Seung Hoon Kim

Seonam University, Onyang, South Chungcheong, South Korea

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Publications (52)112.42 Total impact

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    ABSTRACT: To diagnose rectal cancer and monitor treatment response after preoperative concurrent chemoradiotherapy (CCRT) in rectal cancer patients using proton-1 magnetic resonance spectroscopy ((1)H-MRS). We enrolled 134 rectal cancer patients before treatment, of whom 34 underwent preoperative CCRT and follow-up MR spectroscopy before surgery. (1)H-MRS was performed using a six-channel phased-array coil at 3.0 T. We evaluated the presence of a choline peak at 3.2 ppm, and lipid peaks at 0.9 and 1.3 ppm, and glutamine and glutamate peaks at 2.1-2.3 and 2.7 ppm seen at two TEs (40 and 135 ms). We divided MR spectra patterns into two groups (A and B). A choline peak at 3.2 ppm seen in both TEs was characteristic for rectal cancer before treatment. Of 103 patients, 55 (53%) showed an elevated choline peak before treatment (type A). Type A spectra were seen in 68% of patients (23/34) before preoperative CCRT. After CCRT, the choline peak disappeared, resulting in only the lipid peak at 1.3 ppm (type B) in 97% of patients (33/34). We optimized a localized in vivo(1)H-MRS method for detection of rectal adenocarcinoma and monitoring treatment response after preoperative CCRT. The method appears to be a promising and feasible noninvasive modality.
    Magnetic Resonance Imaging 04/2012; 30(6):848-53. · 2.06 Impact Factor
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    ABSTRACT: This study was designed to compare the diagnostic performance of gadoxetic acid-enhanced magnetic resonance imaging (MRI) with gadobenate dimeglumine-enhanced MRI for preoperatively detecting hepatocellular carcinoma (HCC). Eighteen consecutive patients (17 men and one woman, age range: 31-73 years) with 22 HCCs underwent examinations with gadoxetic acid enhanced MRI and gadobenate dimeglumine-enhanced MRI on a 3.0-Tesla unit. The diagnosis of HCC was established after surgical resection and pathological conformation. Three observers independently reviewed each MR image in a random order on a tumor-by-tumor basis. The diagnostic accuracy of these techniques for the detection of HCC was assessed by performing an alternative free-response receiver operating characteristic (ROC) analysis. The sensitivity and positive predictive values were evaluated. The average value of the area under the ROC curve (Az) for gadoxetic acid enhanced MRI (0.887) was not significantly different from the Az (0.899) for gadobenate dimeglumine-enhanced MRI (p > 0.05). The overall sensitivities of gadoxetic acid enhanced MRI and gadobenate dimeglumine-enhanced MRI were 80% and 83%, respectively, with no significant difference (p > 0.05). The differences of the positive predictive values for the two contrast agents for each observer were not statistically significant (p > 0.05). The diagnostic performance of gadoxetic acid-enhanced MRI and gadobenate dimeglumine-enhanced MRI for preoperatively detecting HCC is quite similar.
    Korean journal of radiology: official journal of the Korean Radiological Society 01/2010; 11(4):433-40. · 1.32 Impact Factor
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    ABSTRACT: We compared the diagnostic performance of gadoxetic acid-enhanced MRI with that of triple-phase 16-, 40-, and 64-MDCT in the preoperative detection of hepatocellular carcinoma (HCC). Sixty-two consecutively registered patients (54 men, eight women; age range, 31-67 years) with 83 HCCs underwent triple-phase (arterial, portal venous, equilibrium) CT at 16-, 40-, or 64-MDCT and gadoxetic acid-enhanced 3-T MRI. The diagnosis of HCC was established after surgical resection. Three observers independently and randomly reviewed the MR and CT images on a tumor-by-tumor basis. The diagnostic accuracy of these techniques in the detection of HCC was assessed with alternative free response receiver operating characteristic (ROC) analysis. Sensitivity, positive and negative predictive values, and sensitivity according to tumor size were evaluated. For each observer, the areas under the ROC curve were 0.971, 0.959, and 0.967 for MRI and 0.947, 0.950, and 0.943 for CT. The differences were not statistically significant between the two techniques for each observer (p > 0.05). The differences in sensitivity and positive and negative predictive values between the two techniques for each observer were not statistically significant (p > 0.05). Among 10 HCCs 1 cm in diameter or smaller, each of the observers detected seven tumors with MRI. With CT, one observer detected five, one observer detected four, and one observer detected three HCCs with no statistically significant difference (p > 0.05). Gadoxetic acid-enhanced MRI and triple-phase MDCT have similar diagnostic performance in the preoperative detection of HCC, but MRI may be better than MDCT in the detection of HCC 1 cm in diameter or smaller.
