• The Korean Journal of Nuclear Medicine
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• v.30 no.1
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• pp.86-94
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• 1996

Coronary angiography should be performed to verify the patency of bypass graft if coronary artery disease is said to be surgically corrected. Rest/stress myocardial SPECT could be used as a noninvasive alternative to prove patency of bypass graft and functional significance of graft patency by showing improvement of rest perfusion and perfusion reserve after operation. We evaluated the outcome of coronary artery bypass graft surgery by comparing rest/dipyridamole-stress myocardial SPECT before and after operation. Myocardial SPECT were performed $19{\pm}23$ days before and $108{\pm}19$ days after operation in 44 patients(M:F=25:19). Segmental perfusion were scored with 0(normal) to 3(defect) independently for each image set of rest and stress. Perfusion scores were compared between pre and postoperative images. Rest/stress images of pre and post-operative SPECT were compared in paired sets. Postoperative change of perfusion was determined as no change, improvement or aggravation for each artery territory. Postoperative outcome of patients were analyzed. Overall, 74%(158 segments) of 215 segments which had perfusion decrease before operation showed improvement. Among 60 artery territories, 37 territories(62%) improved. Among 42 patients with perfusion decrease in preoperative SPECT, 21 patients(47%) improved after operation. Severe persistent defects improved in 43%(6/14). We concluded that bypass surgery improved myocardial perfusion in dipyridamole stress induced or persistent decrease and that rest/stress myocardial SPECT could be used as a guide for which artery should be operated.

• The Korean Journal of Nuclear Medicine
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• v.28 no.2
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• pp.172-176
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• 1994

As the Tc-99m-MIBI myocardial SPECT demonstrated wide application in the diagnosis of myocardial function, the quantitative and severity-dependent information is currently re quired. In this study, we proposed a computerized method for scoring the fixed defects in terms of extent-weighted severity and for identifying the reversibility in ischemic regions. At the first stage of this method, the transverse slices were reconstructed with 0.4 Nyquist freq. and order 5 Butterworth filter. From the oblique/sagittal slices, maximal count per pixel circumferential profiles were extracted for each sector, and then stress/redist. polar maps were normalized and plotted. For reversibility, the stress polar map was subtracted from the de-layed image and positive-valued pixels were categorized into three grades. The extent-weight-ed severity scores were calculated using the assigned grades and their number of pixels. This procedure was done automatically and the reversibility and severity scores were produced for each of the coronary territories (LAD, RCA, LCX) or any combination of these. Clinical ap-plication has shown that the changes In reversibility scores after PTCA were correlated linearly with the pre PTCA scores(r>0.8) in postinfarct cases as well as in angina, and severity scores of persistent defects in stress/rest SPECT study matched to the regional ejection fraction and visual analysis of regional wall motion of gated blood pool scan(r>0.6). We conclude that the computerized severity scoring method for the analysis of myocardial SPECT could be useful in the assessment of the myocardial ischemia and fixed defect.

• Korean Journal of Head & Neck Oncology
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• v.12 no.2
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• pp.224-229
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• 1996

Head and neck arteriovenous malformation usually forms huge mass, cause profuse bleeding or potenially compromise the airway. This bleeding is vulnerable to be uncontrollable and life­threatening. Sometimes it has a high mortality. Although surgical resection is possible in some cases, the morbidity such as a defects of soft tissue is very high and its reconstruction is very difficult. The authors report an 11 year old female patient in whom occlusion of arteriovenous malformation with glue after transcutaneous embolization made a satisfactory results. At the beginning, she was transferred for massive oral bleeding. The bleeding was persistent and it was not possible to remove the packing in spite of many times of embolizations through feeding arteries. The massive bleeding trom the left upper alveolar mucosa compromised the airway and tracheotomy was done. Whenever the hypovolemic shock was occurred in a short time, blood transfusion and cardiopulmonary resucitation were done. To embolize the vascular mass of arteriovenous malformation, as a final trial before operation, the spinal needle was administered through the left upper gingiva under the fluoroscopy. The glue was injected on the target. The bleeding was stopped and we have noticed the absence of nidus on follow-up angiography after 3 weeks. We experienced that some cases of arteriovenous malformation in head & neck revealing the bleeding could be treated with transcutaneous embolization instead of surgical resection.

