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Biomedical subjects

O Matsui

Publications and source records attributed to O Matsui.

At least 235 records · Page 13Linked to original sources
PubMedDate not supplied

Peribiliary cysts in liver cirrhosis: US, CT, and MR findings.

OBJECTIVE: We report the imaging features of hepatic peribiliary cysts (PC) and the course of their development on CT. MATERIALS AND METHODS: Both CT and US findings were correlated with histopathologic findings in two patients with PC at autopsy. Five patients with cysts around the portal vein on CT but without histologic correlation were also included in this study. In six patients the course of PC development was observed. RESULTS: In the two autopsy cases cystic dilatation of the peribiliary glands was confirmed. The cases showed continuous small cysts along the portal veins reflecting the periportal collar seen on CT and the abnormal MR signal intensity of the periportal area. Ultrasound (US) showed round or tubular anechoic lesions around the large portal tracts mimicking dilatation of the bile ducts. Clustered cysts and echogenic dots or bands around PC were also seen. In three of six cases the PCs gradually enlarged and increased in number. CONCLUSION: In patients with liver cirrhosis PCs can be demonstrated by CT, US, and MRI in the vicinity of the hepatic hilum. Peribiliary cysts enlarge gradually and must be differentiated from dilatation of bile ducts or edema of portal tracts.

Aged↗
PubMedDate not supplied

Focal hepatic fatty infiltration in the posterior edge of the medial segment associated with aberrant gastric venous drainage: CT, US, and MR findings.

OBJECTIVE: The purpose of this study is to demonstrate the relation between focal hepatic fatty infiltration and aberrant gastric venous drainage (AGVD) in the posterior edge of the medial segment (PEMS) of the liver. MATERIALS AND METHODS: We present two cases of focal hepatic fatty infiltration with AGVD in the PEMS and discuss their imaging features. RESULTS: In both cases the focal fatty infiltration areas were hyperechoic on sonography, hypodense on CT, and hyperintense on T1-weighted MRI. Computed tomography during arterial portography (CTAP) showed nodular perfusion defects corresponding to the areas in both cases, and early enhancement of the area was observed with dynamic MRI in one case. Although the findings on CTAP and dynamic MRI suggested a neoplastic nature for the lesions, focal fatty infiltration was confirmed with surgical resection in one case and with imaging follow-up in the other. Aberrant gastric venous drainage into the area was demonstrated on arteriography in both cases. CONCLUSION: The variation in blood supply caused by AGVD may play an important role in fatty metabolism in the PEMS of the liver and may influence imaging features.

Duodenum↗
PubMedDate not supplied

Imaging findings of mucinous type of cholangiocellular carcinoma.

OBJECTIVE: To demonstrate the imaging findings seen in two cases of mucinous type of cholangiocellular carcinoma of the liver. MATERIALS AND METHODS: The CT and MR findings of two patients with pathologically proven mucinous type of cholangiocellular carcinoma were analyzed. RESULTS: One of them showed calcification, both cases had no enhancing on the arterial dominant phase of dynamic CT, but showed enhancement in the periphery and internal septations on the equilibrium phase. The internal signal intensity was homogenous, and extremely hypo- and hyperintense on T1- and T2-weighted images, respectively. CONCLUSION: Imaging findings were unique reflecting the characteristic pathological features that cancer cell nests are suspended in a large mucinous lake, and the specific diagnosis was considered to be possible by the integrated imaging diagnosis.

Adenocarcinoma, Mucinous↗
PubMedDate not supplied

Dynamic MRI using a surface coil in chronic cholecystitis and gallbladder carcinoma: radiologic and histopathologic correlation.

