Baek Hyun Kim

Korea Railroad Research Institute, Sŏul, Seoul, South Korea

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Publications (40)30.5 Total impact

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    ABSTRACT: To investigate the relationship between a chronic obstructive pulmonary disease (COPD) candidate gene, based on a genomewide association study, and computed tomographic (CT) quantitative analysis; and to find a phenotype in the COPD candidate FAM13A gene. This study was conducted in subclinical male smokers between 2 groups with matched age and smoking status; 162 subjects (mean age, 58 years) with risk (CTGA, n = 85) and reference (TCAG, n = 77) diplotypes replicated through genomewide association study underwent chest CT for quantitative analysis of lungs and airways. We analyzed the measures in both the risk and reference groups using a 2-sample t test. Subjects with the risk CTGA diplotype had significantly higher total lung volume and emphysema index than the reference TCAG diplotype (P = 0.04). Mean lung density was significantly lower (P < 0.05) in the risk group. However, in the analysis of airways, wall area, luminal area, wall and lumen area ratio, and mean lung density on expiratory and inspiratory phases, no significant differences between the 2 groups were seen. There is a strong relationship between CT quantitative analysis and the COPD candidate gene. Furthermore, the CTGA diplotype was associated with emphysema among the phenotypes of COPD.
    Journal of computer assisted tomography 03/2014; · 1.38 Impact Factor
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    ABSTRACT: PURPOSE To determine and compare the reliability of 2D and 3D MRI interpretations in cervical neural foraminal stenosis. METHOD AND MATERIALS Forty-one patients with possible cervical spinal stenosis prospectively underwent cervical spine MRI in which the protocol included 2D T1 and T2-weighted fast spin-echo sequences in sagittal and axial planes, and a single sagittal 3D T2-weighted fast spin-echo sequence. The sagittal 3D data sets were reformatted at 1-mm slice thickness without a gap in 2 oblique sagittal plane (perpendicular to both right and left neural foramen). Three radiologists independently and blindly rated the severity of neural foraminal stenosis at C2-3 to C7-T1 with a 4-point scale, which was done in two separate 2D and 3D interpretation sessions with more than a month of interval. Kendall’s rank correlation test was used to characterize inter-reader reliability for categorical rating data. RESULTS Overall, interobserver agreement in ordinal ratings of neural foraminal stenosis was substantial in 2D (Kendall tau-b, 0.61-0.89) and substantial to excellent in 3D MRI (Kendall tau-b, 0.61-0.92). Interobserver agreement at C3-4 to C6-7 level was slightly higher in 3D protocol than in 2D protocol (Kendall tau-b: C3-4, 0.80 vs. 0.78; C4-5, 0.89 vs. 0.78; C5-6, 0.90 vs. 0.88; C6-7, 0.90 vs. 0.84). At C2-3 and C7-T1, reliability of reading of cervical neural foraminal stenosis did not differ between the two MR protocols (Kendall tau-b: C2-3, 0.61; C7-T1, 0.71). CONCLUSION We found that the MRI reading of cervical neural foraminal stenosis showed substantial interobserver agreement or above, and that 3D isotropic protocol slightly reduced the degree of interobserver variability. CLINICAL RELEVANCE/APPLICATION 3D isotropic MRI helps to increase the reliability in grading cervical neural foraminal stenosis.