• Journal of the Semiconductor & Display Technology
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• v.22 no.1
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• pp.28-32
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• 2023

Recently, the use of stable lithium nanostructures as substrates and electrodes for secondary batteries can be a fundamental alternative to the development of next-generation system semiconductor devices. However, lithium structures pose safety concerns by severely limiting battery life due to the growth of Li dendrites during rapid charge/discharge cycles. Also, enabling long cyclability of high-voltage oxide cathodes is a persistent challenge for all-solid-state batteries, largely because of their poor interfacial stabilities against oxide solid electrolytes. For the development of next-generation system semiconductor devices, solid electrolyte nanostructures, which are used in high-density micro-energy storage devices and avoid the instability of liquid electrolytes, can be promising alternatives for next-generation batteries. Nevertheless, poor lithium ion conductivity and structural defects at room temperature have been pointed out as limitations. In this study, a low-dimensional Graphene Oxide (GO) structure was applied to demonstrate stable operation characteristics based on Li+ ion conductivity and excellent electrochemical performance. The low-dimensional structure of GO-based solid electrolytes can provide an important strategy for stable scalable solid-state power system semiconductor applications at room temperature. The device using uncoated bare NCA delivers a low capacity of 89 mA h g-1, while the cell using GO-coated NCA delivers a high capacity of 158 mA h g−1 and a low polarization. A full Li GO-based device was fabricated to demonstrate the practicality of the modified Li structure using the Li-GO heterointerface. This study promises that the lowdimensional structure of Li-GO can be an effective approach for the stabilization of solid-state power system semiconductor architectures.

• Journal of Korean Foot and Ankle Society
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• v.28 no.1
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• pp.15-20
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• 2024

Purpose: Achilles tendon rupture is a frequently encountered ankle pathology associated with a substantial burden of intense pain and functional deficits. Chronic Achilles tendon ruptures with considerable defects pose intricate repair challenges that are often marred by complications such as re-rupture and persistent pain. Various treatment methods, including allograft transplantation, have been proposed, but the literature on this technique is limited. In this study, we propose a surgical approach utilizing allotendon transplantation and a calcaneal tunneling technique and provide clinical evaluation details. Materials and Methods: Fifteen patients with chronic Achilles tendon ruptures treated with allotendon between 2020 and 2022 were included in the study. Patients were evaluated at 1, 3, and 6 months postoperatively using Visual Analog Scale (VAS) scores and Achilles Tendon Total Rupture Scores (ATRSs). Complications were assessed postoperatively. Results: The average VAS score was 7 before surgery, 7.3 immediately after surgery, and 4.3 at 1 month, 2.5 at 3 months, and 1.3 at 6 months after surgery. Because the sample was limited to 15 individuals and distributions were non-normal, the analysis was conducted using the non-parametric Wilcoxon's signed-rank test, and statistical significance was accepted for p-values<0.05. Results showed a significant improvement in ATRS and VAS scores versus preoperative and immediate postoperative values. VAS scores showed a decreasing trend after surgery, whereas average ATRS scores increased from 14 before surgery, 33.8 at 1 month, 82.7 at 3 months, and 93.9 at 6 months. Conclusion: This study suggests that allograft transplantation using the described calcaneal tunnel technique provides an effective treatment for chronic Achilles tendon ruptures. However, extensive research and long-term clinical trials are required to validate and better understand the technique's efficacy.

• Archives of Plastic Surgery
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• v.50 no.6
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• pp.593-600
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• 2023

