewed to determine the diagnostic efficacy and incidence of major and minor complications in the 3-day and 1-month period after TJLB. In addition, data were stratified according to platelet count and international normalized ratio to determine the safety of TJLB in patients with varying degrees of coagulopathy.
May 2021Preservation of Posterior Tibial Artery Flow Following Dissection With Associated Aneurysmal Degeneration in Ehlers-Danlos Syndrome Type IV Treated With Flow-Diverting Stent.
Plotnik AN, Srinivasa RN, Szeder V, Moriarty J.
Ehlers-Danlos syndrome type IV (EDS-IV), the vascular type, is a rare genetic disorder affects the large and medium size arteries resulting in dissections, often with aneurysmal degeneration, intramural hematomas and pseudoaneurysms. Embolization or ligation is standard management for aneurysm formation. We present a case of an EDS-IV patient with a posterior tibial artery dissection with associated aneurysm successfully treated with Flow Diversion stent (FDS) preserving vessel patency and excluding the aneurysm. FDS technology allows for low profile, micro-catheter deliverable treatment options to exclude aneurysms in EDS-IV patients that are may be prone to spasm and dissection using more conventional stent graft technology.
May 2021A Primer on RECIST 1.1 for Oncologic Imaging in Clinical Drug Trials.
Ruchalski K, Braschi-Amirfarzan M, Douek M, Sai V, Gutierrez A, Dewan R, Goldin J.
Drug discovery and approval in oncology is mediated by the use of imaging to evaluate drug efficacy in clinical trials. Imaging is performed while patients receive therapy to evaluate their response to treatment. Response criteria, specifically Response Evaluation Criteria in Solid Tumors version 1.1 (RECIST 1.1), are standardized and can be used at different time points to classify response into the categories of complete response, partial response, stable disease, or disease progression. At the trial level, categorical responses for all patients are summated into image-based trial endpoints. These outcome measures, including objective response rate (ORR) and progression-free survival (PFS), are characteristics that can be derived from imaging and can be used as surrogates for overall survival (OS). Similar to OS, ORR and PFS describe the efficacy of a drug. U.S. Food and Drug Administration (FDA) regulatory approval requires therapies to demonstrate direct evidence of clinical benefit, such as improved OS. However, multiple programs have been created to expedite drug approval for life-threatening illnesses, including advanced cancer. ORR and PFS have been accepted by the FDA as adequate predictors of OS on which to base drug approval decisions, thus substantially shortening the time and cost of drug development (1). Use of imaging surrogate markers for drug approval has become increasingly common, accounting for more than 90% of approvals through the Accelerated Approval Program and allowing for use of many therapies which have altered the course of cancer.
May 2021Preferential Tumor Localization in Relation to 18F-FDOPA Uptake for Lower-grade Gliomas.
Tatekawa H, Uetani H, Hagiwara A, Yao J, Oughourlian TC, Ueda I, Raymond C, Lai A, Cloughesy TF, Nghiemphu PL, Liau LM, Bahri S, Pope WB, Salamon N, Ellingson BM.
PURPOSE: Although tumor localization and 3,4-dihydroxy-6-18F-fluoro-L-phenylalanine (FDOPA) uptake may have an association, preferential tumor localization in relation to FDOPA uptake is yet to be investigated in lower-grade gliomas (LGGs). This study aimed to identify differences in the frequency of tumor localization between FDOPA hypometabolic and hypermetabolic LGGs using a probabilistic radiographic atlas. METHODS: Fifty-one patients with newly diagnosed LGG (WHO grade II, 29; III, 22; isocitrate dehydrogenase wild-type, 21; mutant 1p19q non-codeleted,16; mutant codeleted, 14) who underwent FDOPA positron emission tomography (PET) were retrospectively selected. Semiautomated tumor segmentation on FLAIR was performed. Patients with LGGs were separated into two groups (FDOPA hypometabolic and hypermetabolic LGGs) according to the normalized maximum standardized uptake value of FDOPA PET (a threshold of the uptake in the striatum) within the segmented regions. Spatial normalization procedures to build a 3D MRI-based atlas using each segmented region were validated by an analysis of differential involvement statistical mapping.
May 2021Cortical Morphometric Correlational Networks Associated with Cognitive Deficits in First Episode Schizophrenia.
Wang C, Oughourlian T, Tishler TA, Anwar F, Raymond C, Pham AD, Perschon A, Villablanca JP, Ventura J, Subotnik KL, Nuechterlein KH, Ellingson BM.
Schizophrenia (SCZ) is a chronic cognitive and behavioral disorder associated with abnormal cortical activity during information processing. Several brain structures associated with the seven performance domains evaluated using the MATRICS (Measurement and Treatment Research to Improve Cognition in Schizophrenia) Consensus Cognitive Battery (MCCB) have shown cortical volume loss in first episode schizophrenia (FES) patients. However, the relationship between morphological organization and MCCB performance remains unclear. Therefore, in the current observational study, high-resolution structural MRI scans were collected from 50 FES patients, and the morphometric correlation network (MCN) using cortical volume was established to characterize the cortical pattern associated with poorer MCCB performance. We also investigated topological properties, such as the modularity, the degree and the betweenness centrality. Our findings show structural volume was directly and strongly associated with the cognitive deficits of FES patients in the precuneus, anterior cingulate, and fusiform gyrus, as well as the prefrontal, parietal, and sensorimotor cortices. The medial orbitofrontal, fusiform, and superior frontal gyri were not only identified as the predominant nodes with high degree and betweenness centrality in the MCN, but they were also found to be critical in performance in several of the MCCB domains. Together, these results suggest a widespread cortical network is altered in FES patients and that performance on the MCCB domains is associated with the core pathophysiology of SCZ.
May 2021Image-Guided Percutaneous Thermal Ablation of Oligometastatic Ovarian and Non-Ovarian Gynecologic Tumors.
