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Hyo-Cheol Kim

Publications and source records attributed to Hyo-Cheol Kim.

At least 19 recordsLinked to original sources
PubMed2007

Internal mammary arteries supplying hepatocellular carcinoma: vascular anatomy at digital subtraction angiography in 97 patients.

PURPOSE: To retrospectively evaluate the vascular anatomy of the internal mammary arteries that supply hepatocellular carcinomas (HCCs), with an emphasis on number of tumor feeders. MATERIALS AND METHODS: This retrospective study was approved by the institutional review board; informed consent was waived. Between August 1996 and July 2005, internal mammary arteries that supply HCCs were found in 97 (2.2%) of 4438 patients (76 men, 21 women; mean age, 55 years +/- 10.5 [standard deviation]; range, 19-79 years). Computed tomographic scans and digital subtraction angiograms in these 97 patients were retrospectively reviewed in consensus by two interventional radiologists. Tumor size, number of tumor feeders, and tumor location were recorded. The t test and analysis of variance were used to correlate tumor size with number of tumor feeders, tumor feeder laterality, and transcatheter arterial chemoembolization (TACE) time. RESULTS: The following 125 tumor feeders were identified in 97 patients: phrenic branch (n = 59), musculophrenic artery (n = 40), superior epigastric artery (n = 15), anterior intercostal artery (n = 6), ensiform artery (n = 4), and pericardiacophrenic artery (n = 1). In two patients, tumors were in dorsal hepatic areas directly beneath the diaphragm. Half of the tumors located in liver segments II or III were supplied by the right internal mammary artery. In three patients, the tumor feeders from the left internal mammary artery crossed the midline. Tumor size was not statistically associated with number of tumor feeders (P = .076), tumor feeder laterality (P = .141), and TACE time (P = .729). CONCLUSION: The common tumor feeders of the internal mammary artery are the phrenic branch and the musculophrenic artery. Moreover, the internal mammary artery can supply a tumor even in the dorsal hepatic area.

Adult↗
PubMed2006

Hepatocellular carcinoma: transcatheter arterial chemoembolization of the gonadal artery.

Over the past 9 years, the authors have identified gonadal arteries supplying hepatocellular carcinoma in seven of 4,438 patients (0.16%) whom they attempted to treat by transcatheter arterial chemoembolization. All seven patients had tumors in the Couinaud segment 6 (S6) of the liver (mean size, 6.8 cm). The gonadal arteries in all seven patients showed anatomic variations, including a high origin (n = 3) and a common trunk with the adrenal artery (n = 4). The gonadal artery with anatomic variation may supply hepatocellular carcinomas located in liver S6.

Adult↗
PubMed2006

Unusual malignant tumors of the gallbladder.

OBJECTIVE: The purpose of this pictorial essay is to review the spectrum of unusual malignant tumors of the gallbladder and to illustrate their radiologic features. CONCLUSION: Radiologic findings of unusual malignant gallbladder tumors are varied and overlap with those of ordinary gallbladder carcinoma. Despite their rarity, being familiar with the wide spectrum of radiologic findings of these unusual tumors is helpful to improve diagnostic accuracy.

Adult↗
PubMed2005

Fluoroscopically guided balloon dilation for benign anastomotic stricture after Ivor-Lewis esophagectomy: experience in 62 patients.

PURPOSE: To evaluate the safety and clinical effectiveness of fluoroscopically guided balloon dilation in 62 patients with benign anastomotic stricture after Ivor-Lewis esophagectomy. MATERIALS AND METHODS: Between January 1996 and June 2004, fluoroscopically guided balloon dilation was undertaken in 62 patients with benign anastomotic stricture after Ivor-Lewis esophagectomy. Radiologic images and medical records including complications were retrospectively reviewed. The maximum diameters of the balloon catheters used were 18-20 mm. Clinical success was defined by the absence of recurrent dysphagia after balloon dilation until the most recent follow-up. The Fisher exact test was used to assess the relationship of symptomatic recurrence and the balloon size, width of the stricture, and radiation therapy. RESULTS: There were 115 sessions of balloon dilation in 62 patients (mean, 1.85 sessions per patient). Clinical success was achieved in 59 patients (95%) by means of a single dilation (n = 29) or by multiple dilations (n = 30). One patient with severe stenosis was successfully treated with temporary placement of a covered retrievable stent. Major complications such as esophageal perforation or massive bleeding did not occur. Four patients with mucosal tear (n = 3) or aspiration pneumonia (n = 1) were conservatively treated. Patients with severe stricture had more symptomatic recurrences than those with moderate stricture. CONCLUSION: Fluoroscopically guided balloon dilation is a safe and successful treatment modality for benign anastomotic stricture after Ivor-Lewis esophagectomy.