Background Soft tissue reconstruction around the knee area is still an open question, particularly in persistent infections and multiple reoperations scenario. Flap coverage should guarantee jointmobility and protection, even when foreign materials are implanted. The chimeric harvesting of the musculocutaneous gastrocnemius flap, based on the sural artery perforators, can extend its applicability in soft tissue reconstruction of the upper leg, overcoming the drawbacks of the alternative pedicled flaps. Methods A multicenter retrospective study was conducted enrolling patients who underwent to a pedicled, chimeric gastrocnemius musculocutaneous-medial sural artery perforator (GM-MSAP) or lateral sural artery perforator (GM-LSAP) flap for knee coverage in total knee arthroplasty (TKA) recurrent infections and oncological or traumatic defects of the upper leg from 2018 to 2021. Outcomes evaluated were the successful soft tissue reconstruction and flap complications. Surgical timing, reconstruction planning, technique, and rehabilitation protocols were discussed. Results Twenty-one patients were included in the study. Nineteen GM-MSAPs and 2 GM-LSAPs were performed (soft tissue reconstruction in infected TKA [12], in infected hardware [4], and in oncological patients [5]). Donor site was closed primarily in 9 cases, whereas a skin graft was required in 12. Flap wound dehiscence (1), distal flap necrosis (1), distal necrosis of the skin paddle (1), and donor site infection (1) were the encountered complications. Flap reraise associated to implant exchange or extensive debridement was successful without requiring any further flap surgery. Conclusion The propeller-perforator GM-MSAP offers qualitative defect coverage and easiness of multiple flap reraise due to skin availability and its laxity.

• Childhood Kidney Diseases
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• v.18 no.1
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• pp.29-35
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• 2014

Introduction: Persistent vesicoureteral reflux (VUR), a major cause of urinary tract infection (UTI) in children, can result in serious renal complications, such as reflux nephropathy and chronic renal failure. We evaluated the clinical characteristics and prognostic factors of VUR. Methods: From December 1993 to May 2011, we examined 117 children with vesicoureteral reflux who were admitted to the Department of Pediatrics and Urology, Chungbuk National University hospital for a UTI. The patients were managed medically or surgically. Results: Male patients had a slightly higher prevalence of VUR than female patients (55%). The degrees of the 161 refluxing ureters, as classified by the International Reflux Study Committee, were as follows: grade I, 15 ureters; grade II, 32 ureters; grade III, 54 ureters; grade IV, 26 ureters; grade V, 34 ureters. One hundred and sixty-one renal units (115 cases) underwent a 99m TC-DMSA renal scan, and 62% showed abnormal findings. The incidence of renal cortical defects showed a direct correlation with the severity of VUR. Ninety-four refluxing ureters were followed up medically, and 66 ureters (67%) either disappeared or improved. However, 9 refluxing ureters persisted. The spontaneous resolution rate of VUR seemed to be higher in younger patients with lower grades of reflux, and without renal cortical defects. Sixty-seven refluxing ureters (41%) were treated surgically, 62 refluxing ureters (92%) disappeared, and 5 refluxing ureters (8%) persisted. Conclusion: The incidence of renal cortical defects in patients with UTIs was 62% (in a 99m TC-DMSA renal scan), and showed a direct correlation with the severity of VUR. The spontaneous resolution rate seemed to be lower in the patients with higher grades of VUR, older age (over 4 years old) and diffuse renal cortical defects.

• Journal of Genetic Medicine
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• v.7 no.1
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• pp.37-44
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• 2010

Purpose : Kabuki syndrome is a multiple congenital malformation syndrome with mental retardation. It was named after its characteristic appearance, a face resembling that of an actor in a Kabuki play. To date, six Korean cases of Kabuki syndrome have ever been reported. Here, we present the phenotypic and genetic characteristics of six patients with Kabuki syndrome. Materials and Methods : Between 2003 and 2009, six Korean girls have been diagnosed and followed up as Kabuki syndrome at Center for Genetic Diseases of Ajou University Hospital. Their clinical and laboratory data were collected and analyzed by the retrospective review of medical records. Results : All six patients showed the characteristic facial dysmorphism and developmental delay. Persistent fingertip pads were also found in all patients. Most patients showed postnatal growth retardation (83.3%) and hypotonia (83.3%). Opthalmologic problems were common, particularly for strabismus (83.3%). Congenital heart defects were present in three patients (50%). Skeletal abnormalities including 5th finger shortening (83.3%), clinodactyly (50%), joint hypermobility (50%) and hip dislocation (16.7%) were also observed. There was no patient who had positive family history for Kabuki syndrome. Cytogenetic and molecular cytogenetic analyses including karyotyping and array CGH could not reveal any underlying genetic cause of Kabuki syndrome. Conclusion : Korean patients with Kabuki syndrome showed a broad spectrum of clinical features affecting multiple organ systems. Although clinical manifestations of Kabuki syndrome have been well established, our results failed to detect recurrent chromosome aberrations which could cause Kabuki syndrome. Its natural history and genetic background remains to be further studied for providing appropriate management and genetic counseling.