    American Journal of Roentgenology 07/2009; 192(6):1675-81. · 2.90 Impact Factor
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    ABSTRACT: PurposeThe aim of this study was to describe pancreatic involvement in von Hippel-Lindau (VHL) disease and to document the changes that occur in pancreatic lesions. MethodsWe retrospectively analyzed the medical records and CT scans of 18 VHL patients who were diagnosed between 1994 and 2007 at the Samsung Medical Center. The clinical history with a detailed family history, biochemical test results, and imaging studies of the pancreas, adrenal glands, and kidneys were reviewed. Genetic analysis was performed in 12 patients. The changes in pancreatic lesions, such as an increase in cystic lesions, calcifications, and dilatation of the pancreatic duct, were analyzed in patients who had CT scans at least 1year apart. ResultsPancreatic lesions existed in 89% (16/18) of the patients. All 16 patients had multiple cystic lesions. Two patients had co-existing neuroendocrine tumors (NET), and two patients had co-existing serous cystadenomas (SCA). At least one of three features of pancreatic lesions (cystic lesions, calcifications, and dilatation of the pancreatic duct) progressed in all nine patients who had CT scans 1year apart. ConclusionPancreatic involvement in VHL disease was relatively common in Korean patients. The most common type of pancreatic involvement was a multiple cystic lesion. NET and SCA existed in approximately 10% of VHL patients with pancreatic involvement. Pancreatic lesions in VHL disease progressed, at least according to radiological images.
    Journal of Gastroenterology 01/2009; 44(5):447-452. · 3.79 Impact Factor
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    ABSTRACT: To compare the in vivo gastric injury observed during radiofrequency (RF) ablation of the liver abutting the stomach before and after the intragastric administration of chilled saline. Twenty RF ablation zones were created in the livers of 10 pigs with a 1-cm-exposed active tip of an internally cooled electrode under ultrasound guidance for 10 min. Ten RF ablation zones were created before (non-saline group) and after (saline group) the intragastric administration of approximately 1000 mL of chilled saline, and 20 RF ablation zones were made in the posterior part of the left lobe abutting the stomach. The frequency and severity of the thermal injury observed in the stomach of the two groups were compared histologically. All the resected gastric specimens showed thermal injuries of varying degrees of severity. The largest diameter of the gastric injury was significantly smaller in the saline group (mean 1.5 cm; range 1.3-1.8 cm) than in the non-saline group (mean 2.1cm; range 1.8-2.4 cm) (p=0.000). The saline group showed significantly less thermal injury to the muscular layer of the gastric wall by the histopathology (p=0.033). The intragastric administration of chilled saline might be a useful technique for reducing the severity of gastric injury during RF ablation of the liver abutting the stomach.
    European journal of radiology 09/2008; 72(1):154-9. · 2.65 Impact Factor
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    ABSTRACT: The CT accreditation program was established in 2004 by the Korean Institute for Accreditation of Medical Image (KIAMI) to confirm that there was proper quality assurance of computed tomography (CT) images. We reviewed all the failed CT phantom image evaluations performed in 2005 and 2006. We analyzed 604 failed CT phantom image evaluations according to the type of evaluation, the size of the medical institution, the parameters of the phantom image testing and the manufacturing date of the CT scanners. The failure rates were 10.5% and 21.6% in 2005 and 2006, respectively. Spatial resolution was the most frequently failed parameter for the CT phantom image evaluations in both years (50.5% and 49%, respectively). The proportion of cases with artifacts increased in 2006 (from 4.5% to 37.8%). The failed cases in terms of image uniformity and the CT number of water decreased in 2006. The failure rate in general hospitals was lower than at other sites. In 2006, the proportion of CT scanners manufactured before 1995 decreased (from 12.9% to 9.3%). The continued progress in the CT accreditation program may achieve improved image quality and thereby improve the national health of Korea.