Yuan F, Wei SH, Konecny GE, Memarzadeh S, Suh RD, Sayre J, Lu DS, Raman SS.
PURPOSE: To assess the safety, feasibility, and efficacy of percutaneous thermal ablation (TA) in the treatment of metastatic gynecologic (GYN) tumors. MATERIALS AND METHODS: A study cohort of 42 consecutive women (mean age, 59. years; range, 25-78 years) with metastatic GYN tumors (119 metastatic tumors) treated with radiofrequency (n = 47 tumors), microwave (n = 47 tumors), or cryogenic (n = 30 tumors) ablation from over 2,800 ablations performed from January 2001 to January 2019 was identified. The primary GYN neoplasms consisted of ovarian (27 patients; 77 tumors; mean tumor diameter [MTD], 2.50 cm), uterine (7 patients; 26 tumors; MTD, 1.89 cm), endometrial (5 patients; 10 tumors; MTD, 2.8 cm), vaginal (2 patients; 5 tumors; MTD, 2.40 cm), and cervical (1 patient; 1 tumor; MTD, 1.90 cm) cancers. In order of descending frequency, metastatic tumors treated by TA were located in the liver or liver capsule (74%), lungs (13%), and peritoneal implants (9%). Single tumors were also treated in the kidneys, rectus muscle, perirectal soft tissue (2.5%), and retroperitoneal lymph nodes (1.6%). All efficacy parameters of TA and definitions of major and minor adverse events are categorized by the latest Society of Interventional Radiology reporting standards.
April 2021Pelvic Floor Ultrasound: When, Why, and How?
Bahrami S, Khatri G, Sheridan AD, Palmer SL, Lockhart ME, Arif-Tiwari H, Glanc P.
Pelvic floor disorders are a significant medical issue, reportedly affecting nearly one in four women in the United States. Nonetheless, until the last decade, there has been relatively limited imaging research into this highly prevalent disorder. The three major imaging modalities utilized to assess pelvic floor function are ultrasound, MRI and fluoroscopy. Pelvic floor ultrasound is a rapidly emerging technique which takes advantage of the widespread availability of ultrasound, the non-invasive and relatively inexpensive approach and the incorporation of real-time imaging and software advances which permit 3-D volume imaging. Pelvic floor ultrasound provides the opportunity to optimize patient counseling and enhance pre-operative planning by providing an anatomic and functional roadmap for the referring clinician. We recommend the consideration of pelvic floor ultrasound, as described here, as an addition to the imaging armamentarium available to physicians and surgeons serving this patient population.
April 2021CT Evaluation of Unrepaired/incidental Congenital Cardiovascular Diseases in Adults.
Bedayat A, Jalili MH, Hassani C, Chalian H, Reuhm S, Moriarty J.
Congenital heart disease (CHD) affects approximately one million people in the USA with the number increasing by 5% each year. Patients are usually both diagnosed and treated in infancy, however many of them may have subclinical CHD that remains undiagnosed until late adulthood. Patients with complex CHD tend to be symptomatic and are diagnosed at a younger age than those with a single defect. CHDs can be divided into three categories, including cardiac, great vessels and coronary artery anomalies. Recent advances in computed tomography (CT) technology with faster acquisition time and improved spatial resolution allow for detailed evaluation of cardiac morphology and function. The concomitant increased utilization of CT has simultaneously led to more sensitive detection and more thorough diagnosis of CHD. Recognition of and understanding the imaging attributes specific to each anomaly is important for radiologists in order to make a correct and definite diagnosis. This article reviews the spectrum of CHDs, which persist into adulthood that may be encountered by radiologists on CT.
April 2021Female Lower Urinary Tract Symptom Prevention and Treatment Strategies on Social Media: Mixed Correlation With Evidence.
Burton CS, Gonzalez G, Vaculik K, Khalil C, Zektser Y, Arnold C, Almario CV, Spiegel BMR, Anger JT.
OBJECTIVE: To evaluate the level of evidence behind recommendations on social media for disease prevention in five lower urinary tract symptoms. MATERIALS & METHODS: We conducted a digital analysis of anonymous online posts on social media sites collected by a social media data mining service. One thousand posts about pelvic organ prolapse, stress urinary incontinence, overactive bladder, urinary tract infection, and interstitial cystitis/bladder pain syndrome were randomly selected. We analyzed these posts for recommendations regarding the prevention and treatment of these diseases, which were then compared to recommendations in available clinical guidelines and assessed for level of evidence.
April 2021Minimizing Echo and Repetition Times in Magnetic Resonance Imaging Using a Double Half-echo k-space Acquisition and Low-rank Reconstruction.
Bydder M, Ali F, Ghodrati V, Hu P, Yao J, Ellingson BM.
Sampling k-space asymmetrically (ie, partial Fourier sampling) in the readout direction is a common way to reduce the echo time (TE) during magnetic resonance image acquisitions. This technique requires overlap around the center of k-space to provide a calibration region for reconstruction, which limits the minimum fractional echo to ∿60% before artifacts are observed. The present study describes a method for reconstructing images from exact half echoes using two separate acquisitions with reversed readout polarity, effectively providing a full line of k-space without additional data around central k-space. This approach can benefit sequences or applications that prioritize short TE, short inter-echo spacing or short repetition time. An example of the latter is demonstrated to reduce banding artifacts in balanced steady-state free precession.
April 2021Gut Wrenching: Cases of Missed Gastrointestinal Tumors and Their Mimics on Computed Tomography.
Capiro N, Flink C, Sai V, Beckett K.
Computed tomography (CT) of the abdomen and pelvis is one of the most common imaging studies ordered through the emergency department (ED). Because these studies are ordered for the detection of acute abnormalities and due to the relatively low incidence in patients presenting through the ED, gastrointestinal tumors are commonly missed. Moreover, many CT findings of malignant tumors overlap with benign entities, which can present a diagnostic challenge. This review article will describe the common CT findings of gastric, small bowel, colon, and appendiceal cancer as well as some of the common benign gastrointestinal conditions with similar imaging findings.