PURPOSE: The purpose of this study was to determine whether dynamic MRI could differentiate gallbladder carcinoma from chronic cholecystitis. METHOD: The dynamic MR findings of 50 patients with pathologically proven chronic cholecystitis and 13 with gallbladder carcinomas were correlated with the pathological findings. RESULTS: In chronic cholecystitis with thickened wall, mucosa and muscle were shown in early images as smoothly delineated enhancement except in one case, and the subserosa with fibrosis was enhanced in late or delayed images. Unenhanced foci in the wall correlated with Rokitansky-Aschoff sinuses or mural stones. In carcinomas, all tumors showed irregularly delineated enhancement in early images. In late or delayed images, noncancerous portions were also enhanced. The outer margin of early enhancement correlated with the extension of the tumor. CONCLUSION: Dynamic MRI is useful for the differentiation of chronic cholecystitis from carcinoma and for the evaluation of its local extension.

Adult↗
PubMedDate not supplied

Histological influence on contrast-enhanced CT of pancreatic ductal adenocarcinoma.

PURPOSE: The purpose of our study was to examine the influence of the histology of pancreatic ductal adenocarcinoma on its appearance with contrast-enhanced CT. METHOD: Early-phase and late-phase dynamic CT images were obtained in 34 patients who underwent pancreaticoduodenostomy. The attenuating areas of the tumors (n = 58) on early- and late-phase images were classified as hyperattenuated, isoattenuated, hypoattenuated, or unenhanced. The histologic findings of these lesions were compared to the CT appearances. RESULTS: The isoattenuated areas on both early- and late-phase images histologically showed increasing cellularity of tumor cells (n = 1) or coexisting acinar tissues and tumor cells (n = 2) within the tumor. Hypoattenuated areas on early-phase images and isoattenuated or hyperattenuated areas on late-phase images (n = 27) showed dense fibrosis except in one tumor with an abscess. Hypoattenuated areas on early- and late-phase images and unenhanced areas (n = 28) showed mucin and/or necrosis within the tumor. CONCLUSION: The contrast-enhanced CT appearance of pancreatic ductal adenocarcinoma is influenced by the histologic features associated with tumor cells.

Aged↗
PubMedDate not supplied

Differentiation of hypervascular hepatic pseudolesions from hepatocellular carcinoma: value of single-level dynamic CT during hepatic arteriography.

PURPOSE: The purpose of our study was to assess the efficacy of single-level dynamic CT during hepatic arteriography (D-CTA) in the differentiation between hypervascular hepatocellular carcinoma (HCC) and hypervascular pseudolesion. METHOD: D-CTA was performed in nine cases with HCC and nine cases with pseudolesion. Findings on D-CTA were retrospectively analyzed. RESULTS: The transition of the stain of pseudolesion on D-CTA was divided into three phases: (1) inflow of the contrast material into the portal vein within the lesion, (2) lesion staining, and (3) fading out of the stain; that of HCC was divided into four phases: (1) inflow of CM into tumor, (2) tumor staining, (3) inflow of CM into the adjacent liver, and (4) coronal stain of adjacent liver. The coronal stain was seen in all HCCs but not in any pseudolesions. CONCLUSION: The present study suggest that D-CTA is a helpful option in the differentiation between HCC and pseudolesion.

Aged↗
PubMedDate not supplied

Pseudolesion in segment IV of the liver on MRI: prevalence and morphology in 250 cirrhotic livers compared with 250 normal livers.

PURPOSE: The goal of our study was to assess the prevalence of pseudolesion in segment IV of the liver on MRI in patients with and without liver cirrhosis. METHOD: Patients were divided into three groups: 10 patients with angiographically confirmed aberrant gastric venous drainage and liver cirrhosis (Group 1), 250 consecutively selected patients with liver cirrhosis (Group 2), and 250 with normal liver (Group 3). The signal intensity of pseudolesion in segment IV on T1- and T2-weighted MRI in the 510 patients was analyzed. RESULTS: In Group 1, five pseudolesions were visible and hyperintense on T1-weighted images. On T2-weighted images, four were visible and hypointense. In Group 2, 11 were seen (4.4%). All were hyperintense on T1-weighted images. Five were hypointense on T2-weighted images. In Group 3, one pseudolesion was seen (0.4%). CONCLUSION: The prevalence of pseudolesion in segment IV on MRI is higher in liver cirrhosis than in normal liver. The lesion is hyperintense on T1-weighted images when visible.