Adult↗
PubMed2005

Recognizing extrahepatic collateral vessels that supply hepatocellular carcinoma to avoid complications of transcatheter arterial chemoembolization.

Extrahepatic collateral arteries commonly supply hepatocellular carcinomas if the tumors are large or peripherally located. Because development of these vessels interferes with effective control of the tumor with transcatheter arterial chemoembolization (TACE), radiologists should become familiar with the imaging findings of extrahepatic collateral vessels to detect them at an early stage. The authors observed 2104 such vessels in 860 patients over 5.5 years. The extrahepatic collateral vessels observed originated from the inferior phrenic artery, omental branch, adrenal artery, intercostal artery, cystic artery, internal mammary artery, renal or renal capsular artery, branch of the superior mesenteric artery, gastric artery, and lumbar artery. The authors suspected extrahepatic collateral vessels when (a) a tumor grew exophytically or invaded adjacent organs, (b) a tumor was in contact with the ligaments and bare area of the liver, (c) a hypertrophied extrahepatic collateral vessel was observed on a computed tomographic (CT) scan, (d) a peripheral defect of iodized oil retention within a tumor was seen during chemoembolization or on a follow-up CT scan, (e) a local recurrence developed at the peripheral portion of the treated tumor during follow-up, or (f) a sustained elevation in serum alpha-fetoprotein level was noted despite adequate embolization of the hepatic artery. When both the hepatic artery and extrahepatic collateral vessels supply a tumor, additional extrahepatic collateral vessel chemoembolization should be attempted to increase the therapeutic efficacy of TACE for hepatocellular carcinoma.

Adult↗
PubMed2004

Acute iliofemoral deep vein thrombosis: evaluation of underlying anatomic abnormalities by spiral CT venography.

PURPOSE: To evaluate the spectrum of underlying anatomic abnormalities in iliofemoral deep vein thrombosis (DVT) by spiral computed tomographic (CT) venography. MATERIALS AND METHODS: During the past 4 years, 56 patients with acute iliofemoral DVT have been evaluated by CT venography at our institution. Forty-four patients had left-sided DVT, nine had right-sided DVT, and the remaining three had DVT in both extremities. CT venography was performed with use of 2.5-3.2-mm x-ray beam collimation and a 1.25-2.0-mm reconstruction interval. Spiral scans were initiated 5 minutes after intravenous contrast medium injection. The CT venograms were correlated with catheter venograms. In addition, with use of axial sections and their three-dimensional reconstructions, including multiplanar reformation and volume rendering, the presence or absence of central obstructing lesions and their causes were evaluated. RESULTS: Among 44 patients with left-sided DVT, 37 had significant anatomic abnormalities in their iliofemoral veins or inferior vena cava (IVC). The most common lesion was left common iliac vein compression by the right common iliac artery (n = 27; exaggerated by a bony spur in nine and associated with extrinsic compression by the left internal iliac artery in two). Of the nine patients with right-sided DVT, six had significant anatomic abnormalities including encasement or extrinsic compression of their iliac veins by various causes (n = 3) and venous stricture without extrinsic lesions (n = 3). Among three patients with DVT in both extremities, two had anatomic abnormalities in the IVC. Therefore, 45 of 56 patients had anatomic abnormalities central to the thrombosed deep veins. CONCLUSION: The majority of patients with acute iliofemoral DVT had underlying anatomic abnormalities. The presence of central stenosis or obstruction and their causes can be evaluated by spiral CT venography.

Adolescent↗
PubMed2004

Primary gastrointestinal stromal tumors in the omentum and mesentery: CT findings and pathologic correlations.

