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O Matsui

Publications and source records attributed to O Matsui.

At least 55 records · Page 3Linked to original sources
PubMed1999

The efficacy of CT arteriography for spinal arteriovenous fistula surgery: technical note.

We performed helical computed tomography with contrast injection into feeding arteries through a selectively introduced microcatheter to provide precise definition of the vascular and bony structure of the spine in patients with spinal arteriovenous fistula. This selective CT arteriography reliably showed structures including abnormal epi- and intradural feeding arteries, the fistula, perimedullary draining veins and surrounding vertebrae preoperatively with a minimal contrast medium load. This technique can facilitate safe, minimally invasive surgical obliteration of the fistula and a favorable outcome.

Angiography↗
PubMed1999

Correlation between the blood supply and grade of malignancy of hepatocellular nodules associated with liver cirrhosis: evaluation by CT during intraarterial injection of contrast medium.

OBJECTIVE: The purpose of this study is to evaluate the correlation between the intranodular blood supply revealed by CT during intraarterial injection of contrast medium, mainly using helical CT, and the grade of malignancy of hepatocellular nodules associated with liver cirrhosis as classified by the International Working Party of the World Congress of Gastroenterology. SUBJECTS AND METHODS: We studied 201 histologically proven nodules (101 resected and 100 biopsied nodules), including 47 low-grade dysplastic nodules (low-DNs), 56 high-grade dysplastic nodules (high-DNs), 24 well-differentiated hepatocellular carcinomas (wd-HCCs), and 74 moderately or poorly differentiated HCCs (mp-HCCs), in 139 cirrhotic patients. Findings on CT during arterial portography (n = 201) and CT during hepatic arteriography (n = 74) were reviewed and compared with the histologic diagnosis. RESULTS: CT findings were classified into four types relative to the surrounding liver: type A (isodense), type B (slightly hypodense), type C (partially hypodense), and type D (markedly hypodense) on CT during arterial portography and type I (isodense), type II (hypodense), type III (partially hyperdense), and type IV (hyperdense) on CT during hepatic arteriography. On CT during arterial portography, the distributions of each type were low-DN (n = 47 [A, n = 36; B, n = 8; C, n = 3]), high-DN (n = 56 [A, n = 18; B, n = 20; C, n = 10; D, n = 8]), wd-HCC (n = 24; [B, n = 4; C, n = 13; D, n = 7]), and mp-HCC (n = 74 [D, n = 74]). On CT during hepatic arteriography, the distributions were low-DN (n = 26 [I, n = 18; II, n = 7; III, n = 1]), high-DN (n = 19 [I, n = 6; II, n = 7; III, n = 4; IV, n = 2]), wd-HCC (n = 15 [I, n = 1; III, n = 8; IV, n = 6]), and mp-HCC (n = 14 [IV, n = 14]). We found a statistically significant correlation between the four types and the grade of malignancy of these nodules. CONCLUSION: Findings on CT during arterial portography and CT during hepatic arteriography correlated positively with histologic grading when overlap in appearance between dysplastic nodules and HCCs occurred. The concept revealed in this study can apply to diagnoses made on the basis of Doppler sonography, dynamic CT, and MR imaging.

Aged↗
PubMed1999

Saline-jet aspiration thrombectomy catheter. Clinical results in patients with venous thrombosis.

PURPOSE: To evaluate hydraulic thrombectomy using a saline-jet aspiration thrombectomy catheter in the treatment of venous thrombosis. MATERIAL AND METHODS: Ten patients underwent 12 hydraulic thrombectomy procedures using 2.7 or 4.0 mm catheters. The site of the thrombus was either central, peripheral or in portal veins. The age of the thrombi was between 2 and 60 days (mean 19.7 days). The efficacy of hydraulic thrombectomy was evaluated based on the aspirated thrombus ratio (ATR), i.e. the volume of the thrombus aspirated divided by the volume of the thrombus before thrombectomy. ATR was estimated by comparing the angiograms of the lesion before and after thrombectomy. RESULTS: Soft thrombi were usually rapidly removed. ATR was >2/3 in 3, 2/3-1/3 in 2, 1/3-0 in 4, and 0 in 1 patient. The activation time of the injector was 23-224 s (mean 102 s) and the volume of aspirated blood was 30-680 ml (mean 250 ml). Compensatory infusion of saline was performed for blood loss, and 400 ml of packed red blood cells was transfused in 1 patient. No complications of the hydraulic thrombectomy were observed. Thrombolysis or additional treatment were performed in 9 patients. CONCLUSION: Hydraulic thrombectomy using this catheter can contribute to the treatment of venous thrombosis.

