BWH emergency radiology--surgical correlation: small-bowel GI stromal tumor perforation.

We present the radiological and intraoperative correlation of a large necrotic gastrointestinal stromal tumor (GIST) with features of a tumor-bowel fistula and perforation in a 49-year-old woman presenting to the emergency department with a 4-day history of worsening abdominal pain, vomiting, and diarrhea. The patient underwent urgent exploratory laparotomy for partial resection of the small bowel, with primary anastomosis. The purpose of this article is to emphasize the importance for emergency radiologists to be familiar with this entity and its possible complications to help guide the surgeons in the patient's management.

The role of demyelination in neuromyelitis optica damage: diffusion-tensor MR imaging study.

PURPOSE: To test the hypothesis that white matter damage in neuromyelitis optica (NMO) is more extensive than previously described and likely includes involvement of normal-appearing white matter and to explore by using diffusion-tensor (DT) imaging whether white matter lesions are not only related to wallerian degeneration but are also caused by demyelination. MATERIALS AND METHODS: Seventeen patients with NMO (mean age, 45 years; 14 women) were compared with 17 sex- and age-matched control subjects. The institutional review board approved the study, and all subjects gave written informed consent. In addition to conventional magnetic resonance imaging sequences, DT imaging was performed along 30 noncollinear directions by using a 1.5-T imager. For tract-based spatial statistics (TBSS) analysis, the white matter skeleton was created, and a permutation-based inference with 5000 permutations with a threshold of P less than .05 to enable the identification of abnormalities in fractional anisotropy (FA), radial diffusivity (RD), and axial diffusivity (AD) was used. Partial correlation was applied to identify whether the number of clinical relapses and disease duration were correlated with all TBSS parameters. RESULTS: TBSS showed multiple areas with significant FA decrease in patients with NMO, mainly located in the corona radiata, uncinate fasciculus, corpus callosum, optic radiation, internal and external capsules, and cerebral peduncles. The mean FA, RD, and AD in the abnormal voxels located on the corpus callosum were, respectively, 0.69 ± 0.03 (standard deviation), 0.39 × 10(23) mm(2)/sec ± 0.04, and 1.53 × 10(23) mm(2)/sec ± 0.04 in patients with NMO compared with 0.75 ± 0.02, 0.33 × 10(23) mm(2)/sec ± 0.03, and 1.57 × 10(23) mm(2)/sec ± 0.04 in control subjects (P < .0001, P < .0001, and P = .007, respectively). There was a highly significant inverse correlation between FA and RD (r = 20.976, P < .0001). CONCLUSION: The use of TBSS allowed the identification of extensive white matter damage in patients with NMO. Multiple white matter tracts were involved, including the pyramidal tract, optic radiation, and corpus callosum, likely related to both demyelination and wallerian degeneration.

Split-bolus single scan CTA for evaluation of mesenteric ischemia.

PURPOSE: To evaluate split-bolus single scan CTA protocol for evaluation of acute mesenteric ischemia. MATERIALS AND METHODS: In this HIPAA-compliant IRB-approved study, consecutive patients evaluated for mesenteric ischemia between 11/2015 and 10/2016 were included. Patients scanned prior to 4/2016 were scanned with multiphasic CTA protocol and after with split-bolus single scan CTA. Objective and subjective evaluation was performed by three board-certified readers. Findings were correlated to composite clinical reference outcome. RESULTS: Eighty patients were included: 40 with split-bolus and 40 with multiphasic CTA protocol with similar age (60.3 ± 16.2 years vs. 64.7 ± 17.0 years, p = 0.19) and BMI (28.0 ± 6.7 vs. 27.0 ± 8.7, p = 0.56). SMA attenuation was higher in multiphasic protocol compared to split-bolus protocol (336.5 ± 97.5 HU vs. 258.0 ± 67.3 HU, p < 0.001) with similar SMV attenuation (multiphasic 213.7 ± 58.4 HU vs. split-bolus 194.2 ± 52.2 HU, p = 0.14). Optimal phase of bowel, liver, and spleen enhancement was seen in similar high proportion (94-99%) in both protocols. There were 8/40 (20%) positive cases of mesenteric ischemia in each group. There was no difference in the diagnostic confidence of the readers for evaluation of the mesenteric vessels and bowel ischemia. There were no missed cases of mesenteric ischemia in either group. Mean effective dose was 42% lower in the split-bolus group, p < 0.001. There was a higher number of axial images to review in multiphasic protocol compared to split-bolus protocol (437.9 ± 48.7 vs. 263.5 ± 31.2, p < 0.001). CONCLUSIONS: The split-bolus protocol for evaluation of mesenteric ischemia is clinically feasible with confident and accurate diagnostic ability, while reducing number of images and decreasing radiation exposure to the patient.

Hypervascular mediastinal masses: action points for radiologists.

Hypervascular mediastinal masses are a distinct group of rare diseases that include a subset of benign and malignant entities. Characteristic features and known association with syndromes and genetic mutations assist in achieving a diagnosis. Imaging allows an understanding of the vascularity of the lesion and should alert the radiologist and clinician to potential hemorrhagic complications and avoid percutaneous CT guided biopsies. In such cases, pre-procedure embolization and surgical biopsy maybe considered for better control of post procedure hemorrhage. The purpose of this article is to describe and illustrate the clinical features and radiologic spectrum of hypervascular mediastinal masses, and discuss the associated clinical and genetic syndromes. We will present an imaging algorithm to determine further evaluation and subsequently guide treatment.

Teratoma with malignant transformation: report of three cases and review of the literature.

Teratoma with malignant transformation is an uncommon, very aggressive germ cell tumor that has undergone transformation of a somatic teratomatous component to a histologic type identical to a somatic malignancy. We review the clinical presentation, imaging appearances, and prognosis of this entity and highlight its aggressive behavior by reporting on three patients with metastatic testicular nonseminomatous germ cell tumor with histologically proved malignant transformation.

Peritoneal lymphomatosis: CT and PET/CT findings and how to differentiate between carcinomatosis and sarcomatosis.

Peritoneal lymphomatosis is a rare manifestation of lymphoma, seen most frequently with non-Hodgkin lymphoma, and it is important to be familiar with this condition, because early diagnosis directly affects the management of patients. This review illustrates the spectrum of imaging findings in peritoneal lymphomatosis, highlighting the use of positron emission tomography/computed tomography, showing common and uncommon subtypes of lymphoma associated with this entity, and how to differentiate it from peritoneal carcinomatosis and peritoneal sarcomatosis.

Semi-invasive pulmonary aspergillosis in an immunosuppressed patient: a case report.

BACKGROUND: The authors present the high-resolution computed tomography findings of an immunosuppressed patient with semi-invasive pulmonary aspergillosis. CASE PRESENTATION: The main finding consisted of irregular, thick-walled cavity in the right upper lobe and a mass with soft-tissue attenuation within it and thickening of adjacent pleura. Additional findings were bronchial wall thickening associated with a 'tree-in-bud' pattern. Following the clinical, laboratorial and imaging criteria, the diagnosis of semi-invasive pulmonary aspergillosis was defined and antifungical treatment was introduced. CONCLUSION: The patient responded well to the treatment with improvement in his systemic symptoms and regression of the pulmonary lesions.