Transplantation for type 1 diabetes: radiologist's primer on islet, pancreas and pancreas-kidney transplantation imaging.

Whole-organ pancreas, pancreatic-kidney and islet transplantation are surgical therapeutic options for the treatment of type 1 diabetes. They can enable effective glycemic control, improve quality of life and delay/reduce the secondary complications of type 1 diabetes mellitus. Radiologists are integral members of the multidisciplinary transplantation team involved in these procedures, with multimodality imaging serving as the mainstay for early recognition and management of transplant related complications. This review highlights the transplantation procedures available for patients with type 1 Diabetes Mellitus with a focus on the imaging appearance of transplantation-related complications.

Acute Acalculous Cholecystitis in Hospitalized Patients With Hematologic Malignancies and Prognostic Importance of Gallbladder Ultrasound Findings.

OBJECTIVES: Patients with hematologic malignancies, especially those with acute disease or those receiving intense chemotherapy, are known to develop acute acalculous cholecystitis (AAC). The aim of this study was to evaluate the diagnostic and prognostic value of the established ultrasound (US) diagnostic criteria for AAC in patients with acute hematologic malignancies who were clinically suspected to have AAC. METHODS: We retrospectively studied the US findings of the gallbladder in patients with hematologic malignancies and correlated these findings with the duration of clinical symptoms, complications, and gallbladder-specific mortality. The major criteria were a 3.5-mm or thicker wall, pericholecystic fluid, intramural gas, and a sloughed mucosal membrane. The minor criteria were echogenic bile and hydrops (gallbladder distension > 4 cm). Ultrasound findings were considered positive if they included 2 major criteria or 1 major and 2 minor criteria. RESULTS: Ninety-four (25.5%) of 368 patients with hematologic malignancies had clinical signs of AAC during their acute phase of illness or during intense chemotherapy. Forty-three (45.7%) of these 94 patients had AAC-positive test results based on US criteria. The mean duration of symptoms was significantly longer (7.8 days) in this group than among the patients with negative test results (3.9 days; P < .001). Patients with positive test results had a higher rate of complications or mortality (20.9%) than those with negative test results (0%; P < .001). CONCLUSIONS: Symptomatic patients who meet the US criteria for the diagnosis of AAC have a poor prognosis. Other patients require a close follow-up US examination within 1 week to detect early progression.

Imaging features of rare mesenychmal liver tumours: beyond haemangiomas.

Tumours arising from mesenchymal tissue components such as vascular, fibrous and adipose tissue can manifest in the liver. Although histopathology is often necessary for definitive diagnosis, many of these lesions exhibit characteristic imaging features. The radiologist plays an important role in suggesting the diagnosis, which can direct appropriate immunohistochemical staining at histology. The aim of this review is to present clinical and imaging findings of a spectrum of mesenchymal liver tumours such as haemangioma, epithelioid haemangioendothelioma, lipoma, PEComa, angiosarcoma, inflammatory myofibroblastic tumour, solitary fibrous tumour, leiomyoma, leiomyosarcoma, Kaposi sarcoma, mesenchymal hamartoma, undifferentiated embryonal sarcoma, rhabdomyosarcoma and hepatic metastases. Knowledge of the characteristic features of these tumours will aid in guiding the radiologic diagnosis and appropriate patient management.

Radiation intensity (CTDIvol) and visibility of anatomical structures in head CT examinations.

The purpose of this study was to quantify how changing the amount of radiation used to perform routine head CT examinations (CTDIvol) affects visibility of key anatomical structures. Eight routine noncontrast head CT exams were selected from six CT scanners, each of which had a different CTDIvol setting (60 to 75 mGy). All exams were normal and two slices were selected for evaluation, one at the level of basal ganglia and the other at the fourth ventricle. Three experienced neuroradiologists evaluated the visibility of selected structures, including the putamen, caudate nucleus, thalamus, internal capsule, grey/white differentiation, and brainstem. Images were scored on a five-point scoring scheme (1, unacceptable, 3, satisfactory, and 5, excellent). Reader scores, averaged over the cases obtained from each scanner, were plotted as a function of the corresponding CTDIvol. Average scores for the fourth ventricle were 3.06 ± 0.83 and for the basal ganglia were 3.20 ± 0.86. No image received a score of 1. Two readers showed no clear trend of an increasing score with increasing CTDIvol. One reader showed a slight trend of increasing score with increasing CTDIvol, but the increase in score from a 25% increase in CTDIvol was a fraction of the standard deviation associated average scores. Collectively, results indicated that there were no clear improvements in visualizing neuroanatomy when CTDIvol increased from 60 to 75 mGy in routine head CT examinations. Our study showed no apparent benefit of using more than 60 mGy when performing routine noncontrast head CT examinations.