• Childhood Kidney Diseases
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• v.5 no.2
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• pp.100-108
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• 2001

Purpose : We investigated the incidence and predisposing factors of pulmonary embolism in minimal change nephrotic syndrome(MCNS). Methods : Lung perfusion scan using 99mTC-MAA were done on 14 patients who were diagnosed to minimal change nephrotic syndrome. Group h: Five patients who had perfusion defects on scan, Group B; Nine patients who had no perfusion defect on scan. Between the two groups, the differences of platelet number, hematocrits, albumin, cholesterol, triglyceride, proteinuria were evaluated. Results : Five patients were found to have perfusion defect consistent with pulmonary embolism($35.7\%$). However, there were minimal or no respiratory symptoms and signs. In our laboratory studies, the mean proteinuria on admissions was $676{\pm}31\;mg/m2/hr$ in the group with pulmonary embolism, and $313{\pm}28\;mg/m2/hr$ in the group without pulmonary embolism. There were more severe proteinuria in group with pulmonary embolism(P<0.05). The mean platelet count at early stage of remission after steroid treatment was $746,600{\pm}280,000/mm3$ in the group with pulmonary embolism, $511,890{\pm}90,000/mm3$ in the group without pulmonary embolism. There were significant difference of platelet count between the two groups(P<0.01). In patients with pulmonary embolism, there were more higher and sustained increasement of platelet count. All cases of pulmonary embolism were treated with dipyridamole(5 mg/kg). In 4 cases the perfusion defects were improved in two weeks, however, one case showed persistent perfusion defect after 1 month. Conclusion : Our study suggested that pulmonry embolism might be one of tile major complications in childhood MCNS The occurrence rate was correlated with severity of proteinuria before treatment and sustained increasement of platelet counts in early remission state after steroid treatment. Therefore, the scintigraphic pulmonary perfusion study is mandatory in childhood MCNS, especially in the high risk patients, such as the patients with severe proteinuria and sustained increasement of platelet count. (J Korean Soc Pediatr Nephrol 2001;5 : 100-8)

• Journal of Chest Surgery
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• v.32 no.6
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• pp.510-517
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• 1999

Background: Total anomalous pulmonary venous connection (TAPVC) is still one of the more challenging congenital heart defects in newborns and young infants. The purpose of the study is to evaluate the early and midterm results of the surgical corrections for patients in early infancy with isolated TAPVC. Material and Method: Hospital records of 15 consecutive patients in early infancy (January 1993 to August 1998) were retrospectively reviewed. There were 8 boys and 7 girls whose ages ranged from 4 days to 3.5 months (median age 22 days). Their body weight ranged from 1.75 kg to 4.9 kg (mean 3.54 kg). The abnormal anatomical connections were supracardiac in 11, cardiac in 3, and infracardiac in 1. In 6 patients (40%), the pulmonary venous drainage was obstructive. Total circulatory arrest was used in 13 patients. Anastomosis between the common pulmonary vein and the left atrium was performed with a continuous suture technique using a fine nonabsorbable polypropylene suture through a lateral approach behind the right atrium. Result: There was one hospital death (6.5%) caused by a sepsis 17 days after the operation in a neonate who had supracardiac drainage and was dependent on a ventilator preoperatively. There were 2 late deaths. One died sudde`nly of an unknown cause at home 2.5 years after the operation and the other died of a recurrent pulmonary hypertension 3 months after the reoperation due to pulmonary venous obstruction (PVO). Two patients required reoperations because of PVO 5 months and 10 months respectively after the initial operation. Of these patients, one patient is alive at the present time with persistent pulmonary hypertension. All survivors without postoperative PVO (78.6%) were in NYHA functional class I at mean follow-up of 25.8 months (0.5∼67 months). Conclusion: Surgical correction of TAPVC in early infancy can be performed at low risk. However, there were 2 postoperative PVOs (14.3%) which had bad results. The survivors without postoperative PVO had excellent functional status.