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Hyo Keun Lim

Publications and source records attributed to Hyo Keun Lim.

At least 19 recordsLinked to original sources
PubMed2006

Encapsulated hepatocellular carcinoma: CT-pathologic correlations.

This study is a retrospective evaluation of the correlations between the presence and integrity of the capsule of nodular hepatocellular carcinomas (HCC) by dynamic CT and histopathology, with histopathologic evidence of tumor propagation to surrounding hepatic parenchyma. Dynamic CT scans of 75 nodular HCCs in 73 patients (61 men, 12 women; age range, 32-81; mean, 53) were evaluated regarding capsule visualization and integrity. Histopathologic findings of HCCs in resected specimens were correlated with the presence of a capsule, tumor invasion onto the capsule, and with the presence of microvascular emboli in the surrounding liver parenchyma. On histopathologic examination, capsules were present in 57 of 75 nodular HCCs; the capsules were invaded by tumor in 18 nodules and there were microvascular emboli around the nodular HCC in 49 cases. Capsule visualization by CT was correlated with the presence of capsule by histopathology (P<0.001). Disruption of capsule by CT was correlated with tumor invasion by histopathology (P=0.003) and with microvascular tumor emboli (P<0.001). The presence and structural integrity of HCC capsules on CT was closely correlated with the presence of capsule on histopathology and the absence of microvascular tumor emboli.

Adult↗
PubMed2006

Preoperative staging of rectal cancer: accuracy of 3-Tesla magnetic resonance imaging.

The purpose of this study was to evaluate the accuracy of 3-Tesla magnetic resonance imaging (MRI) for the preoperative staging of rectal cancer. Thirty-five patients with a primary rectal cancer who underwent preoperative 3-T MRI using a phased-array coil and had a surgical resection were enrolled in the study group. Preoperatively, three experienced radiologists independently assessed the T and N staging. A confidence level scoring system was used to determine if there was any perirectal invasion, and receiver operating characteristic (ROC) curves were generated. The interobserver agreement was estimated using kappa statistics. The overall accuracy rate of T staging for rectal cancer was 92%. The diagnostic accuracy was 97% for T1, 89% for T2 and 91% for T3, respectively. The predictive accuracy for perirectal invasion by the three observers was high (Az>0.92). The interobserver agreement for T staging was moderate to substantial. The overall sensitivity, specificity, and accuracy for the detection of mesorectal nodal metastases were 80%, 98%, and 95%, respectively. In conclusion, preoperative 3-T MRI using a phase-array coil accurately indicates the depth of tumor invasion for rectal cancer with a low variability.

Adenocarcinoma↗
PubMed2006

Early bile duct carcinoma: comparison of imaging features with pathologic findings.

PURPOSE: To retrospectively evaluate the imaging features of early bile duct carcinoma and to compare these features with histopathologic findings. MATERIALS AND METHODS: The institutional review board did not require its approval or informed patient consent for this study. Twenty-one patients (13 men, eight women; mean age, 60 years; range, 48-75 years) with early bile duct carcinoma that was surgically resected and histopathologically confirmed were included. Ultrasonography (US) was performed in 15 patients, computed tomography (CT) in 21, cholangiography in 18, and magnetic resonance (MR) cholangiography in six. Two radiologists retrospectively reviewed imaging features by consensus; they compared growth pattern of tumors, integrity of the bile duct wall that harbored the tumor, and periductal infiltration with histopathologic findings. RESULTS: Pathologic specimens showed intraluminal tumor growth in all cases. Tumors were confined to the mucosa in 11 patients and involved the fibromuscular layer in 10 patients. In four of the 10 intrahepatic cholangiocarcinomas, four of the five hilar cholangiocarcinomas, and six of the six extrahepatic cholangiocarcinomas, there were intraductal tumor masses and the wall of the tumor-bearing bile ducts was preserved without periductal infiltration on US and CT images. On cholangiograms and MR cholangiograms, tumors were better delineated but the wall invasion could not be evaluated. No difference in image findings was found between carcinoma confined to the mucosa and carcinoma involving the fibromuscular layer. CONCLUSION: Imaging features of early bile duct carcinoma are a tumor mass in the bile duct lumen and integrity of the tumor-bearing bile duct wall without infiltration outside the wall.

