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Biomedical subjects

B I Choi

Publications and source records attributed to B I Choi.

At least 163 records · Page 9Linked to original sources
PubMedDate not supplied

Gastric adenoma with atypical appearance: findings on double-contrast barium study with histopathologic correlation.

BACKGROUND: To describe the radiologic findings of nonpolypoid gastric adenomas and to correlate them with pathologic findings. METHODS: During a 9-year period, we reviewed 49 pure gastric adenomas in 43 patients with positive radiologic findings. Of these adenomas, seven with atypical polypoid appearance were retrospectively included in the study. We reviewed these findings with double-contrast barium study and correlated them with the pathologic findings. RESULTS: Of seven nonpolypoid adenomas, four were depressed and three were flat at pathologic examination. All were diagnosed as early gastric carcinoma (five as type IIc, one as type IIb, one as type IIa + IIc) in upper gastrointestinal series. Three were located in the gastric angle, two in the lower body, and two in the antrum. Size ranged from 10 mm to approximately 25 mm (mean = 15 mm). Six lesions had nodular surface and five had convergency of the mucosal folds. A shallow depressed area was seen in six lesions. CONCLUSIONS: A considerable proportion of gastric adenomas presents as a depressed or flat lesion on double-contrast barium study because of histologic characteristics of decreased subjacent mucosa. Because the nonpolypoid adenoma has a greater potentional for malignancy, more precaution is needed during the follow-up of this uncommon lesion.

Adenoma↗
PubMedDate not supplied

Superselective transcatheter arterial embolization with ethanol and iodized oil for hepatocellular carcinoma.

PURPOSE: The effectiveness of superselective transcatheter arterial embolization with a mixture of ethanol and iodized oil was evaluated for hepatocellular carcinoma. PATIENTS AND METHODS: The procedure was attempted in 14 male patients with hepatocellular carcinoma. The tumor was a single small (2-5 cm in diameter) hypervascular nodule in all patients, except in one patient with two nodules. Superselective catheterization was performed with use of coaxial technique into the third-order branch of the feeding hepatic artery. Under fluoroscopy, 1-4 mL of 75% ethanol mixed with iodized oil was infused. RESULTS: Complete segmental or subsegmental devascularization of the feeding arteries and tumor vascularities occurred in all patients. Follow-up CT or angiography after 9-37 months revealed decrease of tumor in six of nine nonsurgical cases. Subsequent segmentectomy or tumorectomy in five patients revealed total or near-total necrosis of the tumor and thickening of capsules, explaining the halo seen around the tumor on CT scans and the relatively intact surrounding parenchyma seen microscopically. CONCLUSION: Superselective transcatheter arterial embolization with ethanol and iodized oil is a safe method for treatment of small nodular hepatocellular carcinoma with a prominent feeding artery.

Adult↗
PubMedDate not supplied

Transcatheter oily chemoembolization of the inferior phrenic artery in hepatocellular carcinoma: the safety and potential therapeutic role.

PURPOSE: To evaluate the efficacy and safety of transcatheter oily chemoembolization therapy (TOCE) via the inferior phrenic artery (IPA) in hepatocellular carcinoma (HCC). MATERIALS AND METHODS: Fifty patients with HCC underwent a total of 82 procedures of TOCE of the IPA, as well as of the hepatic artery. In 16 patients, additional extrahepatic collaterals were depicted and were also embolized in 10 patients. TOCE was performed with an emulsion of iodized oil and doxorubicin hydrochloride, and gelatin sponge particle embolization was added in 32 patients. RESULTS: Initial response showed complete or partial remission of the tumor in 31 patients. The cumulative survival rates after combined TOCE of the hepatic artery, IPA, and other extrahepatic arteries were 89% (6 months), 78% (1 year), 46% (2 year), and 30% (3 year), when calculated from the time of IPA chemoembolization. Liver abscess and empyema developed in one case of combined IPA and multiple intercostal artery chemoembolization. There were no serious complications after IPA chemoembolization alone. CONCLUSION: TOCE of the IPA has a potential therapeutic role as a safe adjunct to TOCE of the hepatic artery in the management of HCC supplied by the IPA.

