Biomedical subjects
Publications and source records attributed to W F Bennett.
Castleman disease, or angiofollicullar hyperplasia, is a rare cause of lymph node enlargement. This most commonly occurs within the thorax, although rare extrathoracic presentations have been described. Only two cases with hepatic localization have been reported. We present a case of Castleman disease within the porta hepatis masquerading as a hepatic neoplasm.
Explore the source record for details and available documents.
Plain radiography and CT features of a posterior mediastinal teratoma are presented. Computed tomography confirmed the posterior mediastinal origin of this mass, added information about its content, and revealed apparent sparing of the surrounding structures, thus playing an important role in surgical planning.
A case of adenocarcinoma of the fallopian tube that presented as a small mucosal papillary growth in a large, otherwise noncomplicated hydrosalpinx is reported. Computed tomography clearly delineated the mucosal tumor and characteristic unilateral tubular shaped adnexal mass of the hydrosalpinx which was easily distinguishable from ovarian cystic masses.
In 15 patients who were to undergo resection of hepatic metastases, three-dimensional (3D) images of the liver were rendered from axial T2-weighted MR images by a dedicated 3D workstation. This report assesses the utility of these images in preoperative planning and intraoperative guidance. In three patients, the preoperative 3D images convinced the surgeon of resectability. All patients had laparotomies and in 12 patients, in whom the liver lesions were evaluated, there was good to excellent spatial correlation. Intraoperatively, the 3D images aided the surgeon by allowing early detection of unresectability, by showing relationships of lesions to major vessels, and by directing the surgeon to lesions otherwise difficult to find. In two patients, the original MR images failed to show multiple small lesions, thus limiting the usefulness of the 3D images.
Acute mesenteric vein thrombosis is a rare complication of appendicitis. In this report we describe the clinical association of these entities and emphasize how early diagnosis by CT can expedite treatment.
OBJECTIVE: Our goal was to compare the relative values of MRI vs. CT in diagnosing recurrent rectosigmoid cancer. MATERIALS AND METHODS: We conducted a retrospective review of 18 patients who had surgical resection of primary rectosigmoid carcinoma and suspected recurrence. They were studied with CT and MR and followed for up to 4 years. RESULTS: At the time of the initial imaging, 10 patients had recurrent tumor and 4 of the remaining 8 patients later demonstrated local recurrence. Magnetic resonance demonstrated 91% sensitivity, 100% specificity, a positive predictive value (PPV) of 100%, and a negative predictive value (NPV) of 89% with a 95% accuracy. Computed tomography demonstrated a sensitivity of 82% and a specificity of 50% with a PPV of 69% and an NPV of 67% with an accuracy of 68%. In three cases interpreted on CT as presacral masses, all were shown on MR to represent displaced but normal pelvic structures. In four cases MR revealed tumor involving the sacrum and sacral nerves not apparent on CT. CONCLUSION: Magnetic resonance showed superior sensitivity, specificity, and accuracy to CT and better definition of the extent of tumor.
Mangafodipir trisodium (Teslascan), a hepatobiliary contrast agent, has the potential of providing functional biliary imaging similar to hepatobiliary scintigraphy. To our knowledge. the potential role of this biliary contrast agent in the detection of bile duct leaks has not been reported. In this case report, we report the first case of a bile duct leak diagnosed with enhanced MRI with mangafodipir trisodium in a patient following laparoscopic cholecystectomy. Our case illustrates that functional MR cholangiography images can be successfully acquired by using a post-mangafodipir fat-suppressed GRE technique and that bile duct leaks can be detected.
PURPOSE: In this manuscript, we present our initial experience with MRI of the abdomen at 8 T of canine subjects both alive and dead. Our hypothesis is that abdominal imaging at 8 T should be possible and should demonstrate unique information. To our knowledge, this is the first description of imaging characteristics of the abdomen at such field strengths using a human MR scanner. METHOD: An 8 T, 80 cm magnet housed in our department since 1998 was used for our study. GRE and rapid acquisition by relaxation enhancement (RARE) pulse sequences were selected to give reasonable slice profiles with relatively low power. Three dogs were imaged alive and after being killed. RESULTS: Our initial results show excellent signal-to-noise ratio and good RF penetration. Structures in the center of the abdomen were well visualized. Homogeneous signal was noted throughout each image without dielectric resonance artifact. Magnetic susceptibility artifacts were most severe on the GRE sequences. On the GRE sequences, the images appeared relatively T2 weighted. Signal voids were seen due to gas in the lung and bowel and susceptibility artifact at subcutaneous fat-muscle boundaries. The liver and spleen showed similar signal intensity, hypointense to subcutaneous muscle at low TE values. There was little internal anatomy of the liver or spleen visible except for the vessels. The kidney, in contrast, demonstrated very good internal structure with visualization of the cortex and medulla. Linear signal voids were depicted in the expected location of normal renal vascular anatomy on the GRE sequences. On the RARE sequences, the images also appeared T2 weighted. Magnetic susceptibility artifacts at subcutaneous fat-muscle boundaries were absent. Signal voids were noted in vessels with blood flow and gas. The liver and spleen were of similar signal intensity and slightly hypointense to muscle. The kidney and pancreas were of higher signal intensity than liver and subcutaneous muscle. The gallbladder wall demonstrated a striated pattern of two layers, with an inner hypointense and an outer hyperintense layer on the RARE sequence. The gastric wall demonstrated a striated pattern of five layers on the RARE sequence. CONCLUSION: Images of the dog abdomen with the world's first ultra high field 8 T magnet show robust image quality and excellent spatial resolution. Image contrast is greatest on the RARE sequence, and susceptibility artifact is strongest on the GRE sequence.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.