Adenocarcinoma↗
PubMed2006

Primary Budd-Chiari syndrome: outcome of endovascular management for suprahepatic venous obstruction.

OBJECTIVE: Primary Budd-Chiari syndrome (BCS) is a rare form of hepatic venous outflow obstruction at the suprahepatic inferior vena cava (IVC), the hepatic veins, or both. We assessed our 4-year experience in the management of BCS to evaluate the results of our methods of care. METHODS: We conducted a retrospective review of a nonrandomized clinical trial conducted in three teaching hospitals. Among 28 primary BCS patients, 9 remained in medical treatment only, and 19 who failed to respond to medical treatment received additional endovascular (n = 17) or surgical therapy (n = 2). Nine underwent IVC balloon angioplasty alone, 6 had angioplasty plus stents, and 2 had transjugular intrahepatic portosystemic shunts (TIPS) for hepatic vein lesions. One patient had a mesoatrial bypass; another had liver transplantation. Immediate response to the therapy was assessed with angiography and ultrasonography based on anatomic and/or hemodynamic correction or reduction of the lesion. Subsequent assessment of portal hypertension status was made with periodic clinical and laboratory evaluation (eg, ultrasonography, liver biopsy). RESULTS: Twenty-six patients had had IVC stenosis or occlusion by focal or segmental lesion. Two patients had hepatic vein outlet obstruction. There was no evidence of coagulopathy as the pathogenesis; all were related to membranous obstruction of the vena cava. Excellent immediate response to the endovascular therapy and subsequent relief of portal hypertension were achieved in 14 patients. Four patients had restenosis or progression of the residual lesion within 2 years; three responded to repeated stenting. Primary patency was 76.5%, and primary assisted patency was 94.1%. Two patients with TIPS and two with surgical therapy maintained excellent results. The medical treatment remained effective only in a limited group of 6 (21.4%) of the 28 patients. CONCLUSIONS: In BCS, both endovascular and surgical interventions provide excellent results and potentially halt liver parenchymal deterioration caused by portal hypertension. Liver transplantation remains the ultimate solution for advanced liver failure.

Adult↗
PubMed2006

Percutaneous radiofrequency ablation therapy of hepatocellular carcinoma using multitined expandable electrodes: comparison of subcapsular and nonsubcapsular tumors.

OBJECTIVE: Our objective was to compare the prognosis of subcapsular and nonsubcapsular hepatocellular carcinoma after percutaneous radiofrequency ablation using multitined expandable electrodes. MATERIALS AND METHODS: Some controversies exist about the clinical usefulness of percutaneous radiofrequency ablation of subcapsular hepatocellular carcinoma. Twenty-eight patients underwent percutaneous radiofrequency ablation of 43 hepatocellular carcinomas using multitined expandable electrodes. Twelve tumors were subcapsular and 31 were nonsubcapsular. We attempted to use normal liver as a pathway to the tumor when possible. Tumor size ranged from 1.0 to 4.2 cm (mean, 1.8 cm). Median follow-up was 16 months. Initial ablation was considered to have been complete when no enhancement was seen in the region of the ablated lesion on 1-month follow-up CT or on follow-up CT performed immediately after repeated ablation. Initial complete ablation and local tumor progression rates were compared between subcapsular and nonsubcapsular tumors. Eleven patients had subcapsular tumors (group 1), whereas the other 17 patients did not have subcapsular tumors (group 2). Major complication and mortality rates were compared between the two groups. RESULTS: No significant differences in initial complete ablation rate (100% vs 96.7%, p = 1.000) or local tumor progression rate (0% vs 10.0%, p = 0.545) were found between subcapsular and nonsubcapsular tumors. No procedure-related major complication or mortality occurred. The overall 1- and 3-year survival rates were 89.3% and 60.3%, respectively. CONCLUSION: The rates of local tumor progression and complications for radiofrequency ablation using multitined expandable electrodes for subcapsular hepatocellular carcinomas were comparable to those for nonsubcapsular hepatocellular carcinomas.