Adult↗
PubMedDate not supplied

CT findings of lobar bronchioloalveolar carcinoma.

The CT findings in a case of lobar bronchioloalveolar carcinoma included stretching, spreading, and uniform narrowing of the involved bronchi without obstruction.

Adenocarcinoma, Bronchiolo-Alveolar↗
PubMedDate not supplied

An explanation of renal hemodynamics in acute renal failure based on sequential CT in patients with Korean hemorrhagic fever.

The pattern of renal enhancement and washout of contrast medium was observed on sequential follow-up CT in 12 patients with Korean hemorrhagic fever, in which acute renal failure is one of the most important clinical features. Renal contrast enhancement and contrast medium washout were delayed longer in patients with severe oliguric renal failure. The delayed washout peaked at 4-5 days and did not return to normal until 8-9 days in the patients with severe oliguria; in the patients without severe oliguria the times were 1-2 days and 3-4 days, respectively. A characteristic "cart-wheel" pattern was observed during the washout stage in patients without severe oliguria. This "cart-wheel" pattern of washout is thought to result from relief of vasoconstriction and repair of tubular function. Multifocal "wedge-shaped" nonenhanced areas of the kidney, seen on the 2 week follow-up postcontrast CT, are thought to be ischemic zones due to persistent vasoconstriction. On the 6 week follow-up postcontrast CT in one patient, scarring of the kidney was detected in the same area that did not enhance on the 2 week CT. This scarring is thought to be a result of permanent vasoconstriction.

Acute Kidney Injury↗
PubMedDate not supplied

MR imaging of retroperitoneal teratoma: correlation with CT and pathology.

A retroperitoneal teratoma was studied with CT and magnetic resonance (MR) imaging. The images were correlated with the pathologic findings. The tumor was composed of five portions: adipose tissue, bone, hair, sebum, and loose edematous fibrofatty tissue with skin. Computed tomography and MR both demonstrated a well defined mass with separate cystic and solid components and all five tissue elements of the tumor. Magnetic resonance was superior to CT in delineating the relationship of blood vessels to the tumor.

Adolescent↗
PubMedDate not supplied

Direct invasion of urinary bladder from sigmoid colon cancer: CT findings.

Radiological findings in three cases of sigmoid colon carcinoma invading the urinary bladder are reported. An irregular spiculated margin or nodular indentations in region of bladder dome were seen on intravenous urography. A soft tissue mass contiguous with an irregularly thickened urinary bladder wall and a circumferentially thickened sigmoid colon wall were demonstrated on CT and sonography and led to the correct diagnosis.

Adenocarcinoma↗
PubMedDate not supplied

Preoperative staging of uterine cervical carcinoma: comparison of CT and MRI in 99 patients.

OBJECTIVE: The aim of this study was to compare CT and MRI at 0.5 T in the preoperative staging of uterine cervical cancer in a large series of patients. MATERIALS AND METHODS: Ninety-nine patients with uterine cervical carcinoma underwent CT, MRI, and surgical exploration. RESULTS: Both CT and MR findings were compared using surgical-pathologic findings as gold standards. Magnetic resonance imaging was superior to CT in tumor detection (sensitivity 75 vs. 51%, p < 0.005), in parametrial evaluation (accuracy 87 vs. 80%, p < 0.005), in overall tumor staging (accuracy 77 vs. 69%, p < 0.025), and in pelvic lymph node evaluation (accuracy 88 vs. 83%, p < 0.01). Magnetic resonance imaging had an accuracy of 76% in assessment of the thickness of cervical stromal invasion. CONCLUSION: Magnetic resonance imaging was superior to CT in preoperative staging of uterine cervical carcinoma and MRI should be used instead of CT for preoperative staging of this disease.

Carcinoma↗
PubMedDate not supplied

MR findings of secondary hemochromatosis: transfusional vs erythropoietic.