    Radiological Society of North America 2013 Scientific Assembly and Annual Meeting; 12/2013
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    ABSTRACT: PURPOSE Contrast media excreted from the biliary tract is often seen in the stomach on Gadoxetic acid-enhanced MR cholangiography (Gadoxetic-MRC). The aim of this study is to evaluate the relationship between biliary excreted contrast media in stomach and the presence of bile reflux gastritis. METHOD AND MATERIALS A total of 111 consecutive patients who underwent both Gadoxetic-MRC and upper gastrointestinal endoscopy from May 2009 to April 2012 were included in this study. Two radiologists performed a blinded review of Gadoxetic-MRC set images consisting of axial and coronal images obtained 60 minutes after IV injection of contrast media. Presence of contrast media in duodenum and stomach was recorded along with the extension grade of reflux if the contrast media was seen in stomach: grade 1, antrum; grade 2, body; and grade 3, fundus. Endoscopic images were reviewed by an expert gastroenterologist blinded to the result of Gadoxetic-MRC. Sydney classification of gastritis was used to categorize gastritis if present. RESULTS Among a total of 111 patients, contrast media was present in the stomach on 60 minutes delayed images in 39 patients. Of these 39 patients, 13 patients had bile reflux gastritis and 3 patients showed bile in the stomach without evidence of erythematous mucosal changes. Of the 72 patients who did not show contrast media in the stomach, none of them had bile reflux gastritis and 2 patients showed bile stain in the stomach without evidence of erythematous mucosal changes. Bile reflux gastritis was significantly more frequent in patients with contrast media in the stomach on Gadoxetic MRC (13/39, 33.3%) than those without (0/72, 0%) (p < 0.001). However, there was no significant difference between bile reflux gastritis and the extension grade of reflux (grade 1: 2/12, grade 2: 4/11, grade 3: 7/16) (p = 0.335). CONCLUSION About a third of patients with biliary excreted contrast media in stomach had bile reflux gastritis which was more significantly frequent compared to those without. Biliary excreted contrast media in stomach on Gadoxetic-MRC obtained at 60 minutes could be an indication of the presence of bile reflux gastritis. CLINICAL RELEVANCE/APPLICATION Biliary excreted contrast media in stomach on Gadoxetic-MRC obtained at 60 minutes could be an indication of the presence of bile reflux gastritis.
    Radiological Society of North America 2013 Scientific Assembly and Annual Meeting; 12/2013
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    ABSTRACT: PURPOSE To describe the postoperative magnetic resonance (MR) appearance of the posterolateral corner (PLC) reconstruction of the knee and to correlate the MR findings with clinical examination. METHOD AND MATERIALS Postoperative MR examinations of 15 patients who underwent PLC reconstruction by PLC sling through the fibular tunnel using allograft from 1 to 36 months (mean 10 months) after the surgery were retrospectively reviewed. Graft shape, thickness, signal intensity of the anterior and posterior limbs of the sling were recorded. Peroneal nerve thickness and signal intensity were compared with preoperative MR images. The MR findings were correlated with the time since surgery and clinical examination. RESULTS All 15 grafts were intact without disruption and1 had biopsy-confirmed foreign body reaction. Five knees were unstable on physical examination at the time of MR imaging. Anterior limb of the sling appeared as elliptical shape (15 of 15) on axial images with mean thickness of 5.86 (SD ± 3.7) mm and posterior limb as crescent shape (11 of 15) with mean thickness of 3.23 (SD ±1.2) mm. Signal intensity of the overall graft sling was increased in 13 of 15 cases, and posterior limb showed same or higher grade signal increase compared with anterior limb in 10 of 13 cases. Signal increase in posterior limb was more prominent in graft with longer time interval since surgery (p<0.05). There was no correlation among joint stability, graft thickness, and graft signal intensity. Peroneal nerve thickening was present in 12 of 15 cases even though it was asymptomatic, and was a significant change compared with preoperative imaging (p<0.05). CONCLUSION In postoperative MR imaging of PLC reconstruction, increased signal intensity in posterior limb of the PLC sling appears to be related with time interval since surgery but not correlated with clinical stability, and peroneal nerve thickening may be an expected postoperative finding irrelevant to symptom. CLINICAL RELEVANCE/APPLICATION Postoperative MR imaging after the PLC reconstruction can depict the increased signal intensity of the graft and thickening of peroneal nerve.
