1.Use of Methyl-alpha-D-glucopyranoside Test for Species Identification of Vancomycin Resistant Enterococci.
Mi Na KIM ; Heung Sub SUNG ; Jun Seok PARK ; Chik Hyun PAI
Korean Journal of Clinical Microbiology 1999;2(1):71-76
BACKGROUND: The precise identification of Enterococcus gallinarum and E. casseliflavus has assumed additional importance in clinical microbiology due to the intrinsic low-level resistance to vancomycin and the difficulty in differentiating them from E. faecium or E. faecalis, which are frequently found to be clinically significant vancomycin resistant enterococci(VRE). We evaluated the usefulness of Methyl-alpha-D-glucopyranoside(MDG) test for accurate species identification among them. METHODS: A total of 23 enterococci isolates including 18 clinical isolates of VRE from Nov 1997 to Aug 1998 and 5 VRE strains which had previously been reported as E. faecalis (2), E. faecium(2), E. avium(1) carrying vanC were tested for acidification of MDG. MDG test was done using 1% MDG in phenol red broth base and yellow coloration was interpreted as positive after 1 and 2 days of incubation at 35 degrees C. MDG results were compared with species identification by MicroScan Pos Combo type 6 (Dade, US A), motility test, pigment production, and PCR results of vanA, vanB, vanC1, vanC2/C3. RESULTS: Vancomycin resistance of 23 strains were genotyped as 7 strains of vanA, 12 strains of vanC1, 4 strains of vanC2/C3. MicroScan identified 7 vanA VRE as E. faecalis(1) and E. faecium(6), 12 VRE carrying vanC1 as E. faecalis(3), E. faecium(8) and E. avium(1), and 4 VRE carrying vanC2/C3 as E faecalis(3) and E. avium(1). Sixteen vanC VRE strains were all positive for MDG test and only 8(50%) of the 16 strains were motile. Yellow pigment were detected in all 4 vanC2/C3 VRE but only after a careful examination with a prolonged incubation. Seven vanA VRE were all negative in MDG tests, motility test and pigment production. CONCLUSIONS: MicroScan system plus motility and pigment production test was not able to differentiate reliably E. gallinarum and E. casseliflavus from E. faecalis and E. faecium. The MDG test was shown to be superior to motility test in differentiating those from E. faecalis and E. faecium. We conclude that the MDG test should be included for identifcation of VRE.
Enterococcus
;
Phenolsulfonphthalein
;
Polymerase Chain Reaction
;
Vancomycin Resistance
;
Vancomycin*
2.Matchstick-Shaped Bone Grafting for the Treatment of Distal Phalangeal Nonunion.
Heung Sub SHIN ; Hyo Kon KIM ; Sung Han HA ; Sun O YU ; Gi Jun LEE
Journal of the Korean Society for Surgery of the Hand 2012;17(1):1-8
PURPOSE: The purpose of this study was to evaluate clinical and radiological results after osteosynthesis of distal phalangeal nonunion with bone defect by using matchstick-shaped bone graft. MATERIALS AND METHODS: Fifteen distal phalangeal nonunions were treated with osteosynthesis using matchstick-shaped bone graft from September, 2009 to October, 2010. The mean age of patients was 36.1 years (range: 15 to 56 years). This study included 4 women and 10 men. The mean duration of follow-up was 16.8 months (range: 12 to 20 months). We evaluated radiographs, and measured postoperative visual analogue scale (VAS) score and pinch power. RESULTS: Union was achieved in all cases at a mean of postoperative 5.5 weeks (range: 4 to 6 weeks). The mean VAS score improved from 7.25 (range: 5 to 9) to 1.0 (range: 0 to 2) postoperatively. The mean postoperative pinch power was 7.75 lbs (range: 4 to 13 lbs) compared to opposite pinch power of 9.63 lbs (range: 5 to 15 lbs). There was no scar problem, pinch pain and other complication. CONCLUSION: Steosynthesis of distal phalageal nonunion with bone defect by using matchstick-shaped bone graft is technically feasible and simple in that it does not need volar incision and debridement. It is considered as an effective treatment option in distal phalangeal nonunion with bone defect.