Equipment Design↗
PubMed1998

Distribution of intrahepatic mast cells in various hepatobiliary disorders. An immunohistochemical study.

There is evidence that mast cells are involved in a number of pathophysiological processes. The significance of mast cells in hepatic fibrosis was examined in 28 patients with histologically normal livers, 34 with acute liver diseases, 51 with chronic liver diseases, and 59 with cholestatic biliary diseases, using immunostaining of the mast cell-specific proteinase, tryptase. Mast cells that were positive for tryptase and for chymase were significantly increased in frequency in fibrotic portal tracts and fibrous septa, particularly in cholestatic/biliary diseases. Mast cells were also increased in frequency around the fibrotic septal and intrahepatic large bile ducts and peribiliary glands of biliary diseases. However, they were less common or even rare in the sclerotic bile ducts and in scarred portal or septal fibrosis. More than half of these more numerous mast cells were positive for histamine, and some were also positive for basic fibroblast growth factor. These two substances were detectable by immunoelectron microscopic in the cytoplasmic granules of mast cells. In contrast, mast cell numbers were not significantly increased in acute viral or drug-induced hepatitis, or in zones 2 and 3 of the hepatic acinus with respect to pericellular and perivenular fibrosis in chronic liver diseases. These findings suggest that mast cells increase in number in cholestatic/biliary diseases, and to a lesser degree in chronic liver diseases, and are involved in the active fibrous enlargement of portal tract and fibrous septa formation and also in the fibrosis of the intrahepatic bile ducts as they display fibrosis-promoting factors such as tryptase, fibroblast growth factor and histamine.

Acute Disease↗
PubMed1998

A case of progressive multiple focal nodular hyperplasia with alteration of imaging studies.

Focal nodular hyperplasia (FNH) of the liver is a lesion characterized by a well circumscribed region of hyperplastic liver tissue with stellate fibrosis. The pathogenesis of the lesion is unknown but various authors consider that FNH may be a response to a preexisting vascular abnormality. We experienced a case of progressive multiple FNH, in which the hemodynamic change as shown by imaging modalities, may support this hypothesis. The patient, a 38-yr-old woman, was found by chance to have multiple portal venous shunts and multiple FNH in both lobes of her liver. Because of their benign characteristics, we followed the nodules periodically without any special treatment. After about 4 yr, the nodules increased both in size and number. In addition, digital subtraction angiography showed that the diameter of the artery had become larger. The hemodynamic change revealed by imaging studies in this case supports the hypothesis that one of the pathogens of FNH is a secondary hepatocellular response to arterial hyperperfusion caused by some vascular malformations.

Adult↗
PubMed1998

Hypervascular hepatocellular carcinoma: evaluation of hemodynamics with dynamic CT during hepatic arteriography.

PURPOSE: To assess the hemodynamics and the main drainage vessel of hypervascular hepatocellular carcinoma. MATERIALS AND METHODS: Single-level dynamic computed tomography during hepatic arteriography (CTHA) was performed in 32 patients with hepatocellular carcinoma. Carcinoma was confirmed with histologic (n = 9) or clinical (n = 23) examination results. Single-level CTHA findings were retrospectively analyzed. Histologic specimens from 40 livers with hepatocellular carcinoma were also examined, with special attention to vessels along the rim of the lesion. RESULTS: Contrast material enhancement on single-level CTHA images occurred in four phases: (a) inflow of the contrast material into tumor, (b) tumor enhancement, (c) inflow of the contrast material into adjacent liver, and (d) corona enhancement of adjacent liver. Corona enhancement was seen in all lesions. A bright branching structure in the corona enhancement area, suggestive of a portal venule, was visible at the start of adjacent liver staining in 21 lesions. Continuity between a tumor sinusoid and a tiny vessel in the inner layer of the pseudocapsule was histologically confirmed in 10 of 40 specimens. Continuity between a tiny vessel in the inner layer and a portal vein in the outer layer of the pseudocapsule was confirmed with findings on serial sections from one liver. CONCLUSION: The main drainage of hepatocellular carcinoma lesions may be a protal venule.

Carcinoma, Hepatocellular↗
PubMed1998

Analytical histopathological diagnosis of small hepatocellular nodules in chronic liver disease.