OBJECTIVE: The aim of this study was to demonstrate the MR characteristics of secondary hemochromatosis (transfusional versus erythropoietic). MATERIALS AND METHODS: Magnetic resonance images of five patients with transfusional (n = 3) or erythropoietic (n = 2) hemochromatosis were reviewed. RESULTS: The liver of all patients had low signal intensity in all pulse sequences. The spleen had low signal intensity in all patients with transfusional iron overload, but normal signal intensity in erythropoietic hemochromatosis, which had similar MR findings to idiopathic hemochromatosis. However, the pancreas had variable signal intensity. CONCLUSION: On MRI the signal intensity of the spleen may allow distinction between transfusional and erythropoietic hemochromatosis.

Adult↗
PubMedDate not supplied

Intraperitoneal drop metastases from hepatocellular carcinoma: CT and angiographic findings.

UNLABELLED: Our goal was to describe the radiological manifestations of intraperitoneal drop metastases (IPDMs) from hepatocellular carcinoma (HCC). METHODS: Seven patients with clinically (n = 4) or pathologically (n = 3) proven IPDMs from HCC were retrospectively analyzed. Medical records, CT scans (n = 7), and angiographic findings (n = 5) were reviewed. RESULTS: On CT scans, all seven patients had single or multiple nodular masses in the liver. In six patients, the hepatic masses showed an exophytic growth. Single (n = 4) or multiple (n = 3) discrete omental masses, 3-10 cm in diameter, were also demonstrated in all patients. Intratumoral necrosis in the omental mass and engorgement of adjacent omental vessels were demonstrated in five and three patients, respectively. On angiography, the omental masses showed hypervascularity supplied by omental branches (n = 4) and superior mesenteric (n = 2) and inferior mesenteric (n = 1) artery and also showed prominent draining veins. CONCLUSION: The radiological manifestations of IPDM from HCC are single or multiple discrete hypervascular masses in the omentum. These are quite different from those of usually carcinomatosis peritonei.

Adult↗
PubMedDate not supplied

Nodular hepatocellular carcinoma: variation of tumor conspicuity on single-level dynamic scan and optimization of fixed delay times for two-phase helical CT.

PURPOSE: The purpose of this work was to determine the optimal delay times in two-phase helical CT for nodular hepatocellular carcinoma (HCC). METHOD: Twenty-four patients with nodular HCC (size 2.1-6.7 cm, mean 4.2 cm) were divided into three groups to undergo single-level dynamic CT with 150 ml of contrast material (iodine load of 45 g) at a rate of 3 ml/s. CT acquisition started 10, 30, or 60 s after the injection for each group, respectively, and lasted for 110 or 120 s. The optimal 20 s windows that allowed a tumor-to-liver contrast of >10 HU were determined in the pooled tumor-to-liver contrast curve. RESULTS: The determined temporal windows were 36-56 and 130-150 s, respectively. However, each window was not appropriate in seven (33%) and five (36%) patients because of the individual variations of the contrast curve. CONCLUSION: There is no optimal fixed delay time that is appropriate in all individual patients. The best delay times are 36 and at least 130 s with our injection protocol.

Adult↗
PubMedDate not supplied

MRI in staging advanced gastric cancer: is it useful compared with spiral CT?

PURPOSE: During the last decade, rapid progress has been made in MR technology. Our objective was to evaluate the role of MRI in staging advanced gastric cancer (AGC; gastric cancer invading the muscularis propria) and to compare it with that of spiral CT. METHOD: We prospectively performed both MR and CT examinations on 26 patients with AGC proven by endoscopic biopsy. Contrast-enhanced CT and nonenhanced MRI with a 1.0 T scanner using FLASH, HASTE, and true-FISP sequences were obtained in each patient after injection of antiperistaltic drug and ingestion of 1 L of tap water. Fifty-two sets of CT and MR images were analyzed by two radiologists in consensus without any information from other images. T and N staging of AGC was determined according to the TNM classification. All patients underwent surgery within 1 week after both examinations. Diagnostic accuracy of each staging of AGC on CT or MRI was evaluated by comparison with the pathologic results. RESULTS: MRI was slightly superior to CT in T staging (81 vs. 73%, respectively; p < 0.05). Although MRI had a tendency to overstage the pathologic T2 cancer, positive predictability of T2 stage and sensitivity of T3 stage were high (100%, respectively). Regarding the N staging, CT was slightly superior to MRI (73 vs. 65%; p > 0.05). However, both CT and MRI demonstrated the tendency of understaging in N staging. CONCLUSION: Although MRI was superior to spiral CT in T staging, MRI cannot completely replace spiral CT in staging AGC because of its limitation in N staging.