    Radiological Society of North America 2013 Scientific Assembly and Annual Meeting; 12/2013
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    ABSTRACT: SUMMARY In ad hoc networks, directional antennas offer many benefits compared with classical omnidirectional antennas. Those include significant increases in spatial reuse, coverage range, and subsequently network capacity as a whole. Most of the proposed directional medium access control methods assume that all the nodes in the network have homogeneous antenna types. However, it is quite unusual that a sudden change will occur, and every laptop, palmtop, computer, and other similar device will be turned into a directional antenna holding device. There will always be a possibility of heterogeneous antenna used in the deployed nodes of the network. In this paper, we have proposed a medium access control protocol that deals with the new challenges introduced into heterogeneous networks in the form of deaf and hidden node problems. Using Optimized Network Engineering Tools 16.0, we have simulated three ad hoc network scenarios. These scenarios have different ratios of omnidirectional and directional nodes. We evaluated the performance of these scenarios by varying the ratio. We found that when we increase the directional nodes in the network, the performance increases. Copyright © 2013 John Wiley & Sons, Ltd.
    International Journal of Communication Systems 06/2013; · 1.11 Impact Factor
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    ABSTRACT: Axillary masses may represent various soft tissue tumors or lymphadenopathy. Neurofibromas are benign peripheral nerve sheath tumors and, while they are very uncommon, it is important to remember that neurogenic tumors arising from brachial plexus can develop in the axilla. We describe an axillary neurofibroma arising from the brachial plexus that presented with a "coffee bean sign" on sonography that distinguished it from axillary lymphadenopathy. © 2013 Wiley Periodicals, Inc. J Clin Ultrasound, 2013;
    Journal of Clinical Ultrasound 04/2013; · 0.70 Impact Factor
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    ABSTRACT: Aneurysms of the azygos vein are rare and can sometimes mimic a paratracheal or posterior mediastinal mass. It is important to confirm the diagnosis with radiologic tools before performing invasive procedures, which carry the risk of hemorrhage. Here, we present a case in a 79-year-old asymptomatic patient of an increasing azygos vein aneurysm that mimicked a growing paratracheal mass. Review of images obtained using various modalities, including dynamic magnetic resonance image (MRI), revealed that the image findings were suggestive of azygos vein aneurysm. Using this method, an exact diagnosis can be reached without resorting to invasive procedures.
    Balkan Journal of Medical Genetics 03/2013; 30(1):111-5. · 0.08 Impact Factor
  • Hyun Jeong Bae, Baek Hyun Kim, Do-Kyun Kwon
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    ABSTRACT: High-quality -silicon carbide (SiC) coatings are expected to prevent the oxidation degradation of carbon fibers in carbon fiber/silicon carbide (C/SiC) composites at high temperature. Uniform and dense -SiC coatings were deposited on carbon fibers by low-pressure chemical vapor deposition (LP-CVD) using silane () and acetylene () as source gases which were carried by hydrogen gas. SiC coating layers with nanometer scale microstructures were obtained by optimization of the processing parameters considering deposition mechanisms. The thickness and morphology of -SiC coatings can be controlled by adjustment of the amount of source gas flow, the mean velocity of the gas flow, and deposition time. XRD and FE-SEM analyses showed that dense and crack-free -SiC coating layers are crystallized in -SiC structure with a thickness of around 2 micrometers depending on the processing parameters. The fine and dense microstructures with micrometer level thickness of the SiC coating layers are anticipated to effectively protect carbon fibers against the oxidation at high-temperatures.
    Korean Journal of Materials Research 01/2013; 23(12).
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    ABSTRACT: Objective We aimed to compare diagnostic performance of gadoxetic-acid-enhanced-T1-weighted-MR cholangiography (MRC) with that of conventional T2-weighted-MRC in diagnosing biliary stone disease. Materials and Methods Ninety patients who underwent MRC for evaluation of biliary disease were included. Presence of stones in extrahepatic duct, gallbladder and intrahepatic duct, and presence of acute cholecystitis were evaluated. Sensitivity, specificity, and accuracy of biliary stone disease diagnosis in each biliary duct location according to each image sets were measured. Results There was no significant difference in diagnostic performance between two sets of MRC in diagnosing biliary stone disease. Conclusions Diagnostic performance of T1-MRC with gadoxetic-acid in diagnosing biliary stone disease is comparable to that of T2-MRC.