Bone Transplantation
;
Cicatrix
;
Debridement
;
Female
;
Follow-Up Studies
;
Humans
;
Male
;
Transplants
3.Reconstruction of the Finger Nail Using Microsurgical Composite Toe Nail Transfer.
Gi Jun LEE ; Sung Han HA ; Hyo Kon KIM ; Heung Sub SHIN ; Sun O YOU
Journal of the Korean Society for Surgery of the Hand 2011;16(1):1-8
PURPOSE: The presence of normal fingernail is important for the hand function and cosmetic appearance. We studied the results of the microsurgical reconstruction of the defected fingernail using composite toenail transfer. MATERIALS AND METHODS: From March of 2004 to May of 2009, eleven fingernails were reconstructed using microsurgical composite toenail transfer in 10 patients with a mean age of 27 years (range, 13 to 47 years). There were three thumbs, five index fingers, and three long fingers. Whole fingernail was destructed in three cases and remaining eight cases had partial nail defect. Toenail was grafted from great toe in eight cases and from second toe in three cases. Five cases were harvested as an osteoonychocutaneous flap, two as a endoosteoonychocutaneous flap and four as an onychocutaneous flap. RESULTS: All cases survived without any tissue necrosis. One arterial obstruction had occurred one day after surgery, which was resolved by repeated decompression and reanastomosis of the artery. All fingernails regenerated successfully. According to the rating system including assessment of shape, size and thickness of nail, nail pinch, pain, and patient's satisfaction, ten cases were rated as excellent and one as good. All patient's were satisfied with their hand function and appearance. CONCLUSION: Microsurgical composite toenail transfer can be an acceptable surgical reconstruction for the fingernail defect after trauma, providing satisfactory hand functions and cosmetic appearance.
Arteries
;
Cosmetics
;
Decompression
;
Fingers
;
Hand
;
Humans
;
Nails
;
Necrosis
;
Thumb
;
Toes
;
Transplants
4.Dual Miniplate Fixation for the Comminuted Fractures of the Hand.
Heung Sub SHIN ; Hyo Kon KIM ; Sung Han HA ; Sun O YU ; Gi Jun LEE
Journal of the Korean Society for Surgery of the Hand 2011;16(2):78-84
PURPOSE: The objective of this study was to evaluate clinical results of dual miniplate fixation for comminuted or periarticular fractures of the hand. MATERIALS AND METHODS: Twenty cases in 18 patients who had comminuted or periarticular fractures of metacarpal or phalangeal bones were treated with dual miniplate fixation from April, 2007 to May, 2009. The mean followed up period was 14.7 months. Our study included comminuted or periarticular fractures which were difficult to keep the fixation by pining or single plating. We evaluated radiologic bony union, angular or rotational deformity, extensor tendon irritaion and total arc of motion. RESULTS: Bony union was achieved successfully after primary dual miniplate fixationin in 12 cases. In 7 cases with a nonunion following previous operative fixation, bony union was obtained by dual miniplate fixation and bone grafting. In one case who had received primary dual plate fixation, nonunion occurred due to massive bone defect. Bony union was obtained by secondary dual plate fixation and bone grafting. Postoperative rotational deformity, angular deformity and irritation symptom were not observed in all cases. Functionally acceptable range of active motion was restored by way of early active motion. CONCLUSION: The dual miniplate fixation is one of the useful method for comminuted metacarpal or phalangeal fractures which cannot obtain firm fixation by other methods.
Bone Transplantation
;
Congenital Abnormalities
;
Fractures, Comminuted
;
Hand
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Humans
;
Tendons
5.Metabolic Changes on Occipital Cortex during Visual Stimulation with Functional MR Imaging and 1H Spectroscopy.