Adult↗
PubMedDate not supplied

Factors influencing vascular and hepatic enhancement at CT: experimental study on injection protocol using a canine model.

PURPOSE: The purpose of this work was to evaluate the effects of contrast medium injection parameters on aortic, portal vein, and hepatic enhancement at spiral CT and to assess optimal injection protocol for hepatic CT. METHOD: Ten 15 kg dogs underwent single level dynamic CT through the hepatic hilum at 5 s intervals just after the injection of contrast medium for 3 min. With use of different volumes (1, 2, and 3 ml/kg), injection rates (0.5, 1, and 2 ml/s), and concentrations (150, 200, and 300 mg/ml), a total of 270 spiral CT scans were performed. In each scan, time-attenuation curves of aorta, portal vein, and liver were obtained. The degree of maximum contrast enhancement (Imax), time to maximum enhancement (Tmax), and time to equilibrium phase (Teq) for to each injection protocol were analyzed. RESULTS: Alterations in contrast material volume, injection rate, and concentration had significant impact on contrast enhancement of the liver. With increasing volume of contrast medium, Imax, Tmax, and Teq of aorta, portal vein, and liver increased (p < 0.005). With increasing rate of injection, on the other hand, Imax of aorta and liver increased (p < 0.05), but Tmax and Teq decreased (p < 0.005). Change of concentration of contrast medium had a significant effect on Imax of vessels (p < 0.05). CONCLUSION: Maximum contrast enhancement of liver and vessels was influenced mainly by injection volume of contrast medium and the time to peak enhancement by injection rate of contrast medium. Under given amounts of contrast medium, therefore, the strategy of increasing volume by dilution and faster injection might give better Imax values without penalty for the duration of an optimal temporal window (Tmax and Teq).

Animals↗
PubMedDate not supplied

Fat replacement with absence of acinar and ductal structure in the pancreatic body and tail.

We report an unusual case of fat replacement of the pancreatic body and tail. Findings on contrast-enhanced computed tomography and ERCP could be confused with dorsal pancreas agenesis. Histopathologic examination of the resected specimen revealed massive fat replacement with complete absence of the acinar and ductal tissue and scattered islets of Langerhans.

Adipose Tissue↗
PubMedDate not supplied

Castleman disease of the abdomen: imaging spectrum and clinicopathologic correlations.

PURPOSE: The purpose of this work was to define the imaging spectrum of Castleman disease of the abdomen and to correlate the results with clinicopathologic findings. METHOD: Seventeen patients (male/female 7:10; mean age 35.6 years) with pathologically proved Castleman disease in the abdomen were included in this study. Radiologic findings (CT, n =17; US, n =10; MR, n =1) were retrospectively reviewed by two readers and were correlated with clinical and pathologic findings. RESULTS: Subjects were divided into those with localized (n = 11) and disseminated (n = 6) disease. In localized disease, the pathologic subtypes were hyaline vascular type in eight and plasma cell type in three. Radiologic studies showed a single large mass in six and a single dominant mass with small satellite nodules in five. Central low attenuation was seen in two cases, and calcification was seen in three cases. Regional lymphadenopathy was found in five cases. In disseminated disease, there were three hyaline vascular types and three plasma cell types. Radiologic findings included diffuse lymphadenopathy (n = 6), hepatosplenomegaly (n = 5), ascites (n = 3), and thickening of the retroperitoneal fascia (n = 3). Disseminated disease revealed symptoms and abnormal laboratory findings (anemia, hypoalbuminemia, elevated erythrocyte sedimentation rate/C-reactive protein, etc.) more frequently than localized disease and showed poor prognosis. CONCLUSION: There are two distinctive types of radiologic manifestations in Castleman disease of the abdomen: localized and disseminated. The localized type usually shows single or multiple discrete masses, and the disseminated type frequently shows nonspecific organomegaly and lymphadenopathy.

Abdomen↗