A Rare Red Herring: Intrahepatic Splenosis Masquerading as Hepatocellular Carcinoma.

Splenosis is defined as viable splenic tissue that is autotransplanted into other compartments in the body. Intrahepatic splenosis is a rare diagnosis that can be difficult for clinicians to identify. The most common causes of splenosis include abdominal trauma and splenectomy. While most patients with intrahepatic splenosis are asymptomatic, in the presence of risk factors of hepatocellular carcinoma, it is paramount to rule out malignancy. In this report, we present a patient with imaging findings concerning for hepatocellular carcinoma, ultimately diagnosed with percutaneous biopsy and technetium-99m-tagged heat-damaged red blood cell scintigraphy-proven intrahepatic splenosis.

Biliary excretion of gadobenate dimeglumine causing degradation of magnetic resonance cholangiopancreatography (MRCP).

PURPOSE: To assess the effect of gadobenate dimeglumine on magnetic resonance cholangiopancreatography (MRCP) and determine an appropriate time frame for performing MRCP sequences. MATERIALS AND METHODS: 2D MRCP sequences obtained after intravenous administration of gadobenate dimeglumine or gadobutrol over 14 months were reviewed retrospectively in randomized order by five abdominal radiologists, using a 3-point scale to rate biliary and pancreatic duct clarity (1 = no-, 2 = limited-, 3 = good visualization). Intraclass correlation coefficients were computed and mean scores were compared for both agents. For gadobenate dimeglumine exams, time delays between arterial phase and MRCP acquisition times were analyzed concerning duct clarity. For gadobutrol, only exams with delays ≥ 15 min were included. RESULTS: 134 exams (107 gadobenate dimeglumine, 27 gadobutrol) were included. Moderate reliability for pancreatic duct visualization and excellent reliability for visualization of intrahepatic bile ducts and upper and lower extrahepatic bile ducts were noted. No difference in mean scores was noted for pancreatic duct visualization (p = 0.66). Bile duct segment scores were lower with gadobenate dimeglumine (mean: 2.1-2.6) compared with gadobutrol (mean: 2.8-2.9) (p ≤ 0.006). For gadobenate dimeglumine, visualization scores varied depending on the delay between the arterial phase and MRCP acquisition (p ≤ 0.047). Good visualization for all bile duct segments was noted with delays of 7.2-9.4 min (95% confidence interval; mean 8.3 min). CONCLUSION: Bile duct clarity degraded on MRCP images with an increasing delay following gadobenate dimeglumine injection. 2D MRCP, thus, should be performed within 7.2 min after obtaining the arterial phase sequence to ensure good visualization of the entire biliary system.

The Increasing Use of Emergency Department Imaging in the United States: Is It Appropriate?

OBJECTIVE. The purpose of this study was to study trends in utilization of imaging in emergency departments (ED) in relation to trends in ED visits and the specialties of the interpreting physicians. MATERIALS AND METHODS. This study was conducted with Medicare Part B Physician/Supplier Procedure Summary Master Files for 2004-2016 and Health Care Cost and Utilization Project (HCUP) data from 2006 to 2014. Yearly utilization was calculated per 1000 Medicare beneficiaries for different noninvasive imaging modalities performed during ED visits, and the specialties of the physicians making the interpretations were recorded. The number of ED visits by Medicare patients was obtained from the HCUP. RESULTS. The number of ED visits by Medicare fee-for-service patients increased 8.0% (from 20.0 million in 2006 to 21.6 million in 2014), and the total number of associated ED imaging examinations increased 38.4% (14.6 million to 20.2 million). The number of imaging examinations per ED visit was 0.73 in 2006, increasing to 0.94 by 2014. Utilization trends per 1000 Medicare fee-for-service enrollees in the ED for the major modalities were as follows: CT +153.0% (77.8 in 2004 to 196.7 in 2016), noncardiac ultrasound +134% (11.2 in 2004 to 26.2 in 2016), and radiography +30% (259 in 2004 to 336 in 2016). Utilization of MRI and nuclear medicine was very low. In 2016, radiologists interpreted 99.5% (CT), 99.2% (MRI), 98.0% (radiography), 87.6% (ultrasound), and 94.5% (nuclear medicine) of imaging examinations. CONCLUSION. Utilization of imaging in EDs is increasing not only in the Medicare population but also per ED visit. Radiologists strongly predominate in interpreting examinations in all modalities.

The utility of whole spine survey MRI in blunt trauma patients sustaining single level or contiguous spinal fractures.

PURPOSE: To determine the utility of obtaining whole-spine survey MRI after a whole-spine CT diagnoses single level or contiguous fractures. METHODS: A retrospective search from 2015 to 2017 was performed using an institutional PACS database for consecutive patients who sustained spinal fractures from blunt injury. Only patients who received whole-spine CT followed by whole-spine MRI were included in the study. All cases had sagittal T2-weighted and Short TI (Tau) inversion recovery (STIR) imaging of the entire spine with additional T1 and T2-weighted axial imaging covering the known injury. Reports from the whole-spine CTs were compared to the reports of the whole-spine MRI to determine if additional bony and soft tissue injury were identified on subsequent MRI. RESULTS: A total of 156 patients met the inclusion criteria, with an average age of 59.5 ± 20.6 years. Twenty-nine patients (18.5%) had a whole-spine MRI that demonstrated an additional bony ± soft tissue injury. A 95.1% of the additional injuries were osseous contusions or vertebral body compression fractures without significant loss of height. The distance between the original injury on CT and the additional injury on MR ranged from 1 to 13 vertebrae. A 82.8% of the additional injuries occurred within 1 to 8 vertebrae levels of the primary injury and most commonly in the thoracic spine. CONCLUSIONS: Most additional bony injuries detected on MRI are bone contusions and mild compression fractures, which are unlikely to alter management. However, if screening MRI is performed for additional bony injuries, we posit that a targeted regional spinal MRI is adequate.