    Clinical imaging 01/2013; · 0.73 Impact Factor
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    ABSTRACT: PURPOSE To compare the diagnostic performance of Gadoxetic acid-enhanced MR cholangiography (Gadoxetic MRC) during the hepatobiliary phase with those of T2-weight MR cholangiography (T2 MRC) in the biliary stone disease. METHOD AND MATERIALS 157 consecutive patients were included in our study whom performed Gadoxetic-MRC and then underwent procedures which wcould confirm the biliary stone disease from May 2009 to April 2011. 26 patients with bile duct cancer and 39 patients with incomplete reference study were excluded. Two radiologists performed a blinded and independent review of two MRC sets which were T2-MRC set consisted of axial, coronal and thick slab reconstructed images and Gadoxetic-MRC set consisted of precontrast axial scan and axial, coronal and MIP reconstructed images obtained 60 minutes after contrast enhancement. We recorded the presence of stones in EHD, GB and IHD, and acute cholecystitis. We also recorded whether stone is represented as filling defect or luminal obstruction. Discordant findings were resolved by a consensus review with a third radiologist. The sensitivity, specificity, and accuracy of each image sets were evaluated. Inter-observer agreement was evaluated with kappa statistics. McNemar’s examination was used to compare the diagnostic accuracy between two MRC sets. A p value of less than 0.05 was considered significant. RESULTS Of the 92 patients, prevalences of EHD stone, GB stone, acute cholecystitis and IHD stone were 58.5% (24/41), 93.0% (66/71), 63.4% (45/71) and 68.8% (11/16). The diagnostic accuracies of T2-MRC for detecting EHD stone, GB stone, acute cholecystitis, and IHD stone were 90.2% (37/41), 81.7% (58/71), 94.4% (67/71), and 100% (16/16). And those of Gadoxetic-MRC were 87.8% (36/41), 78.9% (56/71), 94.4% (67/71), and 100% (16/16). (P=0.754, 0.774, 1 and 1). Among 21 EHD stones which were visible on Gadoxetic–MRC, 18 stones were represented as filling defect and 3 stones made luminal obstruction. Among 11 IHD stones, 6 stones were filling defect and 5 stones made luminal obstruction. Inter-observer agreement between both readers were good to excellent in T2-MRC and excellent in Gadoxetic-MRC. CONCLUSION There was no statistical significance in diagnostic accuracy of biliary stone disease between T2-MRC and Gadoxetic-MRC. CLINICAL RELEVANCE/APPLICATION Gadoxetic MRC usually represeents biliary stones as intraluminal filling defect. And its diagnostic performance is comparable to the T2-MRC
    Radiological Society of North America 2012 Scientific Assembly and Annual Meeting; 11/2012
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    ABSTRACT: PURPOSE To assess the value of contrast enhanced ultrasonography (CEUS) for diagnosing adhesive capsulitis and to correlate CEUS finding with MRI. METHOD AND MATERIALS Fourteen shoulder joints from seven patients with unilateral adhesive capsulitis (4 men, 3 women; mean age 51±12 years) who underwent contrast enhanced shoulder MRI on affected shoulder were prospectively examined by CEUS. All patients underwent CEUS on both shoulders and unaffected shoulder was enrolled as control. CEUS was performed after bolus administration of the contrast agent SonoVue (Bracco, Milan, Italy) with a dosage of 2.4ml followed by saline flush of 5ml. Enhancement of rotator interval was evaluated with peak enhancement time, visual enhancement score (0 to 2), and echo intensity (dB) change. Difference of degree of contrast enhancement between affected and unaffected shoulder was compared by conditional logistic regression. Correlation of contrast enhancement score between CEUS and MRI was assessed with weighted kappa value. RESULTS Mean peak enhancement time of CEUS was 28.9 ± 6.1 seconds in affected shoulder. Contrast enhancement of rotator interval was detectable in all affected shoulders (mean enhancement score of 1.4). Mean echo increase of rotator interval was 5.81 ± 1.89 dB in affected shoulder and 1.43 ± 1.4 dB in unaffected shoulder (p<0.05). Contrast enhancement score of CEUS was correlated with that of MRI (k=0.76). CONCLUSION CEUS was capable of demonstrating capsular inflammation in patients with adhesive capsulitis. CLINICAL RELEVANCE/APPLICATION CEUS could be a feasible imaging tool for evaluating patients with adhesive capsulitis.