OBJECTIVE: This study was undertaken to describe the CT features of primary gastrointestinal stromal tumors in the omentum and mesentery and to identify any pathologic correlation. CONCLUSION: On contrast-enhanced CT, primary gastrointestinal stromal tumors in the omentum and mesentery are usually well-defined, huge masses that contain large areas of low-attenuation necrosis and hemorrhage and that lack central gas.

Adult↗
PubMed2004

Gastrointestinal stromal tumors of the duodenum: CT and barium study findings.

OBJECTIVE: The purpose of this study was to describe the CT and radiographic features of gastrointestinal stromal tumors of the duodenum. CONCLUSION: Gastrointestinal stromal tumors of the duodenum appear on barium studies as extrinsically compressing or submucosal masses with or without ulceration. These tumors usually appear on contrast-enhanced CT as well-defined masses with an exoenteric growth pattern and relatively good heterogeneous enhancement.

Adult↗
PubMed2004

Gastrointestinal stromal tumors of the stomach: CT findings and prediction of malignancy.

OBJECTIVE: The purpose of this study was to identify predictors of malignancy on CT for the evaluation of gastrointestinal stromal tumors of the stomach. MATERIALS AND METHODS: The medical records at our institution of 81 patients with a histologic diagnosis of gastrointestinal stromal tumor of the stomach were reviewed. Two radiologists retrospectively reviewed the CT findings by consensus with respect to lesion size, contour, tumor growth pattern, enhancing pattern, degree of enhancement, mesenteric fat infiltration, ulceration, calcification, lymphadenopathy, direct invasion to adjacent organ, and distant metastasis. Categoric variables were compared using the chi-square or Fisher's exact test. Multiple stepwise logistic regression analysis by means of forward selection was performed to determine significant predictors of high mitotic rate. Univariate analysis and multivariate analysis were also performed in a subgroup of 36 tumors with maximal diameter of 5 cm or smaller. RESULTS: Size, presence of an ulcer, mesenteric fat infiltration, direct organ invasion, and metastasis were more frequently observed during univariate analysis in tumors with a high mitotic rate (p < 0.05). With stepwise logistic regression analysis, the size (odds ratio, 2.57; 95% CI; 1.42-4.67) was the only significant predictor of a high mitotic rate. In a subgroup of 36 tumors 5 cm or smaller, differentiation of benign from malignant tumors was not possible using CT. CONCLUSION: Although presence of an ulcer, mesenteric fat infiltration, direct organ invasion, and metastasis were more frequently observed in tumors with a high mitotic rate, no CT feature, other than size, was found to have predictive value with respect to malignant gastrointestinal stromal tumors of the stomach.

Adult↗
PubMed2003

Primary thyroid lymphoma: CT findings.

INTRODUCTION: To evaluate the computed tomographic (CT) findings of primary thyroid lymphoma. METHODS AND MATERIAL: The clinicopathological data and CT images of nine patients with primary thyroid lymphoma were retrospectively reviewed. The CT appearances were classified into three types: type 1, a solitary nodule surrounded by normal thyroid tissue; type 2, multiple nodules in the thyroid, and type 3, a homogeneously enlarged both thyroid glands with a reduced attenuation with or without peripheral thin hyperattenuating thyroid tissue. RESULTS: All patients had a rapidly enlarging thyroid mass and coexistent Hashimoto's thyroiditis. One patient showed type 1 pattern, three type 2, and five type 3. Six patients had homogeneous tumor isoattenuating to surrounding muscles. The tumors had a strong tendency to compress normal remnant thyroid and the surrounding structure without invasion. CONCLUSION: Primary thyroid lymphoma should be included in the differential diagnosis when old female had a homogeneous thyroidal mass isoattenuating to muscles, which does not invade surrounding structures.

Aged↗
PubMed2003

Hepatocellular carcinoma: assessment of vascularity with single-level dynamic ultrasonography during the arterial phase.

