1.Influence of Parent Artery Segmentation and Boundary Conditions on Hemodynamic Characteristics of Intracranial Aneurysms.
Yufeng HUA ; Je Hoon OH ; Yong Bae KIM
Yonsei Medical Journal 2015;56(5):1328-1337
PURPOSE: The purpose of this study is to explore the influence of segmentation of the upstream and downstream parent artery and hemodynamic boundary conditions (BCs) on the evaluated hemodynamic factors for the computational fluid dynamics (CFD) analysis of intracranial aneurysms. MATERIALS AND METHODS: Three dimensional patient-specific aneurysm models were analyzed by applying various combinations of inlet and outlet BCs. Hemodynamic factors such as velocity pattern, streamline, wall shear stress, and oscillatory shear index at the systolic time were visualized and compared among the different cases. RESULTS: Hemodynamic factors were significantly affected by the inlet BCs while there was little influence of the outlet BCs. When the inlet length was relatively short, different inlet BCs showed different hemodynamic factors and the calculated hemodynamic factors were also dependent on the inlet length. However, when the inlet length (L) was long enough (L>20D, where D is the diameter of inlet section), the hemodynamic factors became similar regardless of the inlet BCs and lengths. The error due to different inlet BCs was negligible. The effect of the outlet length on the hemodynamic factors was similar to that of the inlet length. CONCLUSION: Simulated hemodynamic factors are highly sensitive to inlet BCs and upstream parent artery segmentation. The results of this work can provide an insight into how to build models and to apply BCs for more accurate estimation of hemodynamic factors from CFD simulations of intracranial aneurysms.
Adult
;
Arteries
;
Blood Flow Velocity
;
*Hemodynamics
;
Humans
;
Hydrodynamics
;
Intracranial Aneurysm/*physiopathology
;
*Models, Cardiovascular
;
Stress, Mechanical
2.Analysis of Pulmonary Asbestos Body in Malignant Mesothelioma: A case report.
Hoon Kyu OH ; Jae Yoe RO ; Chul Jong YOON ; Je Geun CHI
Korean Journal of Pathology 1999;33(5):361-366
The association between occupational asbestos exposure and the subsequent development of malignant mesothelioma of pleura is well recognized. We analyzed an asbestos body by energy dispersive X-ray analyser in a case of malignant mesothelioma of pleura who had a history of asbestos exposure 30 years ago. In transmission electron microscope, the asbestos body was composed of a core of refractile thin asbestos fiber bundle and beaded masses of electron-dense iron and protein complex. The core fibers were analyzed as an amphibole type crocidolite fiber [(Na2Fe3Fe2(Si8O22)(OH)2] which composed of high content of silicon, iron and sodium.
Asbestos*
;
Asbestos, Crocidolite
;
Iron
;
Mesothelioma*
;
Pleura
;
Silicon
;
Sodium
3.Tarsometatarsal Fracture: Dislocation
Hyung Ku YOON ; Kuk Hwan OH ; Kyung Hoon KANG ; Jin Il KIM ; Man Je PARK
The Journal of the Korean Orthopaedic Association 1995;30(3):765-770
Tarsometatarsal injury has not been paid much attention due to it is unusual frequency. But the cases of tarsometatarsal injuries are on the increase in proportion to the increasing "high energy trauma injury" resulted from the traffic and industrial accidents. The purpose of this study is both assessing the relative effects among clinical results, final radiologic findings, treatment results and symtoms. In view of the results so far achieved from 20 cases of tarsometatarsal fracture dislocation which had been treated at Sung-Ae general hospital from January 1990 to December 1993, the results were as follows: 1. Thirteen cases were treated by open reduction and 3 cases were treated by closed reduction with smooth pins but no reduction loss were experienced. 2. Traumatic arthrosis could be observed in 14 cases but there were no influences on the functional end results. 3. Anatomical results correlated with pain. 4. Anatomical or neraly anatomical reduction was considered as most important factor of prognosis.
Accidents, Occupational
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Dislocations
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Hospitals, General
;
Prognosis
5.A Case of Macrogynecomastia Treated by Reduction Mammoplasty.
Hyeong Doo CHO ; Je Woo KIM ; Young Ah LEE ; Hae Sun YOON ; Jeh Hoon SHIN ; Phil Soo OH
Journal of Korean Society of Pediatric Endocrinology 1998;3(2):237-241
Gynecomastia is a proliferation of the glandular component of the male breast. Gynecomastia is the most common variant condition of the male breast and results from the effect of an altered estrogen-androgen balance on breast tissue or from the increased sensitivity of breast tissue to a normal estrogen level. We experienced a case of macrogynecomastia in a 16-year-old boy who had a normal male phenotype and was treated by reduction mammoplasty with breast tissue removal, which was effective and produced good cosmetic and psychologic results.
Adolescent
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Breast
;
Estrogens
;
Female
;
Gynecomastia
;
Humans
;
Male
;
Mammaplasty*
;
Phenotype
6.Peer-assisted learning to train high-school students to perform basic life-support
Soo-Hyung CHOI ; Hoon-Dong LEE ; Woong-Chan KIM ; Eun-Sung KIM ; Hyeok-Je OH
World Journal of Emergency Medicine 2015;6(3):186-190
BACKGROUND: The inclusion of cardiopulmonary resuscitation (CPR) in formal education has been a useful approach to providing basic life support (BLS) services. However, because not all students have been able to learn directly from certified instructors, we studied the educational efficacy of the use of peer-assisted learning (PAL) to train high-school students to perform BLS services. METHODS: This study consisted of 187 high-school students: 68 participants served as a control group and received a 1-hour BLS training from a school nurse, and 119 were included in a PAL group and received a 1-hour CPR training from a PAL leader. Participants' BLS training was preceded by the completion of questionnaires regarding their background. Three months after the training, the participants were asked to respond to questionnaires about their willingness to perform CPR on bystander CPR and their retention of knowledge of BLS. RESULTS: We found no statistically significant difference between the control and PAL groups in their willingness to perform CPR on bystanders (control: 55.2%, PAL: 64.7%,P=0.202). The PAL group was not significantly different from the control group (control: 60.78±39.77, PAL: 61.76±17.80, P=0.848) in retention of knowledge about BLS services. CONCLUSION: In educating high school students about BLS, there was no significant difference between PAL and traditional education in increasing the willingness to provide CPR to bystanders or the ability to retain knowledge about BLS.
9.A Case of Hypocortisolemia Presented by Short Stature.
Mi Yeon CHOI ; Seon Hee SHIN ; Jeh Hoon SHIN ; Je Woo KIM ; Young Ah LEE ; Ha Joo CHOI ; Hae Sun YOON ; Phil Soo OH
Journal of Korean Society of Pediatric Endocrinology 1998;3(1):79-83
Isolated ACTH deficiency is a rare cause of secondary adrenocortical insufficiency. The clinical presentation can be similar