    Radiological Society of North America 2012 Scientific Assembly and Annual Meeting; 11/2012
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    ABSTRACT: PURPOSE The purpose of this study was to evaluate the predictability of ankle US and MRI for determining the need for surgical fixation in isolated lateral malleolar fractures. METHOD AND MATERIALS Between February 2010 and March 2012, among consecutive 26 patients with isolated lateral malleolar fractures, 21 patients who underwent both ankle US and MRI were enrolled. (8 men and 13 women; mean 46.9 years, range 20-67 years). In the ankle US and MR studies, the integrity of the posterior tibiotalar ligament was analyzed with grading as follows: 0 (intact), 1 (partially ruptured), 2 (high-grade partially ruptured) or 3 (completely ruptured). Intraoperative valgus stress test was performed in all patients with medial clear space widening ≥ 4mm as the criteria of instability. Diagnostic performance of ankle US and MRI was evaluated by receiver operating characteristic analysis compared to the stress test. All patients with positive stress test underwent surgical treatment. RESULTS Nine patients with positive stress test underwent surgical treatment and 12 patients with negative stress test underwent conservative management. For ankle US and MRI, the sensitivity, specificity, average area under the curve were 0.8, 0.73, 0.868, and 0.9, 0.73, 0.873 with an optimal cut-off value of grade 2, respectively. When ankle instability was determined as over grade ligament tear, the sensitivity, specificity, positive predictive value, negative predictive value and diagnostic accuracy of ankle US and MRI were 0.9, 0.73, 0.75, 0.89, 0.81 and 0.8, 0.73, 0.73, 0.8, 0.76, respectively. When the ankle instability was determined as over grade 3 ligament tear, those of ankle US and MRI were 0.4, 1.0, 1.0, 0.65, 0.71 and 0.5, 1.0, 1.0, 0.69, 0.76, respectively. Diagnostic accuracy of ankle US was higher than MRI when ankle instability was determined as over grade 2 ligament tear. CONCLUSION Both ankle MRI and US are predictable for the deltoid ligament injury in isolated lateral malleolar fracture. Both modalities can be used for preoperative determining whether surgical treatment is needed or not in the patients with isolated lateral malleolar fracture, in the place of intraoperative stress test. CLINICAL RELEVANCE/APPLICATION Ankle MRI and US can be used in the place of intraoperative stress test.
    Radiological Society of North America 2012 Scientific Assembly and Annual Meeting; 11/2012
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    ABSTRACT: Dorsal sural neuropathy occurs infrequently as a result of compression of the nerve due to various etiologies.We describe a 52-year-old diabetic woman with dorsal sural neuropathy. The diagnosis was based on clinical, electrophysiological, ultrasonographic, and magnetic resonance imaging (MRI) findings. This case report demonstrates the usefulness of electrophysiological and imaging studies, including ultrasonography, in the diagnosis of dorsal sural neuropathy. Muscle Nerve 46: 597-600, 2012.
