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Biomedical subjects

M C Han

Publications and source records attributed to M C Han.

At least 163 records · Page 9Linked to original sources
PubMed1989

Biliary cystadenoma and cystadenocarcinoma: CT and sonographic findings.

Eight women (ages 18-65 years; mean, 47 years) with biliary cystadenoma (n = 3) or cystadenocarcinoma (n = 5) were examined with computed tomography and sonography. The appearance of the tumors varied from unilocular cystic masses to multilocular cystic masses with multiple satellite tumors, although the majority (n = 6) of tumors were single, multilocular, and cystic. Cystic areas showed attenuation numbers under +30 HU. Papillary excrescences, nodular thickening of internal septa, and mural nodules, which showed contrast enhancement, were seen in one case of cystadenoma and all five cases of cystadenocarcinoma. One cystadenoma and one cystadenocarcinoma contained calcifications. Three cases showed connection to the intrahepatic bile ducts. Biliary cystadenoma and cystadenocarcinoma should be the primary diagnostic consideration when one detects in a middle-aged woman a well-encapsulated, multilocular cystic mass connected to the biliary system or prolapsing into the bile duct.

Adult↗
PubMed1989

Hilar cholangiocarcinoma: comparative study with sonography and CT.

Fifty-one patients were studied to determine the relative accuracy of sonography and computed tomography (CT) in the evaluation of hilar cholangiocarcinoma. Both sonography and CT permitted detection of intrahepatic bile duct dilatation in all patients. Nonunion of right and left intrahepatic bile ducts was identified with sonography in 90% and with CT in 94% of patients. The tumor per se was depicted by sonography in 21% and by CT in 40% of patients. Forty tumors (78%) were of the infiltrating type, seven (14%) were exophytic, and four (8%) were polypoid. With sonography, infiltrating and exophytic tumors were difficult to depict, whereas polypoid tumors were well identified. With CT, infiltrating tumors were more difficult to depict than were exophytic or polypoid tumors. On CT scans, depicted tumors of the infiltrating type showed high attenuation and an indistinct margin, whereas exophytic and polypoid tumors showed low attenuation and a well-defined margin. Sonography and CT were comparably accurate in determining the level of obstruction in hilar cholangiocarcinoma even when no mass was depicted. CT was superior to sonography in depicting tumor per se and in demonstrating associated findings.

Adenoma, Bile Duct↗
PubMed1989

Small hepatocellular carcinoma: detection with sonography, computed tomography (CT), angiography and Lipiodol-CT.

Seventy-three small hepatocellular carcinomas under 5 cm in diameter in 47 patients were examined by sonography, computed tomography (CT), hepatic angiography and CT after intra-arterial injection of iodized poppy-seed oil (Lipiodol-CT). The imaging techniques that first led to detection of small hepatocellular carcinomas were sonography in 53 cases (72.6%), CT in 10 (13.7%), angiography in eight (11%) and Lipiodol-CT in two (2.7%). Sensitivity for detecting small hepatocellular carcinomas was 73% with sonography, 82% with CT, 86% with angiography and 96% with Lipiodol-CT. As a screening method, sonographic and CT results in detecting small hepatocellular carcinomas were not significantly different (p greater than 0.05). Lipiodol-CT was superior to sonography (p less than 0.01), CT (p less than 0.01) and angiography (p less than 0.05) in detecting small hepatocellular carcinomas. We believe that the combined use of Lipiodol-CT with screening methods such as sonography or CT is indispensable for the accurate detection of small hepatocellular carcinomas.

Angiography↗
PubMed1989

CT findings of clonorchiasis.

Clonorchiasis is a snail-transmitted trematodiasis caused by Chinese liver fluke, Clonorchis sinensis. Forty-two patients with the disease were examined with CT. Seventeen patients had clonorchiasis alone, and 25 patients had clonorchiasis with hepatobiliary malignancies (20 cholangiocarcinomas, four hepatocellular carcinomas, one carcinoma of the ampulla of Vater). In three of the 17 patients with clonorchiasis alone, the CT scans were normal. In 14 patients (82%), CT showed diffuse, minimal, or mild dilatation of the intrahepatic bile ducts. None of the patients had marked dilatation. The extrahepatic biliary tree was normal in all 17 patients. All 25 patients with clonorchiasis and hepatobiliary malignancies had diffuse dilatation of the intrahepatic bile ducts on CT, including 18 patients with minimal or mild dilatation and seven patients with marked dilatation. All seven patients with marked dilatation had extrahepatic biliary malignancies. Clonorchis sinensis per se or thickening of the bile duct wall could not be recognized on CT scans. Additional abnormalities evident on CT included pyogenic liver abscesses in two patients and gallstones in five patients. The diagnosis of clonorchiasis can be suspected when CT shows diffuse, uniform, and minimal or mild dilatation of the intrahepatic bile ducts, particularly in the periphery of the liver, without evidence of extrahepatic biliary dilatation.

