The Brain Tumor Segmentation (BraTS-METS) Challenge 2023: Brain Metastasis Segmentation on Pre-treatment MRI.

Clinical monitoring of metastatic disease to the brain can be a laborious and timeconsuming process, especially in cases involving multiple metastases when the assessment is performed manually. The Response Assessment in Neuro-Oncology Brain Metastases (RANO-BM) guideline, which utilizes the unidimensional longest diameter, is commonly used in clinical and research settings to evaluate response to therapy in patients with brain metastases. However, accurate volumetric assessment of the lesion and surrounding peri-lesional edema holds significant importance in clinical decision-making and can greatly enhance outcome prediction. The unique challenge in performing segmentations of brain metastases lies in their common occurrence as small lesions. Detection and segmentation of lesions that are smaller than 10 mm in size has not demonstrated high accuracy in prior publications. The brain metastases challenge sets itself apart from previously conducted MICCAI challenges on glioma segmentation due to the significant variability in lesion size. Unlike gliomas, which tend to be larger on presentation scans, brain metastases exhibit a wide range of sizes and tend to include small lesions. We hope that the BraTS-METS dataset and challenge will advance the field of automated brain metastasis detection and segmentation.

PEBAT, an Intriguing Neurodegenerative Tubulinopathy Caused by a Novel Homozygous Variant in TBCD: A Case Series and Literature Review.

Progressive encephalopathy with brain atrophy and thin corpus callosum (PEBAT) is a severe and rare progressive neurodegenerative disease (OMIM 617913). This condition has been described in individuals with pathogenic variants affecting tubulin-specific chaperone protein D (TBCD), which is responsible for proper folding and assembly of tubulin subunits. Here we describe two unrelated infants from Central America presenting with worsening neuromuscular weakness, respiratory failure, polyneuropathy, and neuroimaging findings of severe cerebral volume loss with thin corpus callosum. These individuals harbored the same homozygous variant of uncertain significance in the TBCD gene on whole exome sequencing (WES). Predicted protein modeling of this variant confirmed disruption of the protein helix at the surface of TBCD. The goal of this report is to emphasize the importance of rapid WES, careful interpretation of uncertain variants, prognostication, and family counseling especially when faced with a neurodegenerative clinical course.

Multiple Endocrine Neoplasia Type 1: A Case Report With Review of Imaging Findings.

BACKGROUND: Multiple endocrine neoplasia type 1 (MEN1) is a rare, autosomal dominant inherited syndrome caused by mutations in the MEN1 tumor suppressor gene. The diagnosis is defined clinically by the presence of 2 or more primary MEN1 tumors (parathyroid, anterior pituitary, and pancreatic islet). We describe the case of a patient who presented with classic history and imaging findings for MEN1. CASE REPORT: A male in his early thirties with a history of hyperparathyroidism and a transsphenoidal prolactinoma resection presented years later with abdominal symptoms concerning for Zollinger-Ellison syndrome: worsening epigastric abdominal pain, nausea, vomiting, and diarrhea. Contrast-enhanced computed tomography (CT) of the abdomen revealed hyperenhancing pancreatic lesions and duodenal inflammation, suggesting pancreatic neuroendocrine tumor (gastrinoma) with secondary duodenitis. Bilateral indeterminate hypoattenuating adrenal nodules were also seen on contrast-enhanced CT, and follow-up magnetic resonance imaging confirmed benign adrenal adenomas. Furthermore, thyroid ultrasound and sestamibi scintigraphy revealed a parathyroid adenoma. With confirmatory imaging findings, history, and presenting symptoms, the patient was clinically diagnosed with MEN1 syndrome and underwent surgical and medical management. CONCLUSION: This case exhibits the classic history with corresponding imaging findings of MEN1 syndrome, including pancreatic neuroendocrine tumors, parathyroid adenoma, and adrenal adenomas. High clinical suspicion for MEN1 should lead to endocrinology evaluation with appropriate laboratory workup and targeted imaging evaluation of the typical endocrine organs as described for this patient.