    Korean Journal of Radiology 01/2008; 9(4):354-63. · 1.56 Impact Factor
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    ABSTRACT: Percutaneous interventional procedures under image guidance, such as biopsy, ethanol injection therapy, and radiofrequency ablation play important roles in the management of hepatocellular carcinomas. Although uncommon, the procedures may result in tumor implantation along the needle tract, which is a major delayed complication. Implanted tumors usually appear as one or a few, round or oval-shaped, enhancing nodules along the needle tract on CT, from the intraperitoneum through the intercostal or abdominal muscles to the subcutaneous or cutaneous tissues. Radiologists should understand the mechanisms and risk factors of needle tract implantation, minimize this complication, and also pay attention to the presence of implanted tumors along the needle tract during follow-up.
    Korean Journal of Radiology 01/2008; 9(3):268-74. · 1.56 Impact Factor
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    ABSTRACT: To compare diagnostic performance of ferucarbotran-enhanced 3.0-T magnetic resonance (MR) imaging using parallel imaging technique with that of triple-phase multidetector row computed tomography (MDCT) for the preoperative detection of hepatocellular carcinoma (HCC). Eighty-six consecutive patients with a total of 128 surgically proven HCCs were enrolled in this study. All patients underwent ferucarbotran-enhanced 3.0-T MR imaging using parallel imaging technique and triple-phase MDCT before hepatic resection. Three experienced radiologists independently analyzed each images on a segment-by-segment basis. The accuracy of these techniques for the detection of HCC was assessed by performing a receiver operating characteristic (ROC) analysis of 104 resected hepatic segments with at least 1 HCC and 113 resected hepatic segments without HCC. The mean value of the area under the ROC curve (Az) of the ferucarbotran-enhanced 3.0-T MR imaging (0.990) was significantly higher than that of the triple-phase MDCT (0.964) (P = 0.00). The mean sensitivity of the ferucarbotran-enhanced 3.0-T MR imaging (98.1%) was significantly higher than that of the triple-phase MDCT (92.9%) (P = 0.00). The higher sensitivity was largely attributable to a greater ability of the 3.0-T MR imaging to detect small HCC (< or =1 cm) (92.6% in 3.0-T MR imaging and 37.0% in MDCT; P = 0.00). No significant difference was found for their mean specificities (98.2% in 3.0-T MR imaging and 97.6% in MDCT; P = 0.86). Ferucarbotran-enhanced 3.0-T MR imaging using parallel imaging technique is a more accurate diagnostic tool than triple-phase MDCT for the preoperative detection of HCC. Ferucarbotran-enhanced 3.0-T MR imaging has a higher sensitivity than triple-phase MDCT, especially for small HCCs (< or =1 cm).
    Journal of Computer Assisted Tomography 01/2008; 32(3):379-85. · 1.58 Impact Factor
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    ABSTRACT: To compare prospectively between 3-T magnetic resonance imaging (MRI) and multidetector row computed tomography (MDCT) for the local staging of rectal cancer. During a recent 8-month period, both 3-T MRI with a phased array coil and MDCT scanner were used to preoperatively examine 31 consecutive patients. Preoperatively, the 3 experienced reviewers independently assessed the MRI and MDCT findings for the depth of tumor invasion into the rectal wall (T). Regional lymph node metastasis (N) was assessed by the 3 reviewers working in consensus. For T staging, we used a modified T staging (<or=T2, T3, and T4 staging). The results of the MRI and MDCT findings were compared based on the diagnosis of the resected specimens. At histopathology, T1 was identified in 8 patients, T2 in 6, and T3 in 17 patients. The sensitivity, specificity, and accuracy for T2 staging or less between MRI and MDCT were 93% and 79%, 88% and 76%, and 91% and 77%, respectively. The sensitivity, specificity, and accuracy for T3 between MRI and MDCT were 92% and 73%, 93% and 83%, and 92% and 78%, respectively; there was a statistically significant difference for the T2 and T3 staging or less (P < 0.01). For N staging, MRI and CT can predict accurately in 88% and 77%, respectively (P > 0.05). For local staging of rectal cancer, 3-T MRI is more accurate than MDCT for determining the depth of tumor invasion and the extent of lymph node metastasis.