Aged↗
PubMed2006

A case of needle tract implantation of hepatocellular carcinoma after percutaneous biopsy with an 18G Tru-cut needle.

Needle tract implantation of hepatocellular carcinoma (HCC) is a rare complication of percutaneous biopsy, and it is largely associated with end-cutting needles or aspiration biopsy. The CT findings that have been reported include oval or round soft tissue nodules with persistent contrast enhancement along the needle tract, mostly in the subcutaneous tissue or the intercostal muscle layers. In this report, we describe a case of needle tract implantation of HCC after US-guided percutaneous biopsy with an 18G tru-cut needle.

Adult↗
PubMed2005

Comparing the outcomes of radiofrequency ablation and surgery in patients with a single small hepatocellular carcinoma and well-preserved hepatic function.

GOALS: To compare the efficacy of radiofrequency ablation (RFA) and surgical resection in a group of patients with a Child-Pugh score of 5 and a single HCC less than 4 cm in diameter. BACKGROUND: Radiofrequency ablation (RFA) has become a popular method for treatment of hepatocellular carcinoma (HCC) and has been applied as an alternative primary therapy to surgical resection. STUDY: We compared outcomes for 148 patients treated with RFA (n = 55) and those treated surgically (n = 93). RESULTS: The rate of local recurrence among patients in the RFA group was significantly higher than in the surgery group (P = 0.005), while the incidence of remote recurrence was similar between the two groups (P = 0.30). The cumulative 1- and 3-year overall survival rates (P = 0.24) and the cumulative 1- and 3-year recurrence-free survival rates (P = 0.54) were not significantly different between the two groups. CONCLUSIONS: Despite a higher rate of local recurrence, RFA was found to be as effective as surgical resection for the treatment of single small HCC in patients with well-preserved liver function, in terms of the incidence of remote recurrence and the patients' likelihood of achieving overall and/or recurrence-free survival.

Carcinoma, Hepatocellular↗
PubMed2005

Neoangiogenesis and sinusoidal capillarization in hepatocellular carcinoma: correlation between dynamic CT and density of tumor microvessels.

PURPOSE: To retrospectively evaluate the correlation between the degree of contrast enhancement on dynamic computed tomographic (CT) scans and the degree of neoangiogenesis and sinusoidal capillarization in hepatocellular carcinoma (HCC). MATERIALS AND METHODS: The institutional review board did not require approval or informed patient's consent for the review of medical records or images. Dynamic CT scans of 97 nodular HCCs in 97 patients (79 men, 18 women; age range, 29-73 years; mean age, 54 years) were evaluated in terms of the attenuation change in the arterial, portal venous, and delayed phases, and the results were correlated with the number of unpaired arteries and the degree of sinusoidal capillarization at histopathologic examination. The mean attenuation value of the nodular HCCs on triple-phase helical CT scans was correlated with the number of unpaired arteries and the degree of sinusoidal capillarization. Statistical analysis was performed with the Spearman rank correlation test. RESULTS: The number of unpaired arteries in the nodular HCCs was found to correlate with the degree of contrast enhancement in the arterial phase (r = 0.225, P = .027), but did not correlate with the degree of contrast enhancement in the portal and delayed phases. The degree of sinusoidal capillarization did not correlate linearly with the mean attenuation of the nodular HCCs in any phase of contrast enhancement. CONCLUSION: The degree of contrast enhancement of the nodular HCCs in the arterial phase tended to correlate with the number of unpaired arteries, but no correlation was evident between the degree of contrast enhancement and sinusoidal capillarization in any phase of CT imaging.