Day of Week, Site of Service, and Patient Complexity Disparities in Musculoskeletal MRI Interpretations by Radiologists Versus Nonradiologists.

OBJECTIVE: Although most musculoskeletal MRI examinations are interpreted by radiologists, some nonradiologists provide interpretations as well. We aimed to study day of week (weekday vs weekend), site of service, and patient complexity differences between radiologists and nonradiologists interpreting lower extremity MRI examinations on Medicare beneficiaries. MATERIALS AND METHODS: Using fee-for-service carrier claims for a 5% sample of Medicare beneficiaries nationally from 2012 through 2014, we identified all lower extremity joint MRI examinations. Services were classified by physician specialty, day of week, and site of service. Charlson comorbidity index (CCI) values were calculated for all patients. Chi-square statistical testing was performed. RESULTS: Of all 125,800 billed lower extremity joint MRI examinations, 118,295 (94.0%) were performed on weekdays and 7505 (6.0%) on weekends. Of the weekday examinations, radiologists interpreted 85,991 (83.3%) and nonradiologists 17,260 (16.7%). Of the weekend examinations, radiologists interpreted 6212 (92.8%) and nonradiologists 485 (7.2%). Of examinations performed in inpatient hospital and emergency department settings, radiologists interpreted 6499 (99.2%) and nonradiologists 51 (0.8%). Of the examinations on the most clinically complex patients (CCI ≥ 3), radiologists interpreted 4228 (90.2%) and nonradiologists 461 (9.8%). All interspecialty differences were statistically significant (p < 0.001). CONCLUSION: In the Medicare population, radiologists interpret most lower extremity joint MRI examinations. Compared with nonradiologists, radiologists disproportionately provide services on weekends, in the highest acuity settings, and on the most clinically complex patients. To promote patient access and minimize disparities, future pay-for-performance metrics should consider temporal, acuity, and complexity parameters.

2017 ACR Annual Meeting Open-Microphone Session: Navigating the Landscape of Changing Practice Models: Private Practice, Corporate Radiology, and Enterprise Systems.

Many practice groups are considering adopting new practice models, primarily to secure their practices by adapting to new payment models, government compliance and regulation, and increasing IT and infrastructure costs. As we move toward value-based care and capitation, the value equation (value = quality/cost) will lead us to also compete on cost to improve value. No matter what payment models ultimately dominate, we need to be prepared to lead in a value-based care environment. Measures of value will either be defined by radiologists or imposed by outside entities. It is critical to our continued success that practices and practice leaders continue to fully and strongly support the ACR to avoid the possibility of a decline in membership that may accompany a lack of practice engagement. Consolidation appears inevitable, but with the help of the ACR, radiologists should have a vibrant future if investments are made now in determining appropriate radiology-specific value measures that are meaningful in consolidated health care environments.

The imaging appearance of crayons.

BACKGROUND: A crayon fragment was determined to be the source of a foreign body inflammatory process in the masticator space of a 15-month-old boy. The appearance of the crayon on CT and MR imaging was unexpected, leading to a further analysis of the imaging features of crayons. OBJECTIVE: To investigate and characterize the imaging appearance of crayons at CT and MRI. MATERIALS AND METHODS: The authors obtained CT and MR images of 22 crayons from three manufacturers and three non-pigmented crayons cast by the authors. CT attenuation of the crayons and diameter of the MRI susceptibility signal dropout were plotted versus brand and color. RESULTS: All crayons demonstrated a longitudinal central hypo-attenuating tract. Crayon attenuation varied by brand and color. All of the crayons demonstrated a signal void on T1 and T2 imaging and signal dropout on susceptibility-weighted imaging, the diameter of which varied by brand and color. CONCLUSION: Understanding the imaging appearance of crayons could help in the correct identification of a crayon as a foreign body on imaging studies, even when it is located in unusual places.

Hoverboards: spectrum of injury and association with an uncommon fracture.