April 2021The Emerging Role of Quantification of Imaging for Assessing the Severity and Disease Activity of Emphysema, Airway Disease, and Interstitial Lung Disease.
There has been an explosion of use for quantitative image analysis in the setting of lung disease due to advances in acquisition protocols and postprocessing technology, including machine and deep learning. Despite the plethora of published papers, it is important to understand which approach has clinical validation and can be used in clinical practice. This paper provides an introduction to quantitative image analysis techniques being used in the investigation of lung disease and focusses on the techniques that have a reasonable clinical validation for being used in clinical trials and patient care.
April 2021Guidelines for the Evaluation of Pulmonary Nodules Detected Incidentally or by Screening: A Survey of Radiologist Awareness, Agreement, and Adherence From the Watch the Spot Trial.
Gould MK, Altman DE, Creekmur B, Qi L, de Bie E, Golden S, Kaplan CP, Kelly K, Miglioretti DL, Mularski RA, Musigdilok VV, Smith-Bindman R, Steltz JP, Wiener RS, Aberle DR, Dyer DS, Vachani A.
PURPOSE: The aim of this study was to examine radiologists' beliefs about existing guidelines for pulmonary nodule evaluation. METHODS: A self-administered survey was developed to ascertain awareness of, agreement with, and adherence to published guidelines, including those from the Fleischner Society and the Lung CT Screening Reporting and Data System (Lung-RADS™). Surveys were distributed to 514 radiologists at 13 health care systems that are participating in a large, pragmatic trial of pulmonary nodule evaluation. Prespecified comparisons were made among groups defined by type of health system, years of experience, reader volume, and study arm.
April 2021Percutaneous Intrauterine Device Placement: A Solution for Hematometra Due to Cervicovaginal Agenesis.
Kallini JR, Grisales T, Foote D, Quirk M, Hoffman C.
Möllerian duct underdevelopment results in agenesis and atresia of the vagina,cervix, or uterus, which can lead to hematometra and hematometrocolpos.Management includes vaginal-cervical serial dilation and/or surgery andmenstrual suppression with endovaginallevonorgestrel intrauterine device(IUD) placement. However, these options are not feasible in vaginal agenesisbecause there is no external tract. This report describes the percutaneousplacement of an IUD to treat hematometra due to cervicovaginal agenesis.
April 2021Trans-Synaptic Degeneration of the Optic Radiation from Optic Nerve Atrophy.
Kihira S, Arnold AC, Pawha PS, Villablanca P, Nael K.
Fourty-seven-year-old woman with 5-year history of progressive decreased left eye vision. Optical coherence tomography showed optic nerve atrophy (left > right) and brain MRI revealed T2 hyperintense signal along the course of left optic radiations. We present a case of a trans-synaptic degeneration of the optic radiation in a patient with confirmed optic atrophy. Trans-synaptic degeneration of the optic radiation without associated infarct or inflammatory disease has not been reported before in patients with optic atrophy.
April 2021Endovascular Removal of Thrombus and Right Heart Masses Using the AngioVac System: Results of 234 Patients from the Prospective, Multicenter Registry of AngioVac Procedures in Detail (RAPID).
Moriarty JM, Rueda V, Liao M, Kim GHJ, Rochon PJ, Zayed MA, Lasorda D, Golowa YS, Shavelle DM, Dexter DJ.
PURPOSE: To assess device and procedural safety and technical success associated with the use of the AngioVac System to remove vascular thrombi and cardiac masses. MATERIALS & METHODS: The Registry of AngioVac Procedures in Detail (RAPID) study prospectively collected data for 234 patients receiving treatment with AngioVac at 21 sites between March 2016 and August 2019: 84 (35.9%) with caval thromboemboli (CTEs), 113 (48.3%) with right heart masses (RHMs), 20 (8.5%) with catheter-related thrombi (CRTs), and 4 (1.7%) with pulmonary emboli (PEs). Thirteen patients had a combination of procedures during the same admission.
April 2021Role of Intravenous Tissue Plasminogen Activator in Acute Ischemic Stroke with Large Vessel Occlusion.
Ooi YC, Miremadi BB, Mukarram F, Kaneko N, Nour M, Colby G, Jahan R, Tateshima S, Duckwiler G, Saver J, Szeder V.
OBJECTIVE: The goal of the present study was to determine the safety and efficacy of intravenous tissue plasminogen activator (IVT) in patients with acute ischemic stroke (AIS) with large vessel occlusion (LVO) undergoing mechanical thrombectomy (MT). METHODS: We performed a retrospective analysis of prospectively collected data gathered during a 3-year period for all our patients with AIS and LVO. We analyzed the stroke outcomes and complications between patients who had received a combination of IVT and MT and those who had undergone MT only. Standardized selection criteria, including the uniform use of perfusion imaging, were used for selection for MT, irrespective of IVT administration.
April 2021Dynamic Fluoroscopic Defecography: Updates on Rationale, Technique, and Interpretation from the Society of Abdominal Radiology Pelvic Floor Disease Focus Panel.
Palmer SL, Lalwani N, Bahrami S, Scholz F.
Whether used as the primary diagnostic test or reserved as a problem-solving examination, fluoroscopic defecography (FD) remains an important tool in the workup and treatment of defecatory disorders. FD is a well-established, simple, and rapid examination that most closely resembles the actual process and position that a patient uses to enable defecation and provides both qualitative and quantitative information on the defecatory process. FD is indicated when re-creating the act of defecation is necessary, especially in patients with symptoms of obstructed defecation and where symptoms do not correlate with prior examinations such as MRI. Also, FD may help the patient understand the severity of their condition, better informing them of the structural and functional pathology, and aid in discussions with the surgeon regarding plans for treating their complex pelvic floor and defecatory problems. This review provides an up-to-date, comprehensive summary of FD and describes the indications for, techniques of, and common pathology encountered.