OBJECTIVE: To evaluate the hemodynamic features of hepatocellular carcinoma on single-level dynamic ultrasonography during the arterial phase. METHODS: Twenty-two hepatocellular carcinomas were examined by single-level dynamic ultrasonography with high transmit intensity and SH U 508A. The scans were performed for 40 seconds with a 1-second interval between each ultrasound transmission and with individual optimization of the scan delay time. The times of initiation of enhancement for both the hepatic artery and the tumor and the time of maximal enhancement for the tumor were recorded, and the mean echo values at every second for the tumor and hepatic parenchyma were measured. RESULTS: Twelve tumors showed hyperechoic enhancement compared with hepatic parenchyma throughout the scans. The other 10 showed hyperechoic enhancement during some segments (range, 8-34 seconds) and either isoechoic (n = 5) or hypoechoic (n = 5) enhancement during the remaining parts; the hyperechoic segments were often short (< 20 seconds, 14%). Although the times for initiation of enhancement for the hepatic artery and hepatocellular carcinoma and the time of maximal enhancement for the tumor varied, the tumor usually initiated enhancement immediately after the hepatic artery (r = 0.986; P = .000001). The interval between the time of initiation of enhancement for the tumor or hepatic artery and that of maximal enhancement for the tumor was significantly correlated with the tumor size (r = 0.700; P = .008; and r = 0.780; P = .002). CONCLUSIONS: With individual optimization of the scan delay time, single-level dynamic ultrasonography is useful for depicting the hypervascularity of hepatocellular carcinoma during the arterial phase.

Adult↗
PubMed2003

Delayed encephalopathy of acute carbon monoxide intoxication: diffusivity of cerebral white matter lesions.

BACKGROUND AND PURPOSE: Carbon monoxide intoxication has delayed effects on the cerebral white matter characterized by bilateral, confluent lesions that reflect diffuse demyelination. To increase our understanding of this process, we assessed the diffusion characteristics of these lesions. METHODS: Five consecutive patients with delayed encephalopathy of CO intoxication were examined with diffusion MR imaging. Diffusion-weighted images (DWIs) were obtained 25-95 days after their exposure to CO and during a relapse of neuropsychiatric symptoms, which occurred after an initial recovery. Imaging was performed at 1.5 T by using a spin-echo echo-planar sequence with diffusion gradients of 0, 500, and 1000 s/mm(2). DWIs and apparent diffusion coefficient (ADC) maps were visually evaluated, and mean ADCs were calculated from the periventricular white matter and the centrum semiovale, where confluent hyperintensity was seen on T2-weighted images. Findings were compared with those of normal-looking white matter. RESULTS: In all five patients, both T2-weighted images and DWIs showed the white matter lesions as bilateral, diffuse, confluent areas of hyperintensity in the periventricular white matter and centrum semiovale. On ADC maps, these lesions were isointense, with focal areas of hypointensity (n = 4) or diffuse hypointensity (n = 1). Mean ADC values of the white matter lesions were significantly lower than those of normal-looking white matter, regardless of their isointensity or hypointensity on ADC maps (P <.05). CONCLUSION: Bilateral, confluent, white matter lesions in patients with delayed encephalopathy of CO intoxication show decreased diffusivity.

Aged↗
PubMed2002

Tuberculosis in patients with myelodysplastic syndromes.

AIM: The purpose of our study was to describe radiological manifestations of tuberculosis in patients with myelodysplastic syndromes. MATERIALS AND METHODS: Chest radiographs and CTs of 12 patients with tuberculosis among 195 consecutive patients with myelodysplastic syndrome, proved by bone marrow biopsy, were reviewed. Six of the 12 patients presented with tuberculosis and were subsequently found to have myelodysplastic syndrome. RESULTS: Chest radiographs and CTs revealed pulmonary tuberculosis in all 12 patients and extrapulmonary tuberculous involvement in six (50%). Initial chest radiographic findings of pulmonary tuberculosis included a primary pattern (n = 6), a post-primary pattern (n = 3), a miliary pattern (n = 1), atypical infiltrates (n = 1) and normal radiograph (n = 1). Tuberculosis involved extrathoracic lymph nodes (n = 5), liver (n = 2), spleen (n = 2), kidney (n = 2), bowel (n = 2), pericardium (n = 2) peritoneum (n = 1) and rib (n = 1). CONCLUSION: Tuberculosis is a relatively common cause of infection in patients with myelodysplastic syndromes. The radiological appearance of pulmonary tuberculosis in myelodysplastic syndromes is often a primary pattern, and there is frequently extrapulmonary involvement.