    Journal of Computer Assisted Tomography 10/2007; 31(6):853-9. · 1.58 Impact Factor
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    ABSTRACT: To elucidate the attributes of hepatic infarction after radiofrequency ablation (RFA) of hepatocellular carcinoma (HCC) with an internally cooled electrode. The authors retrospectively reviewed follow-up computed tomographic (CT) scans (follow-up period, 1-60.1 months; mean, 15.4 months) in 872 consecutive patients (male:female ratio, 672:200; mean age, 59.5 years) who had undergone 1,120 sessions of RFA for 1,335 HCCs with an internally cooled electrode. Diagnosis of hepatic infarction was made on the basis of CT findings. The authors evaluated the frequency of hepatic infarction, clinical features, initial and follow-up CT findings, accompanied complications, and prognosis. Potential risk factors were evaluated with multiple logistic regression analysis. The frequency of hepatic infarction was 1.8% (20 of 1,120 sessions). Common presenting symptoms were abdominal pain (16 of 20 patients) and fever (11 of 20 patients). All infarctions were found at the first follow-up CT examination. Gas collections were noted in 65% of patients. All lesions showed progressive shrinkage. Accompanied complications were biloma (n = 2), abscess (n = 2), and portal vein thrombosis (n = 1). One patient with a lobar infarction died from hepatic failure. Older age (P = .048) and larger tumor size (P = .026) were statistically significant risk factors by multivariate analysis. RFA complicated by hepatic infarction is uncommon. Although hepatic infarction can be managed conservatively in most cases, possible extensive involvement should be considered seriously because it may cause mortality.
    Journal of Vascular and Interventional Radiology 10/2007; 18(9):1126-33. · 2.00 Impact Factor
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    ABSTRACT: The aim of this study was to compare phased-array 3-T MRI and endorectal sonography in the preoperative staging of rectal cancer. During an 8-month period, 24 patients with rectal cancer underwent both 3-T MRI performed with phased-array coils and 7.5- to 10-MHz endorectal sonography in the 3 weeks before surgical resection. Three radiologists independently reviewed the MR and endorectal sonographic images. The histopathologic findings in resected specimens were used to evaluate the sensitivities and specificities of these techniques for invasion of the muscularis propria and perirectal tissue and for lymph node involvement. Receiver operating characteristic (ROC) analysis was used to compare the diagnostic accuracies of the techniques. For muscularis propria invasion, the mean sensitivities of both MRI and endorectal sonography were 100%, and the mean specificities were 66.7% and 61.1%, respectively. The differences in the mean sensitivities and specificities were not statistically significant (p > 0.05 in each case). For perirectal tissue invasion, MRI and endorectal sonography had comparable sensitivities and specificities (91.1% vs 100%, 92.6% vs 81.5%; p > 0.05 in each case). They also had similar sensitivities and specificities for lymph node involvement (63.6% vs 57.6%, 92.3% vs 82.1%; p > 0.05 in each case). ROC curves for muscularis propria invasion and lymph node involvement showed no differences in diagnostic accuracy. The mean area under the ROC curve for endorectal sonography (A(Z) = 0.996) for perirectal tissue invasion, however, showed higher accuracy than that of MRI (A(Z) = 0.938, p = 0.028). The sensitivity, specificity, and accuracy of 3-T MRI were similar to those of endorectal sonography for muscularis propria invasion and lymph node involvement, but for perirectal tissue invasion, 3-T MRI was less accurate than endorectal sonography.