April 2021How to Develop and Sustain a Successful Pelvic Floor MRI Practice.
Steiner A, Marks R, Bahrami S, Arif-Tiwari H.
PURPOSE: Magnetic resonance imaging (MRI) of the pelvic floor has become a commonly requested diagnostic tool for pelvic floor assessment. We provide a practical guide for developing, growing, and troubleshooting a dedicated pelvic floor imaging service. METHODS: The authors provide an organized approach to the development of a pelvic floor MRI program based on the experience of the SAR Pelvic Floor Disease Focused Panel in academic and private practice settings. Topics addressed include creating interest, staff education, patient preparation both before and after arrival to the imaging center, image acquisition, reporting, and troubleshooting.
March 2021Denosumab Treatment for Giant Cell Tumor of the Spine Including the Sacrum.
Bukata SV, Blay JY, Rutkowski P, Skubitz K, Henshaw R, Seeger L, Dai T, Jandial D, Chawla S.
STUDY DESIGN: This was a subanalysis of an international, multicenter, open-label study. OBJECTIVE: The aim of this study was to assess the efficacy and safety of denosumab in a subset of patients with giant cell tumors of bone (GCTB) of the spine including the sacrum from an international, open-label, single-arm, phase 2 study (ClinicalTrials.gov: NCT00680992). SUMMARY OF BACKGROUND DATA: Standard GCTB treatment is surgical removal, either by curettage or resection, combined with intraoperative adjuvant therapy; however, some sites may not be amenable to resection (e.g., skull, spine). METHODS: Adults or skeletally mature adolescents with pathologically confirmed GCTB of the spine including the sacrum, and radiologically measurable evidence of active disease, were included. Patients received denosumab (120 mg subcutaneously) once every 4 weeks during the treatment phase, with loading doses on days 8 and 15 of the first cycle. Patients had surgically unsalvageable GCTB (Cohort 1), had planned surgery expected to result in severe morbidity (Cohort 2), or were enrolled from a previous GCTB study (Cohort 3).
March 2021Concomitant AngioVac Thrombectomy and Patent Foramen Ovale Closure in a Patient with a Large Right Atrial Thrombus and Recent Paradoxical Embolic Stroke.
Callese TE, Yang EH, Levi D, Srinivasa RN, Moriarty JM.
A 59-year-old male with a history of gallbladder adenocarcinoma receiving chemotherapy and on therapeutic anticoagulation for portal vein thrombosis presented to the emergency department via ambulance after being found unresponsive and in cardiac arrest. Initial workup upon return of spontaneous circulation revealed a large right atrial mass, patent foramen ovale (PFO), and bilateral acute cortical infarctions. This constellation of findings were concerning for PFO-related paradoxical embolic strokes. Given the risk of recurrent paradoxical embolic events and the absolute contraindication to thrombolysis due to recent cerebral infarction, the decision was made to proceed with percutaneous vacuum-assisted thrombectomy using the AngioVac device. To prevent intraoperative thrombus propagation, PFO-closure was performed immediately prior to thrombectomy. Aspiration thrombectomy and PFO-closure were successful with complete thrombus removal and no intraoperative thrombus propagation. This case presents a minimally invasive and rapid treatment for a complex problem. An efficient and effective interdisciplinary team-based approach allowed the patient to resume cancer treatment relatively unabated.
March 2021Unique Challenges for Glioblastoma Immunotherapy-discussions Across Neuro-Oncology and Non-neuro-oncology Experts in Cancer Immunology. Meeting Report from the 2019 SNO Immuno-Oncology Think Tank.
Chuntova P, Chow F, Watchmaker PB, Galvez M, Heimberger AB, Newell EW, Diaz A, DePinho RA, Li MO, Wherry EJ, Mitchell D, Terabe M, Wainwright DA, Berzofsky JA, Herold-Mende C, Heath JR, Lim M, Margolin KA, Chiocca EA, Kasahara N, Ellingson BM, Brown CE, Chen Y, Fecci PE, Reardon DA, Dunn GP, Liau LM, Costello JF, Wick W, Cloughesy T, Timmer WC, Wen PY, Prins RM, Platten M, Okada H.
Cancer immunotherapy has made remarkable advances with over 50 separate Food and Drug Administration (FDA) approvals as first- or second-line indications since 2015. These include immune checkpoint blocking antibodies, chimeric antigen receptor-transduced T cells, and bispecific T-cell-engaging antibodies. While multiple cancer types now benefit from these immunotherapies, notable exceptions thus far include brain tumors, such as glioblastoma. As such, it seems critical to gain a better understanding of unique mechanistic challenges underlying the resistance of malignant gliomas to immunotherapy, as well as to acquire insights into the development of future strategies. An Immuno-Oncology Think Tank Meeting was held during the 2019 Annual Society for Neuro-Oncology Scientific Conference. Discussants in the fields of neuro-oncology, neurosurgery, neuro-imaging, medical oncology, and cancer immunology participated in the meeting. Sessions focused on topics such as the tumor microenvironment, myeloid cells, T-cell dysfunction, cellular engineering, and translational aspects that are critical and unique challenges inherent with primary brain tumors. In this review, we summarize the discussions and the key messages from the meeting, which may potentially serve as a basis for advancing the field of immune neuro-oncology in a collaborative manner.
March 2021Society of Interventional Radiology Quality Improvement Standards for Percutaneous Transcatheter Embolization.
Dariushnia SR, Redstone EA, Heran MKS, Cramer HR Jr, Ganguli S, Gomes AS, Hogan MJ, Himes EA, Patel S, Schiro BJ, Lewis CA.