BACKGROUND: Self-balancing electric scooters, commonly known as hoverboards, are a new and popular consumer item with recognized fall hazards. The spectrum of injuries associated with hoverboard use has not been studied. OBJECTIVE: The purpose of this study is to determine the spectrum of radiologically apparent injuries associated with hoverboard use. MATERIALS AND METHODS: We retrospectively reviewed all imaging studies interpreted at our institution for hoverboard-related injuries during an 8-month period. We recorded patient demographics and injury characteristics. RESULTS: Thirty-two of the 47 pediatric patients imaged for hoverboard-related injury had radiologically detectable injuries, all fractures. Fifty percent of these 32 patients were female and 50% were male, with a mean age of 12.4 years. There were 42 fractures total, all involving the appendicular skeleton, with 74% in the upper extremities and 26% in the lower extremities. Thirty-eight percent of the fractures involved the physis. A distinct injury pattern was seen in three patients who sustained open distal phalanx juxta-epiphyseal fractures. CONCLUSION: Most of the fractures sustained during hoverboard use are commonly seen in everyday pediatric radiology practice, with an overall pattern paralleling that reported in association with skateboard use. However an otherwise uncommon fracture, the distal phalanx juxta-epiphyseal fracture, was identified in association with hoverboard use, and this finding has important treatment implications including need for irrigation and debridement, antibiotic therapy, and potential surgical fixation.

Double Fellowships in Radiology: A Survey of 2014 Graduating Fellows.

PURPOSE: Radiology fellowship training has evolved from being an uncommon option to being a near requisite for post-training employment in the United States. A subset of fellows elect to pursue second fellowships with potentially substantial implications on both the private sector and academic radiology workforce. The purpose of this study was to assess the proportion of current radiology fellows pursuing multiple years of post-residency fellowship training. MATERIALS AND METHODS: After obtaining IRB approval, an anonymous web-based survey was emailed to 1,269 radiology fellows listed as "completing fellowship" in the American College of Radiology database in June 2014. Questions were asked regarding current fellowship training, post-fellowship employment plans, and individual experience pursuing employment. Results were analyzed using the survey analytical software. RESULTS: There were 219 responses received, representing a 17.3% response rate. Ten-percent of respondents were currently completing their second radiology fellowship. Of those completing their first year of fellowship training, 11% indicated plans to complete a second radiology fellowship. CONCLUSION: This survey provides a snapshot of the percentage of radiology trainees who pursue a second year of fellowship training, currently in the range of 10%. Pursuing a second radiology fellowship may represent a safety net to a substantial subset of fellows who are not able to obtain satisfactory employment following training. Academic programs who rely heavily on fellows should be aware of the proportion of fellows pursuing two fellowships and should be prepared to adapt should this change over time.

Doppler Characteristics of Recurrent Hepatic Artery Stenosis.

OBJECTIVES: We sought to assess midterm sonographic findings in patients after stenting for hepatic artery stenosis. METHODS: Thirty-nine hepatic artery stent procedures were performed for hepatic artery stenosis after liver transplantation between September 2009 and December 2013. Thirty cases were technically successful and met the minimum follow-up time (76 days, defined by earliest diagnosed stenosis). Routine ultrasound surveillance was obtained on all patients, and statistical analysis of the findings in the patency and restenosis groups was performed. RESULTS: Of the 30 cases, restenosis occurred 9 times in 6 patients. Mean follow-up was 677 days. Mean time to restenosis was 267 days. Five cases (56%) were identified within the first 6 months after stent placement. Four cases (44%) were recognized in the second year after stent placement. Prior to the sonographic diagnosis of restenosis, the mean resistive indices of the main (.64 versus .57, P < .0001), left (.63 versus .54, P < .0001), right anterior (.60 versus .52, P < .0001), and right posterior (.60 versus .53, P = .001) hepatic artery branches differed among patency and restenosis groups, respectively. The mean peak systolic velocity also differed significantly between the 2 groups: 254 cm/sec in patients with eventual restenosis versus 220 cm/sec in patients without restenosis (P = .02). CONCLUSIONS: The sonographic evaluation of hepatic artery stenosis remains critical during the first 2 years after stent placement. While the vast majority of patients do not restenose, resistive index and peak systolic velocity differed significantly between the 2 groups and may be prognostic surveillance markers for the development of restenosis.