    American Journal of Roentgenology 12/2006; 187(6):1557-62. · 2.90 Impact Factor
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    ABSTRACT: PURPOSE For the compensation of decreased medical fee, the rate of self referral has been increased. If untrained physicians operate radiologic equipments or try to interpret images, the possibility of poor quality examination will be increased. Accreditation system of CT, MRI and mammography in Korea started December 2004. To operating MRI, radiologist in the facility is mandatory; however, large portion of CT and mammography equipment has been operated in the nonradiologist's private office. The purpose of this study was to evaluate present distribution of CT and mammography unit in Korea and to compare failure rate of private office by radiologist's with that of nonradiologist's. METHOD AND MATERIALS Since December 2004, 1630 mammography, 1547 CT underwent quality inspection. Among them, 927 mammography units and 629 CT units were operated in the private offices. We defined a facility as radiologist office if full-time radiologist works in that clinic. 54 mammography units and 17 CT units were excluded because information about personnel is not available. RESULTS Among 873 mammography units, 327 (37%) were operated at radiologist’s office and 546 (63%) at the nonradiologist’s. The failure rate of mammography was 2.5% (8/327) in radiologist’s office and 6.8% (37/547) in nonradiologist’s office. Among 612 CT units, 230 (38%) were operated at radiologist’s office and 382 (62%) at the nonradiologist’s. The failure rate of CT was 7.4% (17/230) in radiologist’s office and 16.0% (61/382) in nonradiologist’s office. CONCLUSION The number of imaging facilities in nonradiologist’s office was much more than that of radiologist’s office. However, the failure rates of nonradiologist’s were much higher than that of radiologist’s. This result implicates the importance of radiologist’s role for quality control. Awareness of the radiologist’s specialty of quality management in medical imaging is also important. CLINICAL RELEVANCE/APPLICATION Radiologists are specialist for medical imaging and have an important role for quality control.
    Radiological Society of North America 2006 Scientific Assembly and Annual Meeting; 11/2006
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    ABSTRACT: To verify changes in the signal-to-noise ratios (SNRs) and contrast-to-noise ratios (CNRs) of hypervascular hepatocellular carcinomas (HCCs) on ferucarbotran-enhanced dynamic T1-weighted MR imaging. Fifty-two patients with 61 hypervascular HCCs underwent ferucarbotran-enhanced dynamic MR imaging, and then hepatic resection. Hypervascular HCCs were identified when definite enhancement was noted during the arterial dominant phase of three-phase MDCT. Dynamic MR Images with T1-weighted fast multiplanar spoiled gradient-recalled echo sequence (TR200/TE4.2) were obtained before and 20 s, and 1, 3, 5, and 10 min, after bolus injection of ferucarbotran. We estimated the signal intensities of tumors and livers, and calculated the SNRs and CNRs of the tumors. On ferucarbotran-enhanced dynamic MR imaging, SNR measurements showed a fluctuating pattern, namely, an increase in SNR followed by a decrease and a subsequent increase (or a decrease in SNR followed by a increase and a subsequent decrease) in 50 (82.0%) of 61 tumors, a single-peak SNR pattern (highest SNR on 20 s, 1, 3, or 5 min delayed images followed by a decrease) in seven (11.5%), and a decrease in SNR followed by an increase in four (6.6%). Maximum absolute CNRs with positive value were noted on 10 min delayed images in 41 (67.2%) tumors, and maximum absolute CNRs with negative value were observed on 20 s delayed images in 12 (19.7%) and on 1 min delayed images in eight (13.1%). Despite showing various SNR and CNR changes, the majority of hypervascular HCCs demonstrated a fluctuating SNR pattern on ferucarbotran-enhanced dynamic MR imaging and a highest CNR on 10 min delayed image, which differed from the classic enhancement pattern on multiphasic CT.