Intraosseous hemangioblastoma of the cervical spine: case report.

A 69-year-old woman presented with bilateral upper-extremity radiculopathy and neck pain after a mechanical fall. Admission CT and MRI of the cervical spine demonstrated a pathological C-4 fracture. Subsequent malignancy workup was negative. A CT-guided biopsy of the lesion showed intraosseous hemangioblastoma. Hemangioblastoma is a highly vascular, slow-growing tumor of the CNS; intraosseous location of this tumor is extremely rare. The authors review the diversity of its presentation and the treatment techniques of this rare tumor in an extremely rare location.

Emergency radiology fellowship training in the USA: a web-based survey of academic programs.

Interest in emergency radiology as a distinct subspecialty within radiology continues to rise in the USA and globally. While acute care imaging has been performed since the earliest days of the specialty, fellowship training in emergency radiology is a relatively new phenomenon. The purpose of this study was to examine the current status of emergency radiology training in the USA, using data derived from the official websites of US residency training programs. The most current list of radiology residency programs participating in the 2017 match was obtained from the official Electronic Residency Application Service (ERAS) website. The total number of emergency radiology fellowships was recorded after visiting available websites of each academic radiology program. The total number of subspecialty fellowships offered by each academic radiology program was also recorded. There were 12 confirmed emergency radiology fellowships offered in the USA for a combined total of 22 fellowship positions. Eleven programs were 1 year in duration, with one program offering a one- or two-year option. One hundred eight of the 174 (approximately 62 %) surveyed academic radiology programs offered at least one subspecialty fellowship. Emergency radiology fellowships are on the rise, paralleling the growth of emergency radiology as a distinct subspecialty within radiology.

Imaging of ocular melanoma metastasis.

Ocular melanoma is the most common adult primary intraocular tumour. Although <1% of patients have metastatic disease at the time of initial diagnosis, most will develop metastasis at varying lengths of time. Metastasis surveillance is therefore critical in the follow-up of patients with ocular melanoma. Liver is the most common site of metastasis and prognosis is based on the treatment of liver metastasis. Hence, imaging of liver metastasis is vital. MRI is the most specific modality for imaging liver metastasis and is at least as sensitive as CT. Extrahepatic metastasis such as retroperitoneal nodules and bone metastases are also better evaluated on MRI. Gadolinium-based contrast agents are extremely helpful for detecting liver lesions. In particular, newer hepatobiliary contrast agents which offer an additional hepatobiliary phase of excretion help in the detection of even tiny liver metastases. Diffusion-weighted imaging is helpful when an i.v. contrast cannot be administered. Treated lesions are also better evaluated with MRI. CT is useful for evaluating lung nodules, large liver metastasis or in patients in whom MRI is medically contraindicated. The disadvantage lies in its inability to detect small liver metastasis and the radiation dose involved. The lesions treated with iodized oil as part of chemoembolization procedures can be followed on CT. Ultrasound can be used only for detecting hepatic metastases. However, it is heavily operator dependent, technically challenging and time consuming especially in patients who are large. Extrahepatic metastasis cannot be seen on ultrasound. Its utility is primarily for the biopsy of liver lesions. Positron emission tomography (PET)-CT can detect lung nodules and large liver lesions but is insensitive to small liver lesions. Moreover, the high radiation dose is a major disadvantage.

Yield of Preoperative Whole-body CT in Patients Presenting with Single Brain Malignancy:: Experience at a Tertiary-care Center.

RATIONALE AND OBJECTIVES: Single brain malignancy (SBM) often poses a diagnostic dilemma, with differential diagnosis of primary brain malignancy (PBM) versus metastasis commonly rendered. This study assesses the yield of preoperative computed tomography (CT) of the chest, abdomen, and pelvis (CTCAP) in patients with SBM. MATERIALS AND METHODS: Institutional review board (IRB)-approved retrospective review of the imaging database at a tertiary-care center was performed for patients with magnetic resonance findings compatible with a diagnosis of SBM. Demographic information, lesion characteristics (location and size), and pathology were recorded. Findings of CTCAP for metastatic workup prior to SBM excisional biopsy were also documented, if performed. RESULTS: Eighty-six of 92 patients with new diagnosis of SBM on MR imaging had subsequent lesion resection and pathology consistent with malignancy. PBM accounted for 51 cases (59%) and metastasis accounted for 35 cases (41%). When stratified by age group, PBM was more common in patients <50 years old (15 of 18 (83%)), whereas similar rates of PBM and metastatic disease were identified in older patients. When stratified by lesion size, PBM was more common in tumors ≥40 mm (25 of 31 (81%)), whereas similar rates of PBM and metastatic disease were identified in smaller lesions. Lung cancer was the most common CTCAP and pathology-confirmed source of metastatic SBM (68% and 66%, respectively). CONCLUSIONS: The yield of preoperative CTCAP can be increased by targeting patients older than 50 years of age with SBMs smaller than 40 mm in size.