Adult↗
PubMedDate not supplied

Pseudolesion in segments II and III of the liver on CT during arterial portography caused by aberrant right gastric venous drainage.

We report three cases of pseudolesions caused by aberrant right gastric venous drainage (AGVD) in segment II/III of the liver as demonstrated on CT during arterial portography (CTAP). On CTAP, the lesions were seen as wedge-shaped perfusion defects, and on hepatic arteriography, AGVD directed to the area with the perfusion defect was visible in all three cases. When a perfusion defect is detected at the edge of segments II/III at CTAP, a pseudolesion caused by AGVD should be suspected.

Aged↗
PubMedDate not supplied

Resected case of hepatocellular carcinoma associated with lupoid hepatitis.

A 65 year old woman with lupoid hepatitis developed hepatocellular carcinoma which was diagnosed at an early stage. She had no history of blood transfusion and serum hepatitis B virus markers were negative. Prednisolone and 6-mercaptopurine were administered for the treatment of lupoid hepatitis. A hepatocellular carcinoma was detected by the elevation of serum alpha-fetoprotein and imaging studies. A tumour, 1.4 cm in diameter, was located in the lateral segment of the left hepatic lobe. It was resected by hepatic subsegmentectomy. Histological study showed a hepatocellular carcinoma of Edmondson type II against a background of posthepatitic cirrhosis. The patient was in good condition 2.5 years after the operation.

Aged↗
PubMedDate not supplied

Histopathology of portal tracts in livers after transcatheter arterial chemo-embolization therapy for hepatocellular carcinoma.

To study the influence of transcatheter arterial embolization therapy (TAE) on the portal tracts, 32 cases of hepatocellular carcinoma (HCC) with a history of TAE were examined. Portal tract elements are said to be mainly supplied by hepatic arterial blood, as is HCC. The following changes were found: peribile duct fibrosis; biliary epithelial injuries; bile duct necrosis; fibrous thickening of the intima and adventitia of arteries; thrombosis or stenosis of portal vein branches; and fibrosis of portal tract itself. We failed to correlate these histopathologic changes with the frequency of TAE or the interval between TAE therapy and surgery or autopsy. Semi-quantitative assessment disclosed that vessels of the peribiliary vascular plexus (PVP) which are known to be derived from hepatic arterial branches, were considerably decreased. There was little correlation between the degree of reduction of PVP and the observed histopathologic changes of portal tracts. It is suggested that TAE causes adverse effects on the elements of portal tracts and a reduction in the PVP in the vicinity of HCC, but the relationship between them is unclear.

Adult↗
PubMedDate not supplied

Occurrence of an intrahepatic porto-arterial shunt after hepatic artery embolization with Gelfoam powder in rats and rabbits.

Postmortem perfusion studies were carried out following hepatic artery embolization (HAE) with Gelfoam powder in rats (n = 17) and rabbits (n = 10). The inflow of barium particles into the hepatic arteries after portal vein injection (porto-arterial shunt: P-A shunt) was analyzed by stereomicroscopic and histologic examinations. A P-A shunt was observed in 12 of 17 rats (71%) following HAE (embolization group). The difference in occurrence rates of P-A shunt between control (1/12 = 9.2%) and embolization groups was statistically significant (chi 2, p less than 0.01) in rats. In rabbits, a P-A shunt was seen in only one of 10 animals in the embolization group. P-A shunting may have an important role in reconstructing the blood supply to hepatic tumors after HAE, and administration of anticancer drugs via the portal vein following HAE might be effective. However, the differences among different species of animals should be considered before clinical application.

Animals↗
PubMedDate not supplied

Endovascular embolization of unruptured vertebral dissection using Guglielmi electrolytically detachable coils: case report.

We present a patient with unruptured vertebral dissection whose angiograph showed further enlargement of the aneurysm, after a transient reduction in the size of the fusiform dilatation. Tolerance of parent artery occlusion was first confirmed by a balloon occlusion test. Both proximal and distal portions of the vertebral artery, including the dissected site, were occluded using Guglielmi electrolytically detachable coils; there were no complications. No new symptoms occurred during a 9-month follow-up period. For cases presenting with angiographic aneurysmal enlargement, embolization of the lesion using electrolytically detachable coils may be effective.