    European Journal of Radiology 10/2006; 59(3):424-31. · 2.51 Impact Factor
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    ABSTRACT: To compare the diagnostic performance of a variety of magnetic resonance imaging (MRI) sequences, in order to identify the most effective ferucarbotran-enhanced sequence for the detection of multiple small hepatic VX2 carcinomas in rabbits. Fifteen rabbits with experimentally induced 135 VX2 carcinomas in the liver underwent ferucarbotran-enhanced MRI using the following nine pulse sequences: a fat-suppressed fast spin-echo (FSE) sequence with two echo times (TE) (proton density- and T2-weighted images), four different T2*-weighted fast multiplanar GRASS (gradient-recalled acquisition in the steady state) (FMPGR) with the combination of three TEs (9, 12, 15 ms, respectively) and two flip angles (20 degrees , 80 degrees, respectively), T2*-weighted fast multiplanar spoiled GRASS (FMPSPGR), T1-weighted FMPSPGR, and dynamic T1-weighted FMPSPGR. All images were reviewed by three radiologists with quantitative and qualitative analysis. Tumor-to-liver contrast-to-noise ratio of the proton density-weighted FSE sequence was significantly higher than those of the others (p<0.05). The lesion conspicuities of proton density- and T2-weighted FSE and T2*-weighted FMPGR (TE/flip angle, 9/20 degrees and 12/20 degrees ) images were better and the image artifacts of T2*-weighted FMPGR (TE/flip angle, 15/20 degrees and 12/80 degrees ) and T2*-weighted FMPSPGR images were more prominent than those of the others (p<0.05). The lesion detection in T2- and proton density-weighted FSE and T2*-weighted FMPGR (TE/flip angle, 12/20 degrees ) images were superior to those of the others and for the detection of very small hepatic tumors of less than 5 mm, the sensitivities of these sequences were less than 30%. Ferucarbotran-enhanced T2- and proton density-weighted FSE and T2*-weighed FMPGR (TE/flip angle, 12/20 degrees ) images were found to be the most effective pulse sequences for the detection of multiple small hepatic VX2 carcinomas but these sequences were limited in the detection of very small hepatic tumors of less than 5 mm in size.
    European Journal of Radiology 09/2006; 59(3):413-23. · 2.51 Impact Factor
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    ABSTRACT: 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.
    European Radiology 06/2006; 16(5):972-80. · 4.34 Impact Factor
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    ABSTRACT: The purpose of our study was to assess the therapeutic results of radiofrequency ablation of hepatocellular carcinoma (HCC) based on the histologic grades of the tumors. Between April 1999 and December 2003, 95 patients with nodular HCC were treated with percutaneous radiofrequency ablation. All tumors were histologically proven by sonography-guided percutaneous biopsy and were classified as Edmondson-Steiner grade I HCC (n = 38) (mean, 2.3 cm) (group 1), grade II HCC (n = 50) (mean, 2.4 cm) (group 2), or grade III HCC (n = 7) (mean, 2.8 cm) (group 3). All patients underwent contrast-enhanced three-phase helical CT examination before and after radiofrequency ablation. After retrospective review of the medical records and follow-up CT examinations, the rates of technique effectiveness, local tumor progression, cumulative survival, and cancer-free survival using a Kaplan-Meier method were calculated and compared among the groups. Technique effectiveness rates in groups 1, 2, and 3 were 87% (27/31), 71% (30/42), and 43% (3/7), respectively, with statistical significance (p = 0.032). Local tumor progression rates in groups 1, 2, and 3 were 16% (5/31), 36% (15/42), and 71% (5/7), respectively, with statistical significance (p = 0.013). Five-year cumulative survival rates in groups 1, 2, and 3 were 71%, 44%, and 43%, respectively, with no statistical significance (p > 0.05). Four-year cancer-free survival rates in groups 1, 2, and 3 were 39%, 10%, and 0%, respectively (p < 0.05 for groups 1 vs 2; p > 0.05 for groups 1 vs 3 and groups 2 vs 3). The histologic grade of HCC is an important factor influencing therapeutic results with survival after radiofrequency ablation.
    American Journal of Roentgenology 05/2006; 186(5 Suppl):S327-33. · 2.90 Impact Factor
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    ABSTRACT: To evaluate the long-term follow-up results of percutaneous ethanol injection (PEI) for the treatment of hepatocellular carcinoma (HCC) in Korea. Sixty-eight nodular HCCs initially detected in 64 patients, were subjected to US-guided PEI as a first-line treatment. Long-term survival rates, local tumor progression rates, and complications were evaluated, as were the influences of tumor size and Child-Pugh class on these variables. No major complications occurred. The overall survival rates of the 64 patients at three and five years were 71% and 39%, and their cancer-free survival rates were 22% and 15%, respectively. The overall survival rate of patients with a small HCC (< or =2 cm) was significantly higher (p = 0.014) than that of patients with a medium-sized HCC (< or =2 cm). The overall survival rate of patients with Child-Pugh class A was significantly higher (p = 0.049) than that of patients with Child-Pugh class B. Of 59 cases with no residual tumor, local tumor progression was observed in ablation zones in 18, and this was not found to be significantly influenced by tumor size or Child-Pugh class. The results of our investigation of the long-term survival rates of PEI in HCC patients in Korea (a hepatitis B virus-endemic area) were consistent with those reported previously in hepatitis C endemic areas. Patients with a smaller tumor or a better liver function exhibited superior survival rates.
