Neuroendocrine carcinoma of the urinary bladder: a retrospective study of CT findings.

PURPOSE: The purpose of this study was to evaluate the radiographic features of neuroendocrine carcinoma of the urinary bladder (NECB) on CT and to review the literature regarding carcinogenesis, treatment, and prognosis. METHODS: The presenting CT of patients with pathology-proven NECB were retrospectively reviewed for features including size and appearance of the bladder mass, the presence of hydronephrosis, bladder wall thickening, invasion of perivesical fat, lymph nodes, and distant metastasis. Follow-up imaging and the medical record were reviewed to determine patient treatment and overall survival. RESULTS: Sixteen patients (13 males, 3 females) were diagnosed with NECB with a mean age of 75.5 years (range 48-90). The characteristic CT appearance was a large polypoid bladder mass (average size 4.9 cm). Extension into the perivesical fat, adjacent organ involvement, and distant metastases were common. CONCLUSION: NECB is an aggressive primary neoplasm of the bladder that presents on CT as a large bladder mass with local extension into the perivesical fat, involvement of adjacent organs, and metastasis.

Complications of renal transplantation.

Continued improvements in graft survival have led to widespread acceptance of renal transplantation as the preferred treatment for the majority of patients with end-stage renal disease. The long-term care of these patients is often provided away from transplantation centers. This article presents both the clinical and imaging features of renal transplantation complications and their interventional management. Urologic and vascular complications may occur. Vascular complications include renal artery stenosis and renal artery and renal vein thrombosis. Ultrasound can accurately depict and characterize many of the potential complications of renal transplantation and increasingly magnetic resonance imaging also facilitates this role. In addition, interventional radiologic techniques allow nonsurgical treatment.

CT features of renal infarction.

PURPOSE: To demonstrate the different patterns of renal infarction to avoid pitfalls. To present 'flip-flop enhancement' pattern in renal infarction. MATERIALS AND METHODS: Retrospective review of a total of 41 renal infarction in 37 patients were done. These patients underwent initial CT and the diagnosis of renal infarction was confirmed with either follow up CT or at surgery. RESULTS: Twenty-three patients had wedge-shaped focal infarcts, nine patients had global and five patients had multifocal infarcts of the kidneys. Cortical rim sign was seen predominantly with global infarcts. In five patients, a 'flip-flop enhancement' pattern was observed. In two patients, planned renal biopsies due to tumefactive renal lesions were cancelled because of 'flip-flop enhancement' pattern on follow up CTs. CONCLUSION: Although most of our cases were straightforward for the diagnosis of renal infarction, cases with tumefactive lesions and global infarctions without the well-known cortical rim sign were particularly challenging. We describe a new sign, flip-flop enhancement pattern, which we believe solidified the diagnosis of renal infarction in five of our cases. The authors recommend further investigations for association of flip-flop enhancement and renal infarction.

Clinical outcome of active extravasation in splenic trauma.

The purpose of this study was to determine the necessity for splenectomy in patients with active extravasation on contrast enhanced CT secondary to splenic trauma. We reviewed cases of splenic injury and classified these according to the American Association for the Surgery of Trauma (AAST) grading scale. The presence of active extravasation and associated injuries was assessed. Chart review was then performed to determine age, sex, mechanism of injury, indications for splenectomy, and clinical outcome. Of 82 cases evaluated, 12 grade I, 15 grade II, 30 grade III, 17 grade IV, and 8 grade V injuries were present. Eighteen patients were actively extravasating. Of extravasating patients, 13 eventually underwent open splenectomy or embolization and five (27.8%) were managed expectantly with success. Of grade IV injuries, 9/17 showed active extravasation, of which six underwent splenectomy. Of grade V injuries, 3/8 showed active extravasation, and all three underwent intervention. Splenectomy may not be necessary in appropriately chosen patients with active extravasation from the spleen in blunt abdominal trauma.