Aortic Dissection↗
PubMedDate not supplied

A case of ruptured mesenchymal chondrosarcoma of the pancreas.

A 25-year-old woman who underwent surgical removal of a right frontal meningeal mesenchymal chondrosarcoma in 1980 manifested abdominal pain and progressive anemia after a traffic accident in April 1997. CT disclosed a well-enhanced solid mass 2.5 cm in diameter with internal calcific deposits at the tail of the pancreas and a surrounding hematoma of 5.5 cm in diameter. Surgical resection revealed a ruptured metastatic mesenchymal chondrosarcoma of the pancreas.

Adult↗
PubMedDate not supplied

CT arteriographic confirmation of focal hepatic fatty infiltration adjacent to the falciform ligament associated with drainage of inferior vein of Sappey: a case report.

We experienced a case of focal fatty infiltration in the anteromedial edge of the medial segment of the liver adjacent to the falciform ligament associated with advanced esophageal cancer. By using CT during selective right internal thoracic arteriography, we confirmed that the inferior vein of Sappey drained into the area of focal fatty infiltration. This is the first case to directly establish the relationship between drainage of the inferior vein of Sappey and occurrence of focal fatty infiltration of the liver.

Angiography, Digital Subtraction↗
PubMedDate not supplied

Experience of two orbital MALT lymphomas treated with radiotherapy, and review of the literature.

Orbital MALT lymphoma is a relatively rare malignant disease, for which radiation therapy is effective. However, the optimal dose has not been determined. We experienced two cases of orbital MALT lymphoma. One patient was successfully treated, but the other developed a severe complication. We conclude that for safe treatment of orbital MALT lymphoma, a dose in excess of 40 Gy must not be delivered.

Aged↗
PubMedDate not supplied

Efficacy of transcatheter arterial embolization therapy for small hepatocellular carcinomas: comparison with other treatments.

A total of 155 cases of hepatocellular carcinoma smaller than 3 cm in greatest diameter were studied, and the survival rates obtained with various treatment methods were calculated. Patients were divided into an operated group (72 cases), transcatheter arterial embolization (TAE) group (52 cases), percutaneous ethanol injection therapy (PEIT) group (five cases), and a miscellaneous group (26 cases) according to the treatment received. The miscellaneous group included intraarterial chemotherapy, systemic chemotherapy, and no therapy. The survival rates of the operated and TAE groups were significantly higher than those of the miscellaneous group, but the survival rates of the TAE group decreased after two years had passed, and TAE showed limited long-term survival. In the PEIT group, the survival rates after three years were higher than those of the TAE group. TAE is effective for inoperable small HCC, but the indications for PEIT should be considered actively.

Adult↗
PubMedDate not supplied

Infectivity for chicken embryos of tissue-culture-modified infectious laryngotracheitis virus.

The present study shows the infectivity for chicken embryos of the SPL strain of tissue-culture-modified infectious laryngotracheitis (ILT) virus. The modified virus formed small pocks on the chorioallantoic membrane (CAM) and gave no adverse reaction after administration to chickens. For 1- and 6-day-old embryonated specific-pathogen-free (SPF) eggs, the SPL strain showed higher infectivity than virulent strain NS-175 or wild strains of ILT virus. A high percentage of embryos of day-old eggs inoculated with strains SPL via the yolk sac died within several days, and virus was recovered from yolk and embryos with high titer. In the embryos inoculated at 6 days of age, histopathological lesions characterized by syncytium formation with intranuclear inclusion bodies were observed mainly in the CAM, liver cells, epithelial cells of the oral cavity, and esophagus and rarely in epithelial cells of the uriniferous tubule, bronchus, trachea, choroid plexus, or feather follicles. In the 10-day-old embryonated SPF eggs inoculated via the chorioallantoic cavity, however, the SPL strain demonstrated low pathogenicity compared with strain NS-175 and the two wild strains.

Animals↗