Percutaneous embolization procedures are commonly performed by interventional radiologists. This quality improvement (QI) standard was first published in 2010 (1), and this document represents the second update. Since the 2010 standards, many additional randomized controlled trials, meta-analyses, and observational studies have been published on transcatheter embolization for various disease entities, further establishing embolization as an effective treatment. Additionally, the indications of embolization have expanded with newer procedures, like prostatic embolization for benign prostatic hyperplasia (BPH), and emerging procedures, such as left gastric artery embolization for the treatment of obesity and genicular artery embolization for the treatment of pain related to osteoarthritis (OA). This revised document includes a discussion on the performance of embolization procedures in pediatric patients, emphasizes the current literature, and builds upon previous documents to provide up-to-date information to ensure effective, safe, and high-quality care.
March 2021Cryoablation for Palliation of Painful Bone Metastases: The MOTION Multicenter Study.
Jennings JW, Prologo JD, Garnon J, Gangi A, Buy X, Palussière J, Kurup AN, Callstrom M, Genshaft S, Abtin F, Huang AJ, Iannuccilli J, Pilleul F, Mastier C, Littrup PJ, de Baère T, Deschamps F.
PURPOSE: To assess the clinical effectiveness of cryoablation for palliation of painful bone metastases. MATERIALS & METHODS: MOTION (Multicenter Study of Cryoablation for Palliation of Painful Bone Metastases) (ClinicalTrials.gov NCT02511678) was a multicenter, prospective, single-arm study of adults with metastatic bone disease who were not candidates for or had not benefited from standard therapy, that took place from February 2016 to March 2018. At baseline, participants rated their pain using the Brief Pain Inventory-Short Form (reference range from 0 to 10 points); those with moderate to severe pain, who had at least one metastatic candidate tumor for ablation, were included. The primary effectiveness endpoint was change in pain score from baseline to week 8. Participants were followed for 24 weeks after treatment. Statistical analyses included descriptive statistics and logistic regression to evaluate changes in pain score over the postprocedure follow-up period.
March 2021Prospect of Artificial Intelligence for the Assessment of Cardiac Function and Treatment of Cardiovascular Disease.
Kheradvar A, Jafarkhani H, Guy TS, Finn JP.
During the past decade, artificial intelligence (AI) has become sufficiently advanced to begin impacting many aspects of the human life. Applications of AI in medicine have currently been limited to the gears that facilitate physicians' tasks and improve their clinical workflow. In cardiovascular medicine, AI has been integrated into software that facilitate data analysis used in research and development, diagnostic imaging and population health.
March 2021Magnetic Resonance Imaging-Guided Transurethral Ultrasound Ablation of Prostate Cancer.
Klotz L, Pavlovich CP, Chin J, Hatiboglu G, Koch M, Penson D, Raman S, Oto A, Fütterer J, Serrallach M, Relle J, Lotan Y, Heidenreich A, Bonekamp D, Haider M, Tirkes T, Arora S, Macura KJ, Costa DN, Persigehl T, Pantuck AJ, Bomers J, Burtnyk M, Staruch R, Eggener S.
PURPOSE: Magnetic resonance imaging-guided transurethral ultrasound ablation uses directional thermal ultrasound under magnetic resonance imaging thermometry feedback control for prostatic ablation. We report 12-month outcomes from a prospective multicenter trial (TACT). MATERIALS AND METHODS: A total of 115 men with favorable to intermediate risk prostate cancer across 13 centers were treated with whole gland ablation sparing the urethra and apical sphincter. The co-primary 12-month endpoints were safety and efficacy.
March 2021Image-Guided Biopsies and Interventions of Mediastinal Lesions.
Kooraki S, Abtin F.
Optimal assessment of the mediastinal masses is performed by a combination of clinical, radiological and often histological assessments. Image-guided transthoracic biopsy of mediastinal lesions is a minimally invasive and reliable procedure to obtain tissue samples, establish a diagnosis and provide a treatment plan. Biopsy can be performed under Computed Tomography, MRI, or ultrasound guidance, using a fine needle aspiration or a core-needle. In this paper, we review the image-guided strategies and techniques for histologic sampling of mediastinal lesions, along with the related clinical scenarios and possible procedural complications. In addition, image-guided mediastinal drainage and mediastinal ablations will be briefly discussed.
March 2021The Role of PSMA PET/CT and PET/MRI in the Initial Staging of Prostate Cancer.
Murthy V, Sonni I, Jariwala N, Juarez R, Reiter RE, Raman SS, Hope TA.
CONTEXT: Prostate cancer (PCa) is the most common solid organ malignancy in men and is the third leading cause of cancer death. Accurate methods for the detection and staging of PCa are necessary to determine the extent of disease and inform treatment options. OBJECTIVE: To review the performance and diagnostic accuracy of prostate-specific membrane antigen (PSMA) positron emission tomography (PET) imaging in the initial staging of PCa and evaluate its impact on definitive therapy planning. EVIDENCE ACQUISITION: A comprehensive literature search was performed using PubMed. References from retrieved articles and recommendations from the authors were also included.
March 2021Rapid Measurement of the Low Contrast Detectability of CT Scanners.
Omigbodun A, Vaishnav JY, Hsieh SS.
PURPOSE: Low contrast detectability (LCD) is a metric of fundamental importance in computed tomography (CT) imaging. In spite of this, its measurement is challenging in the context of nonlinear data processing. We introduce a new framework for objectively characterizing LCD with a single scan of a special-purpose phantom and automated analysis software. The output of the analysis software is a "machine LCD" metric which is more representative of LCD than contrast-noise ratio (CNR). It is not intended to replace human observer or model observer studies. METHODS: Following preliminary simulations, we fabricated a phantom containing hundreds of low-contrast beads. These beads are acrylic spheres (1.6 mm, net contrast ~10 HU) suspended and randomly dispersed in a background matrix of nylon pellets and isoattenuating saline. The task was to search for and localize the beads. A modified matched filter was used to automatically scan the reconstruction and select candidate bead localizations of varying confidence. These were compared to bead locations as determined from a high-dose reference scan to produce free-response ROC curves. We compared iterative reconstruction (IR) and filtered backpropagation (FBP) at multiple dose levels between 40 and 240 mAs. The scans at 60, 120, and 180 mAs were performed three times each to estimate uncertainty.