Adenoma, Bile Duct↗
PubMed1989

Leptospirosis of the lung: radiographic findings in 58 patients.

Leptospirosis is the disease produced by any of the group of spirochetes of the genus Leptospira. The main organs involved are the liver, central nervous system, kidneys, skeletal muscle, and lungs. Thirty-seven (64%) of 58 patients with leptospirosis, proved by positive serology, had pulmonary radiographic findings. Three radiographic patterns were evident: (1) 21 (57%) of the 37 patients had small nodular densities, (2) six (16%) had large confluent areas of consolidation, and (3) 10 (27%) had diffuse, ill-defined, ground-glass density. Serial radiographs showed a tendency for the nodular pattern to be followed by confluent consolidation and/or ground-glass density. Abnormalities were bilateral, nonlobar in all cases, and had a marked tendency toward peripheral predominance. Pulmonary abnormalities resolved within 15 days, except in eight patients who died because of respiratory failure (six patients) or other causes (two patients). In order to correlate pathology with the radiographic findings, Leptospira, isolated from a patient, was injected intraperitoneally into 20 guinea pigs. All lungs from the guinea pigs showed petecheal hemorrhage, which progressed to large confluent areas of hemorrhage. The typical pulmonary radiographic findings of leptospirosis are compatible with the multifocal pulmonary hemorrhage seen in the guinea pigs.

Adult↗
PubMed1989

Giant cavernous hemangioma of the liver: CT and MR imaging in 10 cases.

Ten giant cavernous hemangiomas of the liver in eight patients were examined with both MR imaging and dynamic bolus CT. The maximal diameters of the tumors were 6.5-19 cm (mean, 10.8 cm). MR imaging was done with a 2.0-T superconducting magnet and spin-echo imaging. CT was done with single-bolus dynamic scans. On MR images, all 10 hemangiomas had a heterogeneous appearance. The main part of the tumor comprised uniform, well-defined, high-intensity areas on T2-weighted images, with increasing intensity ratios with prolongation of TR and TE. Other parts of the tumor were cleftlike and were of lower intensity than the remainder of the tumor on T1-weighted images and of higher intensity on heavily T2-weighted images. These parts corresponded to the areas of the tumor that were of lower density on dynamic bolus CT scans. Internal septa in the tumor of low intensity were also noted on all MR pulse sequences. These parts corresponded to low-density areas on delayed contrast-enhanced CT. Familiarity with the characteristics of the internal architecture of giant cavernous hemangiomas on MR imaging or dynamic bolus CT might be useful in making the correct diagnosis of this tumor.

Adult↗
PubMed1989

Takayasu arteritis: angiographic findings and results of angioplasty.

Takayasu arteritis is a systemic disease characterized by occlusion of the aorta and its branches. We performed coronary angiography and thoracic and abdominal aortography on 47 patients with Takayasu arteritis. Angiographic findings included arterial stenosis, occlusion, or aneurysm. The left subclavian artery was involved in 26 cases (55%), the abdominal aorta in 25 cases (53%), the right renal artery in 21 cases (45%), the right subclavian and left renal arteries in 18 cases (38%), the descending thoracic aorta in 15 cases (32%), and the left common carotid artery in 14 cases (30%). The coronary arteriograms in the 47 patients showed coronary involvement in seven (15%). Proximal or osteal lesions were present in six cases. Percutaneous transluminal angioplasty was performed successfully in eight patients for treatment of three aortic lesions, nine renal artery lesions, one subclavian artery lesion, and one coronary artery lesion. In the three cases with recurrence after 4-7 months, repeated angioplasty was successful. For appropriate management of Takayasu arteritis, we suggest thorough angiographic evaluation and proper intervention, including percutaneous transluminal angioplasty in selected cases for revascularization.

Adolescent↗
PubMed1989

Microcholangiography. Normal microbiliary system and its alteration after extrahepatic bile duct obstruction.

The authors used microcholangiography to demonstrate the feasibility of the technique and the features of the normal and the obstructed biliary systems. Furthermore, they attempted to explain the pathophysiology of cholangiography-related septicemia with this technique. Extrahepatic bile ducts (EHBD) of 40 rabbits were ligated, and microcholangiography was carried out with infusion of barium suspension immediately as well as one, three, and five days after ligation. Microradiographic technique was used and the findings were correlated with histopathologic features. The intrahepatic microbiliary system such as interlobular bile ducts and ductules were well visualized. After EHBD ligation, ductules were tortuously dilated. The histologically observed ductular proliferation in many hepatobiliary diseases could be attributed in part to the tortuosity of bile ductules, particularly when biliary obstruction is present. Regurgitation of barium into hepatic sinusoids was demonstrated in 36 rabbits (90%) and probably was caused by rupture of interlobular bile ducts and ductules.