Adult↗
PubMed2002

Hepatic arterial and portal venous phase helical CT in patients treated with transcatheter arterial chemoembolization for hepatocellular carcinoma: added value of unenhanced images.

PURPOSE: To evaluate the additional diagnostic value of unenhanced computed tomographic (CT) images in the depiction of viable tumor in patients who were treated with transcatheter arterial chemoembolization (TACE) for hepatocellular carcinoma (HCC) and followed up with biphasic helical CT that included the acquisition of unenhanced images. MATERIALS AND METHODS: We performed helical CT (with unenhanced, arterial, and portal phases) in 54 patients who had been treated with TACE for HCC. Image analysis was first performed with only those images obtained in the arterial and portal venous phases of helical CT. A second analysis was then performed with unenhanced images, arterial images, and portal venous images that focused on the additional value of unenhanced images. The value of additional unenhanced images was evaluated by means of interobserver agreement (kappa statistic) and receiver operating characteristic (ROC) analysis. RESULTS: The two readers detected 128 and 129 lesions. Unenhanced images were valuable for 32 of 129 lesions (23 patients) for reader 1 and for 29 of 128 lesions (21 patients) for reader 2. Although there was no significant difference between biphasic CT alone and biphasic CT with unenhanced images, results of ROC analysis showed higher diagnostic performance with biphasic CT with unenhanced images than with biphasic CT alone for detecting viable tumor. CONCLUSION: The study data demonstrate the diagnostic value of unenhanced images interpreted in conjunction with biphasic CT images for follow-up of patients who have previously been treated with TACE for HCC.

Carcinoma, Hepatocellular↗
PubMedDate not supplied

Subependymoma in the third ventricle in a child.

Subependymomas are rare, slow-growing, benign intraventricular tumors which occur commonly in the fourth or lateral ventricle. They usually occur in elderly men and often are asymptomatic and discovered incidentally. We report a case of a 6-year-old girl with a symptomatic subependymoma in the third ventricle with MR imaging.

Age Factors↗
PubMedDate not supplied

Collateral pathways in thoracic central venous obstruction: three-dimensional display using direct spiral computed tomography venography.

We illustrate the spectrum of venous collateral pathways caused by the thoracic central venous obstruction with direct spiral computed tomography (CT) venography and 3-dimensional reconstruction images. Venous structures that can be demonstrated with CT venography include the jugular veins; the subclavian and brachiocephalic (innominate) veins; the internal and lateral thoracic veins; the superior and inferior venae cavae; the pericardiophrenic veins; the azygos, hemiazygos, and accessory hemiazygos veins; and the intercostal veins.

Adult↗
PubMedDate not supplied

Multidrug-resistant tuberculosis versus drug-sensitive tuberculosis in human immunodeficiency virus-negative patients: computed tomography features.

OBJECTIVES: To compare the computed tomography (CT) features of patients with multidrug-resistant tuberculosis with those of patients with drug-sensitive tuberculosis in a country not associated with the human immunodeficiency virus (HIV) epidemic. METHODS: The CT images of 47 patients with multidrug-resistant tuberculosis were compared with those of 47 patients with drug-sensitive tuberculosis as a control group. Each multidrug-resistant tuberculosis patient was age (decade) and gender matched to a drug-sensitive tuberculosis patient. All patients were seronegative to HIV. This study evaluated the presence of centrilobular nodules, consolidation, emphysema, bronchiectasis, lung destruction, calcified granuloma, cavitation, pleural effusion, and lymphadenopathy. A statistical comparison was performed by using the Fisher exact test for univariate analysis and a multiple logistic regression method for multivariate analysis. RESULTS: In univariate analysis, bronchiectasis, lung destruction, a calcified granuloma, and cavitation were more frequently observed in multidrug-resistant tuberculosis than in drug-sensitive tuberculosis. Multivariate analysis showed that cavity formation was the only significant difference between multidrug-resistant tuberculosis and drug-sensitive tuberculosis. In patients with cavitary tuberculosis, multiple cavities (>3 cavities) were observed only in patients with multidrug-resistant tuberculosis. CONCLUSIONS: Most patients with multidrug-resistant tuberculosis had cavity formation on CT. Although the presence of a cavity does not mean multidrug resistance, multiple cavities suggest the possibility of multidrug-resistant tuberculosis.

Adolescent↗