March 2021Birt-Hogg-Dubé Syndrome Presenting with Chronic Progressive Dyspnea.
Reilly D, Pourzand L, Chima-Melton C.
Birt-Hogg-Dubé Syndrome (BHDS) is a rare autosomal dominant disease which manifests with cutaneous hamartomas, lung cysts and renal carcinomas. A wide spectrum of phenotypic expression and few visible manifestations makes BHDS a likely under-recognized entity. Diffuse cystic lung disease (DCLD) is the typical pulmonary manifestation of BHDS, which in the absence of other specific findings carries a broad differential diagnosis. Unlike many other causes of DCLD, BHDS is not known to present with symptomatic pulmonary dysfunction. We report a typical case of BHDS with an atypical presentation - chronic progressive dyspnea. The unusual presentation provides an opportunity to discuss the differential for DCLD and highlights the importance of maintaining an index of suspicion for BHDS even when symptoms appear inconsistent with the diagnosis. Also examined is the management of BHDS patients and their immediate relatives, and recommendations for the treatment of obstructive sleep apnea (OSA) with continuous positive airway pressure (CPAP) given the potential risk of pneumothorax in this group.
March 2021A Framework for Sharing Radiation Dose Distribution Maps in the Electronic Medical Record for Improving Multidisciplinary Patient Management.
Savjani RR, Salamon N, Deng J, Ma M, Tenn S, Agazaryan N, Hegde J, Kaprealian T.
Radiation oncology practices use a suite of dedicated software and hardware that are not common to other medical subspecialties, making radiation treatment history inaccessible to colleagues. A radiation dose distribution map is generated for each patient internally that allows for visualization of the dose given to each anatomic structure volumetrically; however, this crucial information is not shared systematically to multidisciplinary medical, surgery, and radiology colleagues. A framework was developed in which dose distribution volumes are uploaded onto the medical center's picture archiving and communication system (PACS) to rapidly retrieve and review exactly where, when, and to what dose a lesion or structure was treated. The ability to easily visualize radiation therapy information allows radiology clinics to incorporate radiation dose into image interpretation without direct access to radiation oncology planning software and data. Tumor board discussions are simplified by incorporating radiation therapy information collectively in real time, and daily onboard imaging can also be uploaded while a patient is still undergoing radiation therapy. Placing dose distribution information into PACS facilitates central access into the electronic medical record and provides a succinct visual summary of a patient's radiation history for all medical providers. More broadly, the radiation dose map provides greater visibility and facilitates incorporation of a patient's radiation history to improve oncologic decision making and patient outcomes.
March 202168Ga-FAPi-46 Diffuse Bilateral Breast Uptake in a Patient with Cervical Cancer After Hormonal Stimulation.
Sonni I, Lee-Felker S, Memarzadeh S, Quinn MM, Mona CE, Lückerath K, Czernin J, Calais J.
A 36-year-old female patient diagnosed with invasive squamous cell carcinoma of the cervix underwent an 18F-fluorodeoxyglucose ([18F]FDG) PET/CT scan for presurgical staging.
March 2021Voxelwise and Patientwise Correlation of 18F-FDOPA PET, Relative Cerebral Blood Volume, and Apparent Diffusion Coefficient in Treatment-Naïve Diffuse Gliomas with Different Molecular Subtypes.
Tatekawa H, Hagiwara A, Yao J, Oughourlian TC, Ueda I, Uetani H, Raymond C, Lai A, Cloughesy TF, Nghiemphu PL, Liau LM, Pope WB, Salamon N, Ellingson BM.
Our purpose was to identify correlations between 18F-fluorodihydroxyphenylalanine (18F-FDOPA) uptake and physiologic MRI, including relative cerebral blood volume (rCBV) and apparent diffusion coefficient (ADC), in gliomas with different molecular subtypes and to evaluate their prognostic values. METHODS: Sixty-eight treatment-naïve glioma patients who underwent 18F-FDOPA PET and physiologic MRI were retrospectively selected (36 with isocitrate dehydrogenase wild-type [IDHwt], 16 with mutant 1p/19q noncodeleted [IDHm-noncodel], and 16 with mutant codeleted [IDHm-codel]). Fluid-attenuated inversion recovery hyperintense areas were segmented and used as regions of interest. For voxelwise and patientwise analyses, Pearson correlation coefficients (r voxelwise and r patientwise) between the normalized SUV (nSUV), rCBV, and ADC were evaluated. Cox regression analysis was performed to investigate the associations between overall survival and r voxelwise, maximum or median nSUV, median rCBV, or median ADC.
February 2021Case 286: Sarcoidlike Granulomatosis and Lymphadenopathy-Thoracic Manifestations of Nivolumab Drug Toxicity.
Chiang J, Hebroni F, Bedayat A, Pourzand L.
History A 70-year-old man had a posterior left thigh lesion confirmed to be biopsy-proven melanoma. The patient underwent wide excision and sentinel node biopsy, which showed absence of residual melanoma. Two years later, the patient noticed a subcentimeter subcutaneous lump in his thigh. Repeat excisional biopsy showed involvement of the surrounding soft tissue, consistent with a satellite lesion. Follow-up combined PET/CT revealed satellite nodules around the primary lesion, enabling confirmation of subcutaneous metastatic disease. The patient was subsequently started on nivolumab, an anti-programmed cell death 1 (PD-1) immune checkpoint inhibitor that blocks PD-1 and is approved as a first-line treatment in patients with advanced metastatic melanoma. On the baseline scan prior to starting nivolumab, there were no CT findings that suggested metastatic disease, nor were there enlarged mediastinal or hilar lymph nodes. Five months after initiation of nivolumab treatment, the first follow-up chest CT scan was performed and showed new findings in the mediastinum and bilateral lungs. The patient remained asymptomatic during the treatment period. Furthermore, the subcutaneous metastatic disease remained stable during the treatment period, and no other site of metastatic disease was noted on follow-up CT scans obtained during the first 5 months of treatment. The patient had no prior history of infectious or occupational exposures. During the nivolumab treatment cycle, his pertinent laboratory values and physical examination findings were unremarkable.