Animals↗
PubMed1988

Sonographic appearance of Krukenberg tumor from gastric carcinoma.

Sonographic findings in 16 cases of Krukenberg tumor from gastric carcinoma were analyzed. The patients' ages ranged from 25 to 52 years (mean 42 years). The tumor involved both ovaries in 14 patients with asymmetrical masses in 9 of 14 cases. Ascites was noted in 15 cases. Echogenicity of the tumor varied from solid to predominantly cystic: solid in 8, mixed in 6, and predominantly cystic in 2 cases. Solid masses tended to be smaller than mixed or cystic masses. The primary gastric carcinoma had been diagnosed before emergence of the tumors in only 7 cases. The findings suggest that in relatively young patients with ovarian mass, particularly bilateral tumors, careful evaluation for gastrointestinal tract involvement should be done.

Adult↗
PubMed1988

Exogastric cystic gastric leiomyoblastoma with unusual CT appearance.

Gastric leiomyoblastomas are rare tumors between leiomyomas and leiomyosarcomas in terms of their malignant potential. This article describes 2 cases of exogastric cystic gastric leiomyoblastoma with unusual location and computed tomographic (CT) appearance. The CT findings of these cases were unlike those of usual smooth muscle tumors, but closely simulated cystadenomatous tumor of the ovary or pancreas.

Aged↗
PubMed1988

Solid and papillary epithelial neoplasms of the pancreas: CT findings.

Five female patients and one male patient with solid and papillary epithelial neoplasms of the pancreas were examined with computed tomography (CT). The mean age of the patients was 27 years (range, 13-46 years). All cases showed well-encapsulated, round or lobulated masses consisting of both cystic and solid areas. Cystic portions showed CT numbers that suggested hemorrhagic necrosis. There were no internal septations within the masses. In three tumors located in the head of the pancreas, dilatation of the biliary tree was absent or minimal, although the masses were large. Two tumors contained calcifications. One tumor demonstrated metastatic deposits in liver and lymph nodes. Metastatic masses appeared similar to the primary pancreatic mass. Solid and papillary neoplasm of the pancreas should be the primary diagnostic consideration when characteristic CT findings are detected in a young female patient.

Adult↗
PubMed1988

Peripheral cholangiocarcinoma and clonorchiasis: CT findings.

Sixteen patients with peripheral cholangiocarcinoma of the liver were examined with computed tomography (CT). None of the 16 patients presented with jaundice or had documented cirrhosis. On scans obtained both before and after the injection of contrast material, the tumors were depicted as low-attenuation masses in all cases, with wide variations in homogeneity. The tumor margin was irregular in 12 cases, and there was minimal contrast enhancement of the tumor in 14 cases. In 11 (69%) patients, CT demonstrated masses of markedly low attenuation, which corresponded to areas of diffuse microcystic change seen at histologic examination of resected specimens. In ten (63%) patients, the results of stool or intradermal tests for Clonorchis sinensis were positive. In all ten cases of clonorchiasis, mild, diffuse dilatation of the intrahepatic bile ducts was seen in addition to the low-attenuation masses, but there was no dilatation of the extrahepatic biliary tree. In five of the ten patients with clonorchiasis, stippled or aggregated, powderlike areas of high attenuation were seen on precontrast CT scans; at pathologic examination, those areas were found to be mucin. Extrahepatic metastases were demonstrated in ten (63%) patients. Peripheral cholangiocarcinoma should be the primary diagnostic consideration when these characteristic CT findings are detected in a noncirrhotic patient.

Adenoma, Bile Duct↗
PubMed1988

Retained surgical sponge: diagnosis with CT and sonography.

The diagnosis of a retained surgical sponge was made by CT and sonography in four patients. The plain abdominal radiograph was normal in all cases. In each of four cases of gauze granuloma, CT showed a well-defined round mass with a thick wall; internal heterogeneous densities with a wavy, striped, and/or spotted appearance; mottled calcifications; and gas bubbles. Sonography disclosed a well-defined hypoechoic mass containing highly echogenic foci with a strong posterior shadow. In these cases, CT and sonographic findings, together with a history of surgery, permitted the correct preoperative diagnosis of a retained foreign body.

Abdomen↗
PubMed1987

Percutaneous removal of residual intrahepatic stones.

In the Orient there is a high frequency of residual intrahepatic stones after biliary tract surgery. Percutaneous removal of residual intrahepatic stones was attempted in a group of 74 patients. Stones were exclusively intrahepatic in 57 patients, whereas 17 patients also had stones in the common bile duct. Biliary strictures were present in 60 cases (81%). A combination of techniques was used, including preshaped angulated catheters, irrigation-suction, balloon dilation of strictures, and crushing of large stones. In 36 cases all stones were removed and in 14 cases most stones were removed, for a success rate of 67.6%. Biliary stricture was the factor most often responsible for failure.

Adolescent↗