    Korean Journal of Radiology 01/2006; 7(3):187-92. · 1.56 Impact Factor
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    ABSTRACT: PURPOSE To compare 3T high-field MR imaging and endoluminal ultrasonography (EUS) for preoperative local staging of rectal cancer. METHOD AND MATERIALS During a recent 6 months, 17 patients with rectal cancer underwent both 3T MR imaging using phased-array coil and 7.5-10-MHz EUS within 3 weeks before surgical resection. Three radiologists independently reviewed the MR and EUS images. On the basis of the histology of resected specimens, we evaluated sensitivities and specificities of these techniques for invasion of muscularis propria, perirectal tissue, and for lymph node involvement. We also assessed the accuracies for perirectal tissue invasion by conducting a receiver operating characteristic (ROC) analysis. RESULTS For muscularis propria invasion, the mean sensitivities of MR imaging and EUS were both 100.0%, while their mean specificities were 80.0% and 60.0%, respectively. The differences in the mean sensitivities and specificities were not statistically significant (P > .05 in each case). For perirectal tissue invasion, MR imaging and EUS had comparable sensitivities and specificities (86.7% vs 100.0%, 90.5% vs 85.7%, P > .05 in each case). MR imaging and EUS also had similar sensitivities and specificities for lymph node involvement (62.5% vs 37.5%, 63.0% vs 77.8%, P > .05 in each case). However, ROC curve of EUS (mean Az value = 1.000) for perirectal tissue invasion showed better diagnostic accuracy than that of MR imaging (mean Az value = 0.913, P = .031). CONCLUSION Compared with 3T MR imaging, EUS was more accurate for perirectal tissue invasion and can be helpful in selecting patients for available therapeutic strategies.
    Radiological Society of North America 2005 Scientific Assembly and Annual Meeting; 11/2005
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    ABSTRACT: PURPOSE To quantify the CT findings of neuroendocrine tumors arising from the stomach and identify their characteristic features. METHOD AND MATERIALS For the past 7 years, 31 patients among the 41 (M:F=28:13; age range, 33-79 years; mean, 58.5 years) with pathologically proven neuroendocrine tumors underwent CT prior to surgery. Only in 22 patients (M:F=17:5; age range, 33-79 years; mean age, 58.7 years), however, their tumors could be discriminated on CT images, which were retrospectively reviewed by two radiologists in consensus, regarding the lesion location, size, thickness, attenuation value on postcontrast scan, degree of enhancement on visual estimation, ulceration, layering in the peripheral portion of the lesion, Borrmann type, perigastric fat stranding, regional lymphadenopathy, distant metastasis, and presence of coexisting malignancy. No postcontrast scan was available in 2 patients. RESULTS There were 3 carcinoid tumors, 4 composite glandular-endocrine carcinomas, 4 endocrine carcinomas, 7 neuroendocrine carcinomas, and 4 small cell carcinomas. The lesion centers were located mainly at the lower body (22.7%, 5/22) and antrum (36.4%, 8/22). The lesion size was 64.2±32.8 mm (range, 13-140 mm), the thickness was 21.1±10.8 mm (range, 9-47 mm), and the attenuation value on postcontrast scan was 79.6±23.4 HU (43-107 mm). Only the lesion size between composite glandular-endocrine carcinoma (56.8±11.5 mm) and endocrine carcinoma (97.0±31.8 mm) had statistically significant difference (p=0.021, Mann-Whitney U test). There were moderate enhancement on visual estimation in 60% (12/20), ulceration in 68.2% (15/22), and peripheral layering in 31.8% (7/22). Borrmann type III was the most common (68.2%, 15/22). Perigastric fat stranding was observed in 72.7% (16/22), and regional lymphadenopathy in 72.7% (16/22). Two patients had metastasis to the liver and 1 patient to the bilateral adrenal glands. Three