    Muscle & Nerve 10/2012; 46(4):597-600. · 2.31 Impact Factor
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    ABSTRACT: A retrospective analysis was performed based on the medical records and imaging studies of 16 wrists (14 patients) with isolated partial intercarpal ligament tears (scapholunate ligament: 6 wrists, lunotriquetral ligament, 10 wrists) treated with arthroscopic debridement and thermal shrinkage. Three wrists had Geissler grade 1 tears and 13 wrists had grade 2 tears. Mean follow-up was 52.8 months. Overall pain visual analog scale scores improved significantly (P<.05) at rest and during activities of daily living and heavy manual work. Mean flexion-extension arc was 136.5°. Mean postoperative grip strength was 106 lb, which was significantly better than preoperative grip strength. Mean modified Mayo wrist score was 70 preoperatively and 94.7 postoperatively, a significant improvement. Overall functional outcomes according to the modified Mayo wrist score were rated as excellent in 13 wrists and good in 3. No patient had radiographic evidence of instability or arthritic changes. The scapholunate and lunotriquetral intervals in all patients were less than 3 mm on neutral and pronation grip radiographs. On lateral radiographs, no signs of intercalated segmental instability were seen, with a mean scapholunate angle of 55.3°. The results of this study suggest that arthroscopic debridement and thermal shrinkage provide symptomatic pain relief and prevention of intercarpal instability for a significant period of time in patients with partial intercarpal ligament tear.
    Orthopedics 08/2012; 35(8):e1204-9. · 1.05 Impact Factor
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    ABSTRACT: The present paper reports and discusses a case of sacral lipomyelomeningocele with an anomalous long bone articulating with the left iliac bone in a 40-year-old female. That patient had a monozygotic twin sister who had normal spine. The findings were incidental during an evaluation for a urinary tract infection. The computed tomography (CT) and magnetic resonance (MR) images revealed sacral dysraphism, lipomyelomeningocele, tethered spinal cord, and profound subcutaneous fat in the sacrococcygeal region. In addition, an anomalous bony strut was demonstrated on the posterior aspect of the sacrum, covering the sacral defect and the associated lipomyelomeningocele. The 3-D CT images of the anomalous bone associated with the sacral lipomyelomeningocele and the putative embryologic process are presented with a review of the literature.
    Congenital Anomalies 06/2012; 52(2):115-8.
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    ABSTRACT: To demonstrate the imaging findings of biliopancreatic and pancreatico-biliary reflux in patients with anomalous union of the pancreatico-biliary duct (AUPBD) on gadoxetic acid-enhanced functional magnetic resonance cholangiography (fMRC). This study included six consecutive patients (two men and four women; mean age 47.5 years) with AUPBD. All subjects underwent endoscopic retrograde cholangiopancreatography (ERCP); one subject also underwent bile sampling of the common bile duct (CBD) to measure the amylase level because his gadoxetic acid-enhanced fMRC images showed evidence of pancreatico-biliary reflux of pancreatic secretions. Of the five patients with choledochal cysts, four underwent pylorus-preserving pancreaticoduodenectomy. The five cases of choledochal cysts were classified as Todani classification I. In three of the six patients with AUPBD, injected contrast media reached the distal CBD and pancreatic duct on delay images, suggesting biliopancreatic reflux. In two of these six patients, a band-like filling defect was noted in the CBD on pre-fatty meal images, which decreased in size on delayed post-fatty meal images, suggesting pancreatico-biliary reflux of pancreatic secretions, and the bile sampled from the CBD in one patient had an amylase level of 113,000 IU/L. In one of the six patients with AUPBD, contrast media did not reach the distal CBD due to multiple CBD stones. Gadoxetic acid-enhanced fMRC successfully demonstrated biliopancreatic reflux of bile and pancreatico-biliary reflux of pancreatic secretions in patients with AUPBD with and without choledochal cysts.