Tae KIM ; Tae Suk SUH ; BO Young CHOE ; Sung Eun KIM ; Heung Kye LEE ; Kyung Sub SHINN
Journal of the Korean Society of Magnetic Resonance in Medicine 1999;3(1):47-52
PURPOSE: The purpose of this study was aimed to evaluate BOLD(blood oxygen level dependent) contrast fMRI(function MR imaging) in the occipital lobe and to compare with the metabolic changes based on 1H MRS(MR spectroscopy) and MRSI(MR spectroscopic imaging) before and after visual stimulation MATERIALS AND METHODS: Healthy human volunteers(eight males and two females with 24-30 year age) participated in this study. All of the BOLD fMRI were acquired on a 1.5T MR with EPI during supervised visual stimulation in the occipital lobe. The red flicker with 8Hz was used for visual stimulation. After imaging acquisition, the MR images were transferred into unix workstation and processed with home made analysis software based on the correlation coefficient method. Proton MRS data sets were acquired from the same location based on the activation map. MRSI(magnetic resonance spectroscopic imaging) was also acquired to analyze the lactate changes before and after stimulation. RESULTS: The activation maps were successfully produced by BOLD effect due to visual stimulation. NAA(N-acetyle aspartate)/Cr(creatine) ratio varied only from 1.790.28 to 1.880.20 in activation area before and after stimulation. However, the signal intensity of lactate was elevated 9.484.38times higher than before activation. Lactate metabolite images were consistent with the activation maps. CONCLUSION: The BOLD contrast fMRI is enough sensitive to detect the activated area in human brain during the visual stimulation. Lactate metabolite map presents the evidence of lactate elevation on the same area of activation.
Brain
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Dataset
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Female
;
Humans
;
Lactic Acid
;
Magnetic Resonance Imaging*
;
Male
;
Occipital Lobe
;
Oxygen
;
Photic Stimulation*
;
Protons
;
Spectrum Analysis*
6.Amifostine ameliorates recognition memory defect in acute radiation syndrome caused by relatively low-dose of gamma radiation.
Hae June LEE ; Joong Sun KIM ; Myoung Sub SONG ; Heung Sik SEO ; Miyoung YANG ; Jong Choon KIM ; Sung Kee JO ; Taekyun SHIN ; Changjong MOON ; Sung Ho KIM
Journal of Veterinary Science 2010;11(1):81-83
This study examined whether amifostine (WR-2721) could attenuate memory impairment and suppress hippocampal neurogenesis in adult mice with the relatively low-dose exposure of acute radiation syndrome (ARS). These were assessed using object recognition memory test, the terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling assay, and immunohistochemical markers of neurogenesis [Ki-67 and doublecortin (DCX)]. Amifostine treatment (214 mg/kg, i.p.) prior to irradiation significantly attenuated the recognition memory defect in ARS, and markedly blocked the apoptotic death and decrease of Ki-67- and DCX-positive cells in ARS. Therefore, amifostine may attenuate recognition memory defect in a relatively low-dose exposure of ARS in adult mice, possibly by inhibiting a detrimental effect of irradiation on hippocampal neurogenesis.
Acute Radiation Syndrome/drug therapy/*immunology/psychology
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Amifostine/*pharmacology/therapeutic use
;
Animals
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Apoptosis/immunology
;
Gamma Rays/*adverse effects
;
Hippocampus/immunology
;
Immunohistochemistry
;
In Situ Nick-End Labeling
;
Male
;
Memory/*radiation effects
;
Mice
;
Mice, Inbred ICR
;
Neurogenesis/immunology
;
Radiation-Protective Agents/*pharmacology/therapeutic use
7.Liver-to-Spleen Volume Ratio Automatically Measured on CT Predicts Decompensation in Patients with B Viral Compensated Cirrhosis
Ji Hye KWON ; Seung Soo LEE ; Jee Seok YOON ; Heung-Il SUK ; Yu Sub SUNG ; Ho Sung KIM ; Chul-min LEE ; Kang Mo KIM ; So Jung LEE ; So Yeon KIM
Korean Journal of Radiology 2021;22(12):1985-1995
Objective:
Although the liver-to-spleen volume ratio (LSVR) based on CT reflects portal hypertension, its prognostic role in cirrhotic patients has not been proven. We evaluated the utility of LSVR, automatically measured from CT images using a deep learning algorithm, as a predictor of hepatic decompensation and transplantation-free survival in patients with hepatitis B viral (HBV)-compensated cirrhosis.