Due to the recent progress in radiology and increased clinical and pathological interest, small hepatocellular nodules about 1 cm in size are frequently being detected in patients with chronic liver disease, particularly liver cirrhosis. Two new types of small hepatocellular nodules are now known: low-grade hepatocellular carcinomas (HCC) and dysplastic nodules, in addition to the previously known HCC (classical) and regenerative nodules. Ultrasound-guided needle biopsies from these nodules are routinely used for the differential diagnosis. For comparison, a simultaneous needle biopsy from the liver remote from the nodule is strongly recommended. Low-grade HCC, which are different from classical HCC in their morphological atypia and also biological behaviors, show local invasion into the portal tracts and surrounding hepatic parenchyma, but not intrahepatic or extrahepatic metastasis. Dysplastic nodules show mild cellular and structural atypia, a finding which is not sufficient for making a diagnosis of malignancy. An increased nuclear/cytoplasmic (N/C) ratio and nuclear crowding, small cell-dysplasia, increased cytoplasmic staining, clear cell change, pseudogland formation, and fatty change of hepatocytes are variably seen in these nodules. Nuclear changes, local invasion to the portal tract and surrounding liver, and loss of the reticulum fibers along the hepatocytes are useful markers favoring low-grade HCC rather than dysplastic nodules. These low-grade HCC and dysplastic nodules should also be distinguished from classical HCC as well as large-sized regenerative nodules. A comparative analysis of the histological findings observed in individual nodules is a reasonable approach to differential diagnosis at present. The recognition and analysis of these two new hepatocellular nodules may augur a new horizon in the study of hepatocellular neoplasm.

Adenoma↗
PubMed1998

[Usefulness of T2-weighted images using single shot fast spin echo (SSFSE) pulse sequence for the evaluation of pancreatobiliary diseases: comparison with MRCP using SSFSE].

Single shot fast spin echo (SSFSE) pulse sequence provides us with a thick single-slice MR cholangiopancreatography (MRCP) as well as thin multi-slice MRCP, and T2-weighted images are also obtained with SSFSE sequences. In comparison with conventional spin-echo and fast spin-echo sequences, T2-weighted image using SSFSE sequence has the advantages of the abscence of motion artifacts and the extremely short acquisition times. MRCP using SSFSE sequence is useful in the conspicuity of bile duct, pancreatic duct, and cystic lesions. However, T2 weighted image using SSFSE is superior to MRCP not only for the differentiation between solid and cystic lesions but also for the visualization of contour of different organs and lesions.

Biliary Tract Diseases↗
PubMed1997

Hepatic hilar inflammatory pseudotumor mimicking cholangiocarcinoma with cholangitis and phlebitis--a variant of primary sclerosing cholangitis?

Inflammatory pseudotumor (IPT) of the liver is rare. We present a case of hepatic IPT mimicking cholangiocarcinoma in which the tumor was located at the left porta hepatis. The patient was a 64-year-old man in whom abnormal liver function test results had been noted incidentally during an annual health checkup in 1993: the patient declined to go to the hospital for further examination. At the annual health checkup the following year, abnormal liver function test results were noticed again, and this time he did go to a hospital, where a hepatic mass was found. Laboratory test results were unremarkable. Based on the location of the lesion and the findings of a variety of imaging modalities, such as ultrasound and computed tomography examination, the lesion was preoperatively diagnosed as hilar cholangiocarcinoma and was surgically resected. Pathologic examination of the resected lesion, however, revealed that it was not a true tumor but an inflammatory pseudotumor with marked destructive and sclerosing cholangitis mimicking primary sclerosing cholangitis (PSC) and obliterative phlebitis. Since the location and features of the tumor in the present case are very pertinent to the relationship between IPT and PSC, we describe its clinical and histologic features and discuss the findings in relation to PSC in the context of our literature review.

Bile Duct Neoplasms↗
PubMed1997

Aberrant gastric venous drainage in a focal spared area of segment IV in fatty liver: demonstration with color Doppler sonography.

PURPOSE: To clarify the correlation between aberrant gastric venous drainage and a focal spared area at the posterior edge of segment IV in fatty liver by using color Doppler ultrasound (US). MATERIALS AND METHODS: Seventeen patients with fatty liver were examined with gray-scale, color Doppler, and power Doppler US. In one patient with a focal spared area, arteriography and computed tomography (CT) were performed during injection of contrast medium into the right gastric artery. RESULTS: Focal spared areas of fatty liver at segment IV were shown in five of 17 patients. In all five patients with a focal spared area, aberrant gastric venous drainage was observed with color Doppler US. Power Doppler US depicted aberrant gastric venous drainage more clearly than color Doppler US. On the other hand, no definite aberrant gastric venous drainage was seen in the 12 patients who had no focal spared area. In one patient who underwent selective arteriography of the right gastric artery and CT arteriography, aberrant gastric venous drainage into segment IV was directly demonstrated. CONCLUSION: Focal spared areas at segment IV in fatty liver correlate strongly with aberrant gastric venous drainage. Noninvasive imaging methods such as color and power Doppler US are useful for depicting these aberrant drainage veins.