    World Journal of Gastroenterology 03/2012; 18(9):952-9. · 2.55 Impact Factor
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    ABSTRACT: To investigate the significance of the cortex-hilum (CH) area ratio and longitudinal-transverse (LT) axis ratio and the blood flow pattern for diagnosis of metastatic axillary lymph nodes by ultrasound in breast cancer patients. From October 2005 to July 2006, we prospectively evaluated axillary nodes with ultrasound in 205 consecutive patients who had category 4B, 4C or 5 breast lesions according to the Breast Imaging Reporting and Data System-Ultrasound (BI-RADS-Ultrasound®). Among the 205, there were 24 patients who had pathologic verification of breast cancer and axillary lymph node status. For a total of 80 axillary nodes we measured the areas of the cortex and hilum of lymph nodes and calculated the area ratio. We also measured the length of the longitudinal and transverse axis of the lymph nodes and calculated the length ratio. We evaluated the blood flow pattern on power Doppler imaging and classified each lymph node into a central or peripheral pattern. Diagnostic performance was analyzed according to positive criteria for lymph node metastasis (CH area ratio >2, LT axis ratio <2, peripheral type on power Doppler imaging). The sensitivity of the CH area ratio was superior to that of the LT axis ratio (94.1% vs. 82.3%, p=0.031) and to that of the blood flow pattern (94.1% vs. 29.4%, p=0.009). For specificity, all three evaluating parameters had high values (89.1-95.6%) and no significant differences were found (p=0.121). The CH area ratio had a better positive predictive value than the LT axis ratio (94.1% vs. 80.0%, p=0.030) and power Doppler imaging (94.1% vs. 66.6%, p=0.028). For the negative predictive value, the CH area ratio was superior to the LT axis ratio (95.6% vs. 86.6%, p=0.035) and the blood flow pattern (95.6% vs. 63.0%, p=0.027). We recommend the CH area ratio of an axillary lymph node on ultrasound as a quantitative indicator for the classification of lymph nodes. The CH area ratio can improve diagnostic performance when compared with the LT axis ratio or blood flow pattern.
    Journal of breast cancer. 03/2012; 15(1):65-70.
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    ABSTRACT: PURPOSE To present and evaluate the initial clinical experiences of ultrasound-guided perineural steroid injection for the treatment of carpal tunnel syndrome. METHOD AND MATERIALS From April 2009 to April 2010, we performed ultrasound-guided perineural steroid injection for the treatment of carpal tunnel syndrome in 16 cases of 10 patients. There were 9 female and 1 male patients with mean age of 54.2 years-old (range 33 ~ 72 years). Three were 6 patients with bilateral carpal tunnel syndrome. All patients were diagnosed by clinical symptoms/ signs and by eledctrodiagnostic examination, and the duration of symptom was between 3 to 120 months (mean 23.6 months) before injection. Longitudinal proximal-to-distal needle insertion was done under real time ultrasound guidance by 1 musculoskeletal radiologist. Perineural steroid injection was done along the outer epineurium and adjacent connective tissue of the median nerves. Less than total 1.5mL steroid mixture (1mL 40mg Triamcinolon + 0.5mL 0.25% Ropivacaine) was injected into each median nerve. RESULTS Nine of 10 patients (90%) showed symptom improvement after ultrasound-guided perineural steroid injection. One patient showed no interval change in the symptom after injection. The duration of symptom-improved/ free period after injection was between 6 weeks to 14 months (mean 25 weeks). Three patients (30%) showed symptom recurrence in 6 to 16 weeks (mean 12 weeks) after injection. There was no complication. CONCLUSION Ultrasound may be used efficiently in the guidance of perineural steroid injection for the treatment of carpal tunnel syndrome. And radiologist can perform easily the ultrasound-guided perineural steroid injection for the treatment of carpal tunnel syndrome. CLINICAL RELEVANCE/APPLICATION Radiologists can do treat the patients with carpal tunnel syndrome by doing perineural steroid injection under ultrasound guidance, efficiently.