Materials and Methods:
A deep learning algorithm was used to measure the LSVR in a cohort of 1027 consecutive patients (mean age, 50.5 years; 675 male and 352 female) with HBV-compensated cirrhosis who underwent liver CT (2007–2010).Associations of LSVR with hepatic decompensation and transplantation-free survival were evaluated using multivariable Cox proportional hazards and competing risk analyses, accounting for either the Child-Pugh score (CPS) or Model for End Stage Liver Disease (MELD) score and other variables. The risk of the liver-related events was estimated using Kaplan-Meier analysis and the Aalen-Johansen estimator.
Results:
After adjustment for either CPS or MELD and other variables, LSVR was identified as a significant independent predictor of hepatic decompensation (hazard ratio for LSVR increase by 1, 0.71 and 0.68 for CPS and MELD models, respectively; p < 0.001) and transplantation-free survival (hazard ratio for LSVR increase by 1, 0.8 and 0.77, respectively; p < 0.001). Patients with an LSVR of < 2.9 (n = 381) had significantly higher 3-year risks of hepatic decompensation (16.7% vs. 2.5%, p < 0.001) and liver-related death or transplantation (10.0% vs. 1.1%, p < 0.001) than those with an LSVR ≥ 2.9 (n = 646). When patients were stratified according to CPS (Child-Pugh A vs. B–C) and MELD (< 10 vs. ≥ 10), an LSVR of < 2.9 was still associated with a higher risk of liver-related events than an LSVR of ≥ 2.9 for all Child-Pugh (p ≤ 0.045) and MELD (p ≤ 0.009) stratifications.
Conclusion
The LSVR measured on CT can predict hepatic decompensation and transplantation-free survival in patients with HBV-compensated cirrhosis.
8.Deep Learning Algorithm for Automated Segmentationand Volume Measurement of the Liver and Spleen UsingPortal Venous Phase Computed Tomography Images
Yura AHN ; Jee Seok YOON ; Seung Soo LEE ; Heung-Il SUK ; Jung Hee SON ; Yu Sub SUNG ; Yedaun LEE ; Bo-Kyeong KANG ; Ho Sung KIM
Korean Journal of Radiology 2020;21(8):987-997
Objective:
Measurement of the liver and spleen volumes has clinical implications. Although computed tomography (CT)volumetry is considered to be the most reliable noninvasive method for liver and spleen volume measurement, it has limitedapplication in clinical practice due to its time-consuming segmentation process. We aimed to develop and validate a deeplearning algorithm (DLA) for fully automated liver and spleen segmentation using portal venous phase CT images in variousliver conditions.
Materials and Methods:
A DLA for liver and spleen segmentation was trained using a development dataset of portal venousCT images from 813 patients. Performance of the DLA was evaluated in two separate test datasets: dataset-1 which included150 CT examinations in patients with various liver conditions (i.e., healthy liver, fatty liver, chronic liver disease, cirrhosis,and post-hepatectomy) and dataset-2 which included 50 pairs of CT examinations performed at ours and other institutions.The performance of the DLA was evaluated using the dice similarity score (DSS) for segmentation and Bland-Altman 95%limits of agreement (LOA) for measurement of the volumetric indices, which was compared with that of ground truth manualsegmentation.
Results:
In test dataset-1, the DLA achieved a mean DSS of 0.973 and 0.974 for liver and spleen segmentation, respectively,with no significant difference in DSS across different liver conditions (p = 0.60 and 0.26 for the liver and spleen, respectively).For the measurement of volumetric indices, the Bland-Altman 95% LOA was -0.17 ± 3.07% for liver volume and -0.56 ± 3.78%for spleen volume. In test dataset-2, DLA performance using CT images obtained at outside institutions and our institutionwas comparable for liver (DSS, 0.982 vs. 0.983; p = 0.28) and spleen (DSS, 0.969 vs. 0.968; p = 0.41) segmentation.
Conclusion
The DLA enabled highly accurate segmentation and volume measurement of the liver and spleen using portalvenous phase CT images of patients with various liver conditions.