Diagnostic, treatment, and surgical imaging in epilepsy.

Dedicated epilepsy centers are growing in hospitals throughout the USA and abroad, with a continuously increasing role of imaging in multidisciplinary meetings. Imaging is paramount in diagnosis, treatment, and surgical decision-making in lesional and nonlesional epileptic disease. Besides being up-to-date with technical developments in imaging that may make an impact in patient care, familiarity with clinical and surgical aspects of epilepsy is fundamental to better understanding of patient management. The present article intends to revisit diagnostic, therapeutic, and surgical imaging in epilepsy. Finally, with the increase in frequency of epilepsy management-related procedures and their hardware, MRI safety issues are discussed.

Magnetic Resonance Imaging of Pediatric Neurologic Emergencies.

Although computed tomography is often the first line of imaging in the emergency setting, magnetic resonance imaging (MRI) is of increasing importance in the evaluation of central nervous system emergencies in the pediatric population. As such, it is necessary to understand the indications for which MRI may be necessary. This article reviews the unique pathophysiologic entities affecting the pediatric population and the associated MRI findings. Specifically, utility of emergent MRI and characteristic appearances of traumatic brain injury, traumatic spinal injury, nonaccidental trauma, arterial ischemic stroke, cerebral sinovenous thrombosis, stroke mimics, and central nervous system infections are described.

Ultrasound findings after endovascular stent deployment in transplant liver hepatic artery stenosis.

OBJECTIVE: Endovascular stenting is a safe, effective treatment of hepatic artery stenosis after liver transplant, but no detailed evaluation has been completed of changes in ultrasound monitoring parameters after stenting. This study aims to improve poststenting surveillance by delineating the expected postoperative findings. MATERIALS AND METHODS: Thirty-one stent procedures were performed at our institution for hepatic artery stenosis after liver transplant between October 2010 and October 2012. Of these, 28 (90%) were technically successful, of which 23 met the minimum follow-up time (76 days, defined by the earliest diagnosed restenosis). These patients were followed with serial ultrasound, per the following schedule: within 1 week of stenting, 3 months after stenting, 6 months after stenting, and every 6 months thereafter; additional, unscheduled examinations were frequently performed when indicated on the basis of deterioration of clinical and laboratory status. Follow-up examinations (mean, 268 days total follow-up) were compared with prestenting examinations to evaluate changes in peak systolic velocity (PSV), resistive index (RI), and tardus-parvus waveforms. Data were analyzed to determine a normal range for postprocedure values and time course of change in values. RESULTS: Of the 23 patients, six experienced restenosis. In all patients, mean PSV decreased by 124 cm/s, and mean RI increased by 0.13 within 48 hours after stenting. PSV differed between patency and restenosis groups only at more than 90 days after stenting (mean PSV, 234 and 400 cm/s, respectively), with PSV above 300 cm/s serving as a high-sensitivity threshold for the determination of restenosis. Prestenting RI of below 0.40 had a strong correlation with restenosis. Poststenting RI differed between patency and restenosis groups only at more than 48 hours after stenting, with RI of below 0.55 having a strong correlation with restenosis. Tardus-parvus waveform resolution was often delayed well beyond 48 hours after stenting, and time to tardus-parvus waveform resolution had no correlation with patency or restenosis. CONCLUSION: Ultrasound is convenient and useful to follow stents in hepatic artery stenosis after liver transplant. Prestenting hemodynamics can have value in predicting restenosis. Diagnosis of restenosis can be made with RI and PSV, whereas resolution time of tardus-parvus waveform is of less concern. These parameters can guide which patients require closer monitoring and aggressive treatment.