Tatsuro Fukuya

Efficacy of Helical Ct in T-staging of Gastric Cancer

PURPOSE The purpose of this study was to evaluate the performance of helical CT in preoperative T-staging in patients with gastric cancer. METHOD A total of 71 patients with an established diagnosis of gastric cancer [75 lesions, 46 early (T1) and 29 advanced (T2 or more) cancers] were evaluated with helical CT. Helical CT was performed with 5-mm slice thickness at 5-mm/s table incrementation. Using the volumetric data by helical scanning, axial CT images (5-mm slice thickness at 5-mm intervals) and multiplanar reconstruction (MPR) images were obtained. CT findings were compared with histopathologic studies of the resected specimen. RESULTS Sensitivity of helical CT for gastric cancer was 26% (12 of 46) for early and 100% (29 of 29) for advanced cancer. Three lesions were misdiagnosed as gastric cancer by helical CT. Histopathologically, all early gastric cancers detected by helical CT were either polypoid or elevated types or showed massive invasion of the submucosal layer. The differentiation between T1 cancer with massive submucosal invasion and advanced cancer was difficult. The differentiation between T2 and T3 cancer was possible in 73% (19 of 26) and between T1/T2 and T3/T4 (extraserosal invasion) in 83% (34 of 41). Overall T-staging was correct in 66% (27 of 41). MPR images improved the detection rate (three lesions) or increased confidence in T-staging (eight lesions) over axial CT images. CONCLUSION When helical CT detected gastric cancer that was not a polypoid or elevated type with underlying normal-appearing gastric wall, it was either T1 cancer with massive invasion of the cancer cells into the submucosal layer or advanced cancer. However, differentiation between these two stages was difficult on CT. Diagnosis of serosal invasion was not markedly improved by helical CT. MPR images increased confidence in the staging of certain gastric cancers, such as those in locations where CT images are susceptible to partial volume averaging effects.

Computed tomographic findings of Bellini duct carcinoma of the kidney.

OBJECTIVE To analyze CT findings of Bellini duct carcinoma, a rare variant of renal cell carcinoma. MATERIALS AND METHODS The CT findings of five cases of Bellini duct carcinoma were reviewed and the findings were recorded. RESULTS In all cases the affected kidneys maintained the normal outer contours. In four cases the renal masses protruded into the central sinuses. Contrast enhancement was minimal in four cases. CONCLUSION Bellini duct carcinoma should be suspected in cases with these CT findings.

Inflammatory pseudotumors of the spleen: CT and MRI findings

OBJECTIVE Our goal was to elucidate the CT and MRI findings of inflammatory pseudotumors of the spleen. METHODS The CT and MRI findings of three patients with inflammatory pseudotumors of the spleen were reviewed and compared with the pathologic findings. RESULTS On the early phase of CT, the masses were hypodense to the normal spleen, and on the delayed phase, they demonstrated delayed enhancement. On T1-weighted MR images, the masses were isointense to the normal spleen, and on T2-weighted images, the masses had heterogeneous low signal intensities. After administration of Gd-DTPA, the masses showed delayed enhancement. CONCLUSION Inflammatory pseudotumors of the spleen were characterized by low signal intensity on T2-weighted MR images and delayed enhancement after contrast material administration on CT and MRI. The fibrous stroma may contribute to these unusual findings.

CT and MR findings of brain aspergillosis.

CT and MR findings of a case of brain aspergillosis with histopathologic correlation are reported. On both CT and MR images, there were multiple lesions in the corticomedullary junction (CMJ) that appeared to disrupt the cortical sulci and that were not enhanced by intravenous contrast material. In most of these lesions, there were centrally located structures that were enhanced by intravenous contrast material and that appeared to be continuous from markedly enhanced adjacent dilated cortical vessels. Histopathologic examination of the autopsy specimen showed multiple hemorrhagic infarcts in the CMJ with remaining dilated cortical vessels that had been thrombosed by aspergillus hyphae.

Predictors of microscopic portal vein invasion by hepatocellular carcinoma: Measurement of portal perfusion defect area ratio

Objective:  Microscopic portal vein invasion (PVI) by cancer cells is a poor prognostic factor after hepatic resection for hepatocellular carcinoma (HCC). The aim of this study is to predict PVI preoperatively in patients with HCC.

Postoperative MRI evaluation of anorectal malformations with clinical correlation

Sixteen postoperative patients with anorectal malformation were evaluated by MRI, and the results compared with the clinical assessment. Patients were classified into three groups — good (group 1,n=10), fair (group 2,n=3) and poor (group 3,n=3) — on the basis of Kellys clinical score of incontinence. The degree of development of the puborectalis and external sphincter muscles and the levator hammock was evaluated on MRI in comparison with patients without anorectal disease. The proportions of fair or poor development of the muscles were 37% in group 1,22% in group 2 and 67% in group 3. Although fair or poor development of the muscles was seen more frequently in group 3, there was no statistically significant difference between groups. However, poorly developed muscles were seen only in patients with fair or poor clinical scores. The difference in the anorectal angle measured on sagittal MRI images between patients in group 1 and groups 2 or 3 was significant. Our study indicates that MRI evaluation based solely on muscle development can be misleading, and measurement of the anorectal angle should be included in the MRI evaluation.

Incidentally detected lesions on contrast-enhanced MR imaging in candidates for breast-conserving therapy: Correlation between MR findings and histological diagnosis

To investigate the correlation between MR findings and the histological diagnosis of incidentally detected lesions in candidates for breast‐conserving therapy.

MRI of primary lymphoma of the liver

Objective The MR findings in two cases of primary lymphoma of the liver (PLL) are presented. Materials and Methods MR of two cases of primary lymphoma of the liver were reviewed and its features were estimated. Results Both cases showed a solitary large liver mass. On T1-weighted imaging the tumor was isointense in one and homogeneously hypointense to the liver parenchyma in the other. On T2-weighted imaging both tumors were homogeneously hyperintense. In one case the margin of the tumor was poorly defined, and portal branches were identified within the tumor, an unusual finding in other liver neoplasms. Conclusion In patients with liver masses with homogeneous intensity on MR but without liver dysfunction and other malignancies, PLL should be included in the differential diagnosis.

Plasmacytoma of the pancreatic head

Plasmacytomas of the pancreas are extremely rare. This is a report of a patient with plasmacytoma of the head of the pancreas who also had an extramedullary plasmacytoma of the epipharynx 19 months earlier. Computed tomographic (CT) scans revealed a multilobular homogeneous mass in the pancreas. Endoscopic biopsy of adjacent polypoid lesions in the duodenum allowed confirmation of the diagnosis.

Treatment of hepatic encephalopathy by retrograde transcaval coil embolization of an ileal vein-to-right gonadal vein portosystemic shunt

A 43-year-old non-cirrhotic woman suffered from encephalopathy caused by an extrahepatic portosystemic shunt between the ileal vein and inferior vena cava via the right gonadal vein. Percutaneous transcatheter embolization with stainless steel coils was performed by the retrograde systemic venous approach. Encephalopathy improved dramatically.