February 2021Radiographic Read Paradigms and the Roles of the Central Imaging Laboratory in Neuro-oncology Clinical Trials.
Ellingson BM, Brown MS, Boxerman JL, Gerstner ER, Kaufmann TJ, Cole PE, Bacha JA, Leung D, Barone A, Colman H, van den Bent MJ, Wen PY, Alfred Yung WK, Cloughesy TF, Goldin JG.
Determination of therapeutic benefit in intracranial tumors is intimately dependent on serial assessment of radiographic images. The Response Assessment in Neuro-Oncology (RANO) criteria were established in 2010 to provide an updated framework to better characterize tumor response to contemporary treatments. Since this initial update a number of RANO criteria have provided some basic principles for the interpretation of changes on MR images; however, the details of how to operationalize RANO and other criteria for use in clinical trials are ambiguous and not standardized. In this review article designed for the neuro-oncologist or treating clinician, we outline essential steps for performing radiographic assessments by highlighting primary features of the Imaging Charter (referred to as the Charter for the remainder of this article), a document that describes the clinical trial imaging methodology and methods to ensure operationalization of the Charter into the workings of a clinical trial. Lastly, we provide recommendations for specific changes to optimize this methodology for neuro-oncology, including image registration, requirement of growing tumor for eligibility in trials of recurrent tumor, standardized image acquisition guidelines, and hybrid reader paradigms that allow for both unbiased measurements and more comprehensive interpretation.
February 2021Using Digital Ethnography to Understand the Experience of Women With Pelvic Organ Prolapse.
Gonzalez G, Vaculik K, Khalil C, Zektser Y, Arnold C, Almario CV, Spiegel BMR, Anger JT.
OBJECTIVE: To characterize the decision-making process and illness experience of women with pelvic organ prolapse (POP) using large-scale social media analysis. METHODS: Digital ethnographic analysis of online posts identified through data mining was performed. Grounded theory methodology was applied to 200 posts via traditional hand coding. To supplement our qualitative approach, we applied a Latent Dirichlet Allocation probabilistic topic modeling process to review the entire data set of identified posts to ensure thematic saturation.
February 2021VIDEO: Dynamic Ultrasound for Snapping Hip Syndrome.
Levine BD, Kwong S, Motamedi K.
OBJECTIVE: The purpose of this video article is to review the dynamic sonographic assessment of snapping hip syndrome. The video focuses on the extraarticular forms of snapping hip and discusses their possible causes, ultrasound features, and treatment options. The dynamic sonographic technique for evaluating snapping hip syndrome is shown with live scanning videos.
February 2021Predicting Pathological Tumor Size in Prostate Cancer Based on Multiparametric Prostate Magnetic Resonance Imaging and Preoperative Findings.
Pooli A, Johnson DC, Shirk J, Markovic D, Sadun TY, Sisk AE Jr, Mohammadian Bajgiran A, Afshari Mirak S, Felker ER, Hughes AK, Raman SS, Reiter RE.
PURPOSE: Oncologic efficacy of focal therapies in prostate cancer depends heavily on accurate tumor size estimation. We aim to evaluate the agreement between radiologic tumor size and pathological tumor size, and identify predictors of pathological tumor size. MATERIALS AND METHODS: This single arm study cohort included all consecutive patients with biopsy proven prostate cancer and a corresponding PI-RADS®v2 3 or greater index tumor on multiparametric magnetic resonance imaging who subsequently underwent radical prostatectomy. Radiologic tumor size was defined as maximum tumor diameter on multiparametric magnetic resonance imaging and compared to whole mount histopathology tumor correlates. The difference between radiologic tumor size and pathological tumor size was assessed, and clinical, pathological and radiographic predictors of pathological tumor size were examined.
February 2021Treatment of Post-Ablation Bronchopleural Fistula Using Percutaneous Synthetic Hydrogel Surgical Sealant: Initial Experience of Safety and Efficacy.
Shahrouki P, Barclay J, Khan S, Genshaft S, Abtin F, McGraw C, Baek D, Nickel B, Suh R.
PURPOSE: Bronchopleural fistula is a rare but serious complication of lung ablation, as it is difficult to treat and is associated with a high mortality rate. Standard therapy often relies on surgical pleurodesis, which can be particularly problematic in patients with poor baseline lung function. A minimally invasive treatment option for bronchopleural fistula may offer an alternative to surgery for appropriate patients. This case series describes the technique, safety and efficacy of percutaneously administered synthetic hydrogel surgical sealant in the treatment of post-ablation bronchopleural fistula in five patients. MATERIALS AND METHODS: Retrospective chart review was carried out in five consecutive patients identified to have had BPF after lung ablation between 2009 and 2017 who were treated with percutaneous administration of synthetic hydrogel surgical sealant using CT guidance.
February 2021Influence of Phosphate Concentration on Amine, Amide, and Hydroxyl CEST Contrast.
Yao J, Wang C, Ellingson BM.
PURPOSE: To evaluate the influence of phosphate on amine, amide, and hydroxyl CEST contrast using Bloch-McConnell simulations applied to physical phantom data. METHODS: Phantom solutions of 4 representative metabolites with exchangeable protons-glycine (α-amine protons), Cr (η-amine protons), egg white protein (amide protons), and glucose (hydroxyl protons)-were prepared at different pH levels (5.6 to 8.9) and phosphate concentrations (5 to 80 mM). CEST images of the phantom were collected with CEST-EPI sequence at 3 tesla. The CEST data were then fitted to full Bloch-McConnell equation simulations to estimate the exchange rate constants. With the fitted parameters, simulations were performed to evaluate the intracellular and extracellular contributions of CEST signals in normal brain tissue and brain tumors, as well as in dynamic glucose-enhanced experiments.