Adult↗
PubMed2003

Poor sensitivity of sonography in detection of hepatocellular carcinoma in advanced liver cirrhosis: accuracy of pretransplantation sonography in 118 patients.

The objective of this study was to assess the detectability of hepatocellular carcinoma by sonography in advanced cirrhotic patients undergoing liver transplantation. We retrospectively reviewed pretransplantation sonography in 118 consecutive patients with advanced liver cirrhosis. We assessed the detectability of hepatocellular carcinoma in relation to tumor size, location, total liver volume, and degree of sonographic heterogeneity of the liver parenchyma. On pathologic examination, 51 hepatocellular carcinomas were identified in 31 patients. Pretransplantation sonography depicted 14 of 51 (27%) hepatocellular carcinomas. Detectability was significantly affected according to tumor size ( p=0.0099), but there was no significant difference according to tumor location, liver volume, or degree of sonographic heterogeneity of the liver parenchyma. Our study suggests that sonography is not sufficiently sensitive to detect hepatocellular carcinoma in patients with advanced liver cirrhosis. Tumor size is the only factor influencing the detectability of hepatocellular carcinoma.

Carcinoma, Hepatocellular↗
PubMed2003

Preoperative depiction of hepatocellular carcinoma: ferumoxides-enhanced MR imaging versus triple-phase helical CT.

PURPOSE: To compare ferumoxides-enhanced magnetic resonance (MR) imaging with triple-phase helical computed tomography (CT) for the preoperative depiction of hepatocellular carcinoma (HCC). MATERIALS AND METHODS: Seventy consecutive patients with a total of 79 HCC nodules underwent ferumoxides-enhanced MR imaging and triple-phase helical CT before surgery. The diagnosis of HCC was established by means of pathologic examination after surgical resection in all patients. MR images obtained with all sequences and triple-phase helical CT images were reviewed independently by three radiologists on a segment-by-segment basis. Accuracy for diagnosis of HCC was assessed by applying receiver operating characteristic (ROC) analysis to observations of 78 hepatic segments with at least one HCC nodule and 70 segments without HCC. RESULTS: The diagnostic accuracy of findings at ferumoxides-enhanced MR imaging (with mean area-under-the-ROC-curve [A(z)] values for the three observers of 0.986, 0.979, and 0.980) was significantly higher (P <.001) than that of findings at triple-phase helical CT (with mean A(z) values for the three observers of 0.945, 0.948, and 0.964). The mean sensitivity of MR imaging (95%, 222 of 234 segments) was also significantly higher than that of triple-phase helical CT (88%, 205 of 234 segments) (P =.001, McNemar test). The mean specificity was 97% (261 of 270 segments) for MR imaging and 98% (264 of 270 segments) for CT, but this difference was not significant (P =.754, McNemar test). CONCLUSION: Ferumoxides-enhanced MR imaging is superior to triple-phase helical CT for the preoperative depiction of HCC.

Adult↗
PubMed2003

Correlation between the echogenicity of dysplastic nodules and their histopathologically determined fat content.

OBJECTIVE: To correlate the echogenicity of dysplastic nodules in cirrhotic liver with the difference in fat content between lesions and surrounding liver. METHODS: This retrospective study involved 65 histopathologically proved dysplastic nodules (39 high grade and 26 low grade). Their echogenicity compared with that of surrounding parenchyma was determined sonographically, and differences in the proportions of fat globules contained in the nodules and in surrounding liver tissue were evaluated histopathologically. The sonographic and histopathologic findings were correlated. RESULTS: Among the 65 dysplastic nodules, echogenicity was high in 30 (46%), equal in 5 (8%), and low in 30 (46%). In all cases, there was significant correlation between echogenicity on sonographic imaging and the difference in fat content between nodules and surrounding liver tissue (P < .01). There was, however, no significant correlation between the degree of dysplasia and sonographic echogenicity (P > .05). CONCLUSIONS: The echogenicity of dysplastic nodules correlated with their fat content. Echogenicity did not, however, predict whether the grade of a nodule was high or low.

