Search PubMed⌕ Search

Biomedical subjects

A Tasaka

Publications and source records attributed to A Tasaka.

At least 37 records · Page 2Linked to original sources
PubMed1981

Lobar attenuation difference of the liver on computed tomography.

Lobar attenuation difference of the liver was demonstrated by computed tomography (CT) in 16 cases among over 1,000 cases in which CT scans of the liver were obtained. Cases were divided into two groups: with liver tumor and without liver tumor. Among the former group, hepatocellular carcinomas is the predominant lesion; tumor thrombus in the portal vein is presumably the cause of the attenuation difference. The latter group includes the patients with hepatocellular disease and clinically normal patients. In the former group, the tumor itself could not be noted in precontrast scans in eight out of 12 cases. When lobar attenuation difference of the liver is noted, a postcontrast scan should be obtained to determined whether there is a liver tumor in the lobe of lower attenuation.

Adult↗
PubMed1981

Computed tomography of localized dilatation of the intrahepatic bile ducts.

Twenty-nine patients showed localized dilatation of the intrahepatic bile ducts on computed tomography, usually unaccompanied by jaundice. Congenital dilatation was diagnosed when associated with a choledochal cyst, while cholangiographic contrast material was helpful in differentiating such dilatation from a simple cyst cy showing its communication with the biliary tract when no choledochal cyst was present. Obstructive dilatation was associated with intrahepatic calculi in 4 cases, hepatoma in 9, cholangioma in 5, metastatic tumor in 5, and polycystic disease in 2. Cholangioma and intrahepatic calculi had a greater tendency to accompany such localized dilatation; in 2 cases, the dilatation was the only clue to the underlying disorder.

Adenoma, Bile Duct↗
PubMed1981

[Clinical significance of RCT in liver diseases (author's transl)].

Radionuclide Computed Tomography (RCT) was performed in 40 cases with various liver diseases. Indication of RCT was determined by the fact that usual liver scintigrams showed or suspected space-occupying lesion. In diffuse hepatocellular disease, RCT added diagnostic informations in 10 out of 17 cases. In these patients, RCT referred decreased uptake area to morphological change such as prominent porta hepatis, widening of both lobes or lateral seg. and medial seg, of the left lobe, and so on. In cases with liver tumor, RCT demonstrated the liver by axial plane, so one could easily or precisely diagnose the location of the mass. RCT performance requires only 30 min, additionally, and no additional injection. We conclude RCT should be performed to the patients whose liver scintigrams show or suspect space-occupying lesion.

Adult↗
PubMed1980

CT patterns of mural thrombus in aortic aneurysms.

The computed tomography (CT) scans of 71 cases of arteriosclerotic and/or dissecting aortic aneurysms (33 thoracic, 25 abdominal, and 13 thoracoabdominal) were analyzed. Enlargement was seen in all cases, and deformity of aorta was found in 92%. Mural thrombus was evident on CT in 86% of the cases, and its pattern was classified into eight types. The most frequent was the ring type (Type A) followed by the left crescent thrombus (Type H) and the left posterior crescent thrombus (Type D). Calcification was found in 60 cases, and intraluminal calcification was seen in 14 cases.

Aortic Dissection↗
PubMed1980

Computed tomography and ultrasound in the diagnosis of intrahepatic calculi.

Computed tomography (CT) and ultrasound were used to evaluate intrahepatic biliary calculi in 16 patients. Thirteen demonstrated high-density shadows in dilated intrahepatic ducts on CT. Of the 11 who also underwent ultrasonography, 7 had positive findings. Strong echoes with acoustic shadows in dilated intrahepatic biliary ducts are diagnostic of stones. CT and ultrasound are useful in evaluating intrahepatic calculi, with CT being particularly helpful in postoperative cases.

Adult↗
PubMed1980

Computed tomography of cavernous hemangioma of the liver.

Twelve cases of hepatic hemangioma were examined by computed tomography (CT). Dense accumulations of rapidly injected contrast material in or near the periphery of the lesions were demonstrated in early postcontrast scans. They invaded the area of low density and diminished in attenuation value with time. This marked decrease of the low density area noticed in the precontrast scan was also seen in the later postcontrast scan. These findings were recognized in all 10 cases of hemangioma examined with contrast enhancement, while no cases of hepatoma showed such a peripheral high density zone. Most hepatic hemangiomas could be correctly diagnosed by CT alone.

Adult↗
PubMed1980

Computed tomography of gallbladder carcinoma.

Twenty-seven gallbladder carcinomas were examined by computed tomography (CT). All patients had abnormal CT findings, suggesting a gallbladder lesion in 26. Based on the major CT findings, gallbladder cancer was classified as "massive," "thickened wall," or "intraluminal." Twenty cases were diagnosed correctly as cancer: on retrospect, definite findings of gallbladder cancer were observed in 24 and equivocal or misleading signs in 3. Some cases of chronic cholecystitis and liver tumor were difficult to differentiate from gallbladder cancer. Direct hepatic extension was easily seen, but lymph-node metastases and bile-duct extension were difficult to distinguish.

Adenocarcinoma↗
PubMed1980

CT of choledochal cyst.

Ten preoperative cases of choledochal cyst and five patients who had had complications after surgical treatment for their choledochal cysts were studied to evaluate the accuracy of computed tomography (CT) in the diagnosis of this malformation and its complications. Choledochal cysts were accurately diagnosed by CT in seven and suggested in three of the 10 preoperative patients. CT provided the correct diagnosis in all six patients with intrahepatic involvement. The CT pattern of congenital dilatation of the intrahepatic ducts was strikingly different from that of an acquired obstructive one. CT was also effective in the postoperative follow-up patients. In addition, within this group of 15 patients, three choledochal cyst cancers were detected.

Adolescent↗
PubMed1980

Dynamic CT densitometry of hepatic tumors.

Forty-two patients with hepatic tumors were examined by serial computed tomography (CT), using bolus injection of contrast medium. Scanning was at 15, 60, and 120 sec postinjection at a slice level containing the tumor. The densities of the tumor, liver, and aorta were sampled on these and on precontrast CT images. The tumors were divided into four types according to the pattern derived by sequential plotting of the density difference between the tumor and the liver parenchyma. Type I manifested rapid and prolonged high tumor enhancement, in type II the tumor was enhanced rapidly but then quickly became less dense than the liver, in type III there was no significant change over time in the density difference between the tumor and the liver, and type IV showed no, or very little, tumor enhancement. All cavernous hemangiomas belonged to type I while two-thirds of the hepatomas wer type II. There was a good correlation between tumor vascularity on CT and angiography. We suggest that dynamic serial CT scanning technique may be an improvement over the conventional drip-infusion technique in assessing liver tumors.

Absorptiometry, Photon↗
PubMed1979

Computed tomography in the evaluation of hepatocellular carcinoma.

Computed tomography (CT) was used to evaluate 47 cases of hepatocellular carcinoma: it was definite in 37, equivocal in 5 and negative in 5 cases. No specific patterns of CT images were recognized. Pre- and postcontrast scans were necessary because several tumors could only be detected on one or the other scan. CT may reveal the exact extent of tumor and show additional tumors in case of multiple lesions. However, false negative results are possible in isodense or very small tumors.

Adult↗