January 2021Eigenrank by Committee: Von-Neumann Entropy Based Data Subset Selection and Failure Prediction for Deep Learning Based Medical Image Segmentation.
Gaonkar B, Beckett J, Attiah M, Ahn C, Edwards M, Wilson B, Laiwalla A, Salehi B, Yoo B, Bui AAT, Macyszyn L.
Manual delineation of anatomy on existing images is the basis of developing deep learning algorithms for medical image segmentation. However, manual segmentation is tedious. It is also expensive because clinician effort is necessary to ensure correctness of delineation. Consequently most algorithm development is based on a tiny fraction of the vast amount of imaging data collected at a medical center. Thus, selection of a subset of images from hospital databases for manual delineation - so that algorithms trained on such data are accurate and tolerant to variation, becomes an important challenge. We address this challenge using a novel algorithm. The proposed algorithm named 'Eigenrank by Committee' (EBC) first computes the degree of disagreement between segmentations generated by each DL model in a committee. Then, it iteratively adds to the committee, a DL model trained on cases where the disagreement is maximal. The disagreement between segmentations is quantified by the maximum eigenvalue of a Dice coefficient disagreement matrix a measure closely related to the Von Neumann entropy. We use EBC for selecting data subsets for manual labeling from a larger database of spinal canal segmentations as well as intervertebral disk segmentations. U-Nets trained on these subsets are used to generate segmentations on the remaining data. Similar sized data subsets are also randomly sampled from the respective databases, and U-Nets are trained on these random subsets as well. We found that U-Nets trained using data subsets selected by EBC, generate segmentations with higher average Dice coefficients on the rest of the database than U-Nets trained using random sampling (p < 0.05 using t-tests comparing averages). Furthermore, U-Nets trained using data subsets selected by EBC generate segmentations with a distribution of Dice coefficients that demonstrate significantly (p < 0.05 using Bartlett's test) lower variance in comparison to U-Nets trained using random sampling for all datasets. We believe that this lower variance indicates that U-Nets trained with EBC are more robust than U-Nets trained with random sampling.
January 2021[Future of Cerebral Aneurysm Treatment].
Kaneko N, Tateshima S.
There has been an increasing role in the low invasive endovascular treatment of intracranial aneurysms. In addition to the detachable coils, the development of intracranial stents that are capable of repairing the parent artery itself has induced a significant treatment paradigm shift from open surgical to endovascular intervention. Recent evidence suggests that chronic inflammation plays a critical role in the process of intracranial aneurysm formation and rupture. It is, therefore, a natural evolution to seek drug treatments for intracranial aneurysms for growth or rupture prevention rather than any mechanical intervention. The authors review the current preclinical efforts on aneurysm drug treatments and prospective. Also covered is an emerging technology such as robotic endovascular treatment. The robotic system is capable of performing a subset of endovascular procedures such as stent-assisted aneurysm coiling. Although a lot of work needs to be done, remote health care is no longer science fiction.
January 2021Call for a New Radiology Subspecialty in Imaging-Based Screening.
Milch HS, Haramati LB.
Imaging-based screening has become a critical component of preventive care medicine, growing immensely over the past 50 years. Radiologists are at the center of this public health practice—we are the imaging experts—and yet we are underrepresented in the decision-making process that directs national screening practices. These decisions are largely made by primary care professionals and epidemiologists, who lack expertise in imaging. Here are two possible reasons for this: (1) Radiologists currently have minimal training in epidemiology and evidence development related to imaging-based screening, and (2) radiologists may be viewed as fundamentally biased in favor of imaging, resulting in a daily incentive toward more screening. As a solution, we propose a new radiology subspecialty—screening radiology—to help close the educational gap, untangle advocacy from science, and enable more effective radiology leadership in screening.
January 2021Cardiac Magnetic Resonance Quantification of Structure-Function Relationships in Heart Failure.
Nguyen KL, Hu P, Finn JP.
Classification of heart failure is based on the left ventricular ejection fraction (EF): preserved EF, midrange EF, and reduced EF. There remains an unmet need for further heart failure phenotyping of ventricular structure-function relationships. Because of high spatiotemporal resolution, cardiac magnetic resonance (CMR) remains the reference modality for quantification of ventricular contractile function. The authors aim to highlight novel frameworks, including theranostic use of ferumoxytol, to enable more efficient evaluation of ventricular function in heart failure patients who are also frequently anemic, and to discuss emerging quantitative CMR approaches for evaluation of ventricular structure-function relationships in heart failure.
January 2021PI-RADS Version 2.1: A Critical Review, From the AJR Special Series on Radiology Reporting and Data Systems.
Purysko AS, Baroni RH, Giganti F, Costa D, Renard-Penna R, Kim CK, Raman SS.
PI-RADS version 2.1 updates the technical parameters for multiparametric MRI (mpMRI) of the prostate and revises the imaging interpretation criteria while maintaining the framework introduced in version 2. These changes have been considered an improvement, although some issues remain unresolved, and new issues have emerged. Areas for improvement discussed in this review include the need for more detailed mpMRI protocols with optimization for 1.5-T and 3-T systems; lack of validation of revised transition zone interpretation criteria and need for clarifications of the revised DWI and dynamic contrast-enhanced imaging criteria and central zone (CZ) assessment; the need for systematic evaluation and reporting of background changes in signal intensity in the prostate that can negatively affect cancer detection; creation of a new category for lesions that do not fit into the PI-RADS assessment categories (i.e., PI-RADS M category); inclusion of quantitative parameters beyond size to evaluate lesion aggressiveness; adjustments to the structured report template, including standardized assessment of the risk of extraprostatic extension; development of parameters for image quality and performance control; and suggestions for expansion of the system to other indications (e.g., active surveillance and recurrence).