Adult↗
PubMed2002

Detection of hepatocellular carcinoma: value of adding delayed phase imaging to dual-phase helical CT.

OBJECTIVE: The purpose of our study was to determine the value of adding delayed phase imaging to dual-phase helical CT for the detection of hepatocellular carcinoma. SUBJECTS AND METHODS: One hundred thirteen patients with 131 hepatocellular carcinomas underwent triple-phase helical CT. The diagnosis was established by pathologic examination after surgical resection in all patients. For triple-phase helical CT, hepatic arterial, portal venous, and delayed phase scanning began 30, 60, and 180 sec, respectively, after the injection of 120 mL of iodinated contrast material. Dual-phase helical CT excluding delayed phase and triple-phase helical CT images were reviewed independently by three radiologists on a segment-by-segment basis. Diagnostic accuracy was assessed using receiver operating characteristic analysis in 330 resected segments. Sensitivities and specificities were calculated. The value of the delayed phase images in the characterization of hepatocellular carcinoma was also assessed. RESULTS: The diagnostic accuracy of triple-phase helical CT including delayed phase (area under the curve [A(z)], 0.973) was significantly higher than that of dual-phase helical CT (A(z), 0.954). The mean sensitivity of triple-phase CT (89%) was also significantly higher than that of dual-phase CT (86%). The mean specificities of triple-phase CT (99%) and dual-phase CT (99%) were equal. Delayed phase images were helpful in the characterization of hepatocellular carcinoma in 14% of patients. CONCLUSION: The addition of delayed phase imaging to dual-phase helical CT is valuable for the detection and characterization of hepatocellular carcinoma.

Adult↗
PubMed2002

CT detection of hepatocellular carcinoma in advanced liver cirrhosis: correlation of helical CT and explanted liver.

OBJECTIVE: The objective of this study was evaluate the diagnostic efficacy of three-phase helical dynamic CT in the detection of hepatocellular carcinomas in patients with advanced liver cirrhosis. MATERIALS AND METHODS: Three-phase helical dynamic CT in 77 patients with advanced liver cirrhosis was evaluated prospectively before orthotopic liver transplantation. The histopathologically confirmed hepatocellular carcinomas in the explanted livers were compared with pretransplantation CT results by one-to-one correlation. RESULTS: Histopathologic examination of the explanted livers revealed 72 hepatocellular carcinomas in 41 patients. The size of the hepatocellular carcinomas was 0.5-14.0 cm (mean, 1.6 cm). The use of helical dynamic CT enabled the detection of 38 of 72 hepatocellular carcinomas (sensitivity, 53%). Fifteen of 35 (43%) hepatocellular carcinomas smaller than 2 cm and 23 of 37 (62%), hepatocellular carcinomas ranging from 2.0 cm to 14.0 cm were detected. Patient sensitivity and specificity in the detection of hepatocellular carcinoma were 81% (33/41) and 94% (34/36), respectively. CONCLUSIONS: Three-phase helical dynamic CT is insensitive for detection of hepatocellular carcinomas in patients with advanced liver cirrhosis, especially for hepatocellular carcinomas smaller than 2 cm.

Adolescent↗
PubMedDate not supplied

Indeterminate small, low-attenuating hepatocellular nodules on helical CT in patients with chronic liver disease: 2-year follow-up.