patients had coexisting malignancy. CONCLUSION Neuroendocrine tumors are rare in the stomach. On macroscopic presentation, they are usually seen as a large tumor of Borrmann type III with moderate enhancement. Perigastric fat stranding and regional lymphadenopathy are seen frequently. DISCLOSURE PURPOSE To quantify the CT findings of neuroendocrine tumors arising from the stomach and identify their characteristic features. METHOD AND MATERIALS For the past 7 years, 31 patients among the 41 (M:F=28:13; age range, 33-79 years; mean, 58.5 years) with pathologically proven neuroendocrine tumors underwent CT prior to surgery. Only in 22 patients (M:F=17:5; age range, 33-79 years; mean age, 58.7 years), however, their tumors could be discriminated on CT images, which were retrospectively reviewed by two radiologists in consensus, regarding the lesion location, size, thickness, attenuation value on postcontrast scan, degree of enhancement on visual estimation, ulceration, layering in the peripheral portion of the lesion, Borrmann type, perigastric fat stranding, regional lymphadenopathy, distant metastasis, and presence of coexisting malignancy. No postcontrast scan was available in 2 patients. RESULTS There were 3 carcinoid tumors, 4 composite glandular-endocrine carcinomas, 4 endocrine carcinomas, 7 neuroendocrine carcinomas, and 4 small cell carcinomas. The lesion centers were located mainly at the lower body (22.7%, 5/22) and antrum (36.4%, 8/22). The lesion size was 64.2±32.8 mm (range, 13-140 mm), the thickness was 21.1±10.8 mm (range, 9-47 mm), and the attenuation value on postcontrast scan was 79.6±23.4 HU (43-107 mm). Only the lesion size between composite glandular-endocrine carcinoma (56.8±11.5 mm) and endocrine carcinoma (97.0±31.8 mm) had statistically significant difference (p=0.021, Mann-Whitney U test). There were moderate enhancement on visual estimation in 60% (12/20), ulceration in 68.2% (15/22), and peripheral layering in 31.8% (7/22). Borrmann type III was the most common (68.2%, 15/22). Perigastric fat stranding was observed in 72.7% (16/22), and regional lymphadenopathy in 72.7% (16/22). Two patients had metastasis to the liver and 1 patient to the bilateral adrenal glands. Three patients had coexisting malignancy. CONCLUSION Neuroendocrine tumors are rare in the stomach. On macroscopic presentation, they are usually seen as a large tumor of Borrmann type III with moderate enhancement. Perigastric fat stranding and regional lymphadenopathy are seen frequently. DISCLOSURE S.C.,D.C.,S.K.,W.L.,H.L.,J.L.:
    Radiological Society of North America 2005 Scientific Assembly and Annual Meeting; 11/2005
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    ABSTRACT: LEARNING OBJECTIVES 1) To learn the spectrum of multiphasic multi-detector row CT findings of cancer-mimicking inflammatory diseases of the pancreas. 2) To discuss how to differentiate cancer-mimicking inflammatory pancreatic diseases from true cancers. ABSTRACT CT is currently the single best imaging for pancreatic disorders. The most common multiphasic Multi-Detector row CT finding of pancreatic cancer is a hypoattenuating mass deforming the contour and size of the pancreas. Dilatation of the main pancreatic duct proximal to the mass is often noted. Mimickers showing these findings include benign tumors and inflammatory diseases. Inflammatory diseases such as focal pancreatitis are mistaken for pancreatic cancer, and some patients underwent unnecessary pancreaticoduodenectomy (Whipple operation). In this exhibit, we present a spectrum of multiphasic Multi-Detector row CT and pathologic findings of cancer-mimicking inflammatory diseases. We also discuss the key multi-detector row CT findings of cancer-mimicking pancreatitis that can suggest the possibility of a benign lesion.
    Radiological Society of North America 2005 Scientific Assembly and Annual Meeting; 11/2005