9.Development of TEM Head-size Resonator for 3T MRI Head Coil.
Seung Hoon HA ; Bo Young CHOE ; Yong Sik KIM ; Sung Eun KIM ; Tae Suk SUH ; Hyong Koo LEE ; Kyung Sub SHINN ; Heung Kyu LEE
Journal of the Korean Society of Magnetic Resonance in Medicine 1999;3(3):232-238
PURPOSE: To apply a distributed circuit theory, to develop a head-size transverse electromagnetic(TEM) resonator coil for a home-built 3T whole-body MRI system and to report an efficiency of the coil. MATERIALS AND METHODS: The dimension of TEM resonator with 16 cavity element, the diameter of copper rod was 0.63cm and its length was 13.75cm. As raw materials, the purity of copper rod was 98% and the dielectric constant of teflon was 2.08. RESULTS: The TEM head-size resonator with 16cavity elements exhibiting 9-mode resonances was robust to the surrounding influences owing to the self-shielding structure. The isolation of quadrature with a human brain was 364 and the ratio of Q(unloaded/Q(loaded) was 2.9. CONCLUSION: It was successfully demonstrated that the TEM head-size resonator with high Q factor can provide high quality MR images at 3T MRI system. Also, the TEM resonator coil has an advantage for a fine tune with length adjustment of each cavity elements. Thus, it is expected that the TEM resonator at 3T, even higher field could be used in the clinical and research studies in near future.
Brain
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Copper
;
Head*
;
Humans
;
Magnetic Resonance Imaging*
;
Polytetrafluoroethylene
10.Deep Learning-Based Assessment of Functional Liver Capacity Using Gadoxetic Acid-Enhanced Hepatobiliary Phase MRI
Hyo Jung PARK ; Jee Seok YOON ; Seung Soo LEE ; Heung-Il SUK ; Bumwoo PARK ; Yu Sub SUNG ; Seung Baek HONG ; Hwaseong RYU
Korean Journal of Radiology 2022;23(7):720-731
Objective:
We aimed to develop and test a deep learning algorithm (DLA) for fully automated measurement of the volume and signal intensity (SI) of the liver and spleen using gadoxetic acid-enhanced hepatobiliary phase (HBP)-magnetic resonance imaging (MRI) and to evaluate the clinical utility of DLA-assisted assessment of functional liver capacity.
Materials and Methods:
The DLA was developed using HBP-MRI data from 1014 patients. Using an independent test dataset (110 internal and 90 external MRI data), the segmentation performance of the DLA was measured using the Dice similarity score (DSS), and the agreement between the DLA and the ground truth for the volume and SI measurements was assessed with a Bland-Altman 95% limit of agreement (LOA). In 276 separate patients (male:female, 191:85; mean age ± standard deviation, 40 ± 15 years) who underwent hepatic resection, we evaluated the correlations between various DLA-based MRI indices, including liver volume normalized by body surface area (LV BSA), liver-to-spleen SI ratio (LSSR), MRI parameter-adjusted LSSR (aLSSR), LSSR x LV BSA, and aLSSR x LV BSA, and the indocyanine green retention rate at 15 minutes (ICG-R15), and determined the diagnostic performance of the DLA-based MRI indices to detect ICG-R15 ≥ 20%.
Results:
In the test dataset, the mean DSS was 0.977 for liver segmentation and 0.946 for spleen segmentation. The BlandAltman 95% LOAs were 0.08% ± 3.70% for the liver volume, 0.20% ± 7.89% for the spleen volume, -0.02% ± 1.28% for the liver SI, and -0.01% ± 1.70% for the spleen SI. Among DLA-based MRI indices, aLSSR x LV BSA showed the strongest correlation with ICG-R15 (r = -0.54, p < 0.001), with area under receiver operating characteristic curve of 0.932 (95% confidence interval, 0.895–0.959) to diagnose ICG-R15 ≥ 20%.
Conclusion
Our DLA can accurately measure the volume and SI of the liver and spleen and may be useful for assessing functional liver capacity using gadoxetic acid-enhanced HBP-MRI.