To evaluate the clinical significance of indeterminate, small, low-attenuating nodular lesions on helical dynamic computed tomography (CT) in chronic liver diseases, CT images were reviewed retrospectively in 281 patients. Indeterminate, low-attenuating nodular lesions less than 20 mm in diameter were followed for 24 to 35 months. Of 127 nodules in 73 patients, 21 nodules turned out to be hepatocellular carcinomas (16%), 25 nodules (20%) became larger, while the remaining 81 nodules (64%) remained unchanged or disappeared. Some low-attenuating nodules larger than 10 mm in diameter may develop into hepatocellular carcinoma.

Adult↗
PubMedDate not supplied

Small hepatocellular carcinoma: ultrasonographic findings and histopathologic correlation.

It is known that small hepatocellular carcinoma (HCCs) were usually hypoechoic at ultrasonography (US). In this study, we analyzed US findings of 42 small HCCs less than 2 cm in diameter and correlated them with histopathologic findings. US parameters were tumor size, tumor echogenecity, and morphologic features (peripheral halo, lateral shadow, posterior enhancement, and mosaic pattern), while histopathologic parameters were Edmonson grade and microscopic features (coagulation necrosis, interstitial fibrosis, fatty metamorphosis, sinusoidal dilatation, hemorrhage, encapsulation, and internal septation). One-third of HCCs was not hypoechoic. Tumor echogenecity and morphologic features were variable, regardless of tumor differentiation and microscopic features. In our study, it seemed that US detected histopathologic changes in small HCCs more frequently than previously known, but none of these US findings could suggest a specific histopathologic finding in small HCCs less than 2 cm in diameter.

Biopsy, Fine-Needle↗
PubMedDate not supplied

Major complications after radio-frequency thermal ablation of hepatic tumors: spectrum of imaging findings.

Although radio-frequency (RF) ablation has been accepted as a promising and safe technique for treatment of unresectable hepatic tumors, investigation of its complications has been limited. According to the multicenter (1,139 patients in 11 institutions) survey data of the Korean Study Group of Radiofrequency Ablation, a spectrum of complications occurred after RF ablation of hepatic tumors. The prevalence of major complications was 2.43%. The most common complications were hepatic abscess (0.66%), peritoneal hemorrhage (0.46%), biloma (0.20%), ground pad burn (0.20%), pneumothorax (0.20%), and vasovagal reflex (0.13%). Other complications were biliary stricture, diaphragmatic injury, gastric ulcer, hemothorax, hepatic failure, hepatic infarction, renal infarction, sepsis, and transient ischemic attack. One procedure-related death (0.09%) occurred (due to peritoneal hemorrhage). Three important strategies for decreasing the rate of complications are prevention, early detection, and proper management. A physician who performs RF ablation of hepatic malignancies should be aware of the broad spectrum of major complications so that these strategies can be used.

Aged↗
PubMedDate not supplied

Hepatocellular carcinoma treated with radio-frequency ablation: spectrum of imaging findings.

Contrast material-enhanced Doppler or gray-scale harmonic ultrasonography (US) may help determine the completeness or long-term therapeutic efficacy of radio-frequency (RF) ablation of hepatocellular carcinoma (HCC). Successfully treated HCC is devoid of vascularity at color or power Doppler US. When the tumor is not completely treated, residual viable tumor can be detected. These contrast-enhanced US techniques may also help identify residual tumor when performed during repeat RF ablation, when accurate localization of viable tumor is needed. To date, contrast-enhanced computed tomography (CT) has been the most widely used imaging modality in the evaluation of therapeutic response after RF ablation of HCC. At follow-up CT, successfully ablated lesions appear as low-attenuation areas with no foci of contrast enhancement either within or at the periphery of the treated lesion, whereas any foci of enhancement indicate residual or recurrent tumor. Reactive hyperemia in tissue surrounding the ablated lesion, iatrogenic arterioportal shunting, and small intralesional air pockets are frequently seen at immediate follow-up CT. Gadolinium-enhanced dynamic magnetic resonance imaging is also useful in assessing therapeutic response following RF ablation of HCC, particularly when CT findings are inconclusive. Familiarity with these imaging findings is helpful in this setting.

Adult↗