    Radiological Society of North America 2011 Scientific Assembly and Annual Meeting; 11/2011
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    ABSTRACT: PURPOSE We aimed to demonstrate the usefulness of MDCT in early detection of cortical collapse in osteonecrosis of femoral head, compared with hip MRI. We also aimed to evaluate and compare the extent of osteonecrosis on both MDCT and MRI according to Ficat and Arlet staging, using modified Kerboul method. METHOD AND MATERIALS From January, 2005 to December, 2009, total 281 hips of 183 patients were evaluated in this study, which underwent both MDCT and MRI. For the evaluation of cortical collapse, we reviewed and staged axial and coronal reconstructed MDCT images and axial and coronal MR images based on Ficat and Arlet staging system and compared the results of MDCT and MRI by Chi-square test. Excluding 91 hips without available sagittal MR images, the extent of osteonecrosis was evaluated in 190 hips on coronal and sagittal MDCT and MR images, using modified Kerboul method, and analyzed by Student T-test, one-way ANOVA, and Pearson correlation test. RESULTS Among 281 hips, 55 cases of Ficat and Arlet stage 3 and 25 cases of stage 4 on MDCT were understaged as stage 2 (51.9%) and stage 3 (46.3%) on MRI, respectively. Seventeen hips of stage 4 on MDCT were underestimated as stage 2 on MRI (10%). Staging on MRI based on cortical collapse was downgraded compared with that of MDCT (Chi-square test, p=.000). In 190 hips, each measured angle by Kerboul method was not different between MDCT and MRI (Paired T-test, p=.752). However, measured angle using Kerboul method differed on both MDCT and MRI (one-way ANOVA, p=.000) according to Ficat and Arlet stage. There was a positive correlation between Ficat and Arlet stage and measured angle by Kerboul method on both MDCT (Pearson correlation test, γ=.275, p=.000) and MRI (Pearson correlation test, γ=.214, p=.003). CONCLUSION MDCT may be more useful for the detection of subchondral collapse or cortical flattening than MRI in osteonecrosis of hip. Using modified Kerboul method, the prediction of cortical collapse may be possible on MDCT similarly to MRI. CLINICAL RELEVANCE/APPLICATION Using MDCT, staging and prediction of prognosis in osteonecrosis of hip may be more easier and reproducible in practice than MRI.
    Radiological Society of North America 2010 Scientific Assembly and Annual Meeting; 11/2010
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    ABSTRACT: The risk of complications and discomfort in patients who undergo prolonged infusion of a thrombolytic agent is significant when conventional catheter-directed thrombolysis is used to treat lower extremity deep vein thrombosis (DVT). To evaluate the feasibility and safety of single-session endovascular treatment for symptomatic lower extremity DVT. Single-session endovascular treatment for lower extremity DVT was performed on 29 limbs in 26 patients diagnosed with acute DVT in our institution. Nine patients were male and 17 female, with a mean age of 64 years (range 28-82 years). At 5-10 min after the locoregional injection of the thrombolytic agent (urokinase) via a 5-Fr catheter to soften the thrombus, aspiration thrombectomy was performed with a large-bore sheath. In patients with an underlying anatomical stenosis or obstruction, combined angioplasty with or without stent placement was performed immediately after the complete removal of the thrombus. We then evaluated the technical and clinical outcomes of the procedure, along with any complications or recurrences of DVT. Technical success was achieved in 24 procedures (82.8%) of single-session endovascular treatment for lower extremity DVT, and clinical success was achieved in 22 (75.9%) of these single-session procedures. Additional catheter-directed thrombolysis procedures were performed on five limbs after repeated aspiration thrombectomies failed to completely remove thrombi in those limbs. Stenotic or occlusive lesions were revealed in 24 limbs and percutaneous angioplasty procedures with or without stent placement were performed in these cases. No major complications resulted from the procedure. Single-session endovascular treatment is a feasible technique that provides acceptable technical and clinical success with excellent safety for treating symptomatic lower extremity DVT.
    Acta Radiologica 04/2010; 51(3):248-55. · 1.33 Impact Factor

Publication Stats

116 Citations
30.50 Total Impact Points

Institutions

  • 2013
    • Korea Railroad Research Institute
      Sŏul, Seoul, South Korea
  • 2001–2012
    • Korea University
      • • Department of Radiology
      • • College of Medicine
      Sŏul, Seoul, South Korea
  • 2009
    • Kangwon National University Hospital
      South Korea
  • 2007
    • Yonsei University Hospital
      • Department of Internal Medicine
      Sŏul, Seoul, South Korea
  • 2004
    • Konkuk University
      Sŏul, Seoul, South Korea