Adult↗
PubMed1997

Posterior aspect of hepatic segment IV: patterns of portal venule branching at helical CT during arterial portography.

PURPOSE: To determine the anatomy of the portal venous system in the posterior aspect of segment IV of the liver by using helical computed tomography (CT) during arterial portography (CTAP). MATERIALS AND METHODS: One hundred consecutive patients underwent CTAP. Helical CT during hepatic arteriography was performed in 20 patients. In seven patients with hepatocellular carcinoma in the posterior aspect of segment IV, the feeding arteries were also analyzed. RESULTS: A venule from the intrahepatic portal vein to segment IV was seen in all patients. Other findings included a tiny venule from the distal part of the main left portal vein (n = 36), from the proximal left main portal vein (n = 20), and from the right portal vein (n = 18). Aberrant right gastric venous drainage and/or parabiliary venous drainage directly into the posterior aspect was present in 14 patients. In two patients, a tiny accompanying artery was seen on images from CT during hepatic arteriography. In seven patients with hepatocellular carcinoma, the main feeding artery branched from the right (n = 2) or left (n = 5) hepatic artery. CONCLUSION: CTAP adequately demonstrates the tiny portal venous and arterial branches from the main right or left portal vein that distribute to the posterior aspect of segment IV. Knowledge of this vascular anatomy is clinically important.

Adult↗
PubMed1997

[Usefulness of the interlocking detachable coil for the repeatedly ruptured dissecting aneurysm of the vertebral artery in the acute stage].

A 44-year-old male with a repeatedly ruptured dissecting aneurysm of the vertebral artery (VA) manifesting with subarachnoid hemorrhage was successfully treated with endovascular surgery using an interlocking detachable coil (IDC). He had a dissecting aneurysm in the left VA distal to the left posterior inferior cerebellar artery (PICA). Because the dissecting aneurysm ruptured repeatedly and his clinical condition was moribund, direct surgery was not indicated. The dissecting aneurysm was embolized with an IDC and additional platinum coils. Among patients with a ruptured VA dissecting aneurysm, proximal occlusion is generally indicated. But the direct embolization of a dissecting aneurysm can be applied in cases in which the aneurysm is ruptured repeatedly in the acute stage. IDC is a useful and safe material for endovascular surgery of a ruptured VA dissecting aneurysm.

Acute Disease↗
PubMed1996

Cruveilhier-Baumgarten syndrome in which venous hum disappeared following endoscopic variceal sclerotherapy.

We report a case of Cruveihier-Baumgarten syndrome associated with portal vein thrombosis that developed, slowly during a 2-year period after endoscopic variceal sclerotherapy. The thrombosis led to the disappearance of the venous hum and the dilated abdominal wall veins characteristic of this syndrome. A 73-year-old woman was hospitalized for treatment of esophageal varices in April 1988. Her spleen was markedly enlarged, and the histologic findings of her liver were not consistent with hepatic cirrhosis, but with idiopathic portal hypertension. A venous hum was audible in the upper abdomen. Superior mesenteric angiography revealed a porto-systemic shunt vessel under the abdominal wall, originating from the umbilical vein. She was injected four times with a sclerosant, and this brought about disappearance of the esophageal varices. Two years after the first admission, the venous hum was no longer audible, but there was a recurrence of the esophageal varices. More than 2 years later (4 years after the first admission), ultasonographic study, computed tomography, and angiography showed a large thrombus, which completely obstructed the portal vein at the origin of the umbilical vein, and the development of collateral vessels, seen as a "cavernous transformation."

Aged↗
PubMed1996

Angiomyolipoma mimicking true lipoma of the liver: report of two cases.

Hepatic angiomyolipoma (AML) is very rare and only about 80 cases have been reported. The tumor is fundamentally heterogeneously composed of the three tissue components of blood vessels, smooth muscle cells (SMC), and fat cells. Two cases of hepatic AML are reported here, both of which are histologically composed predominantly of a fat cell element and resembled true lipoma (lipomatous AML). However, careful examination of both tumors revealed the presence of a small amount of epithelioid SMC, especially around blood vessels. Immunohistochemical study using monoclonal antibody for melanoma (HMB-45) clearly revealed a small amount of HMB-45-positive SMC around the blood vessels and scattered in the diffuse fat cell growth in both tumors. Since no liver tissue components or primary liver tumors are reactive with HMB-45 except AML cells, the presence of HMB-45-positive cells within the tumor clearly established the diagnosis of hepatic AML. Any fatty tumor or focal fatty lesion of the liver that superficially resemble true lipomas should be tested for the presence of HMB-45-positive SMC in the tumor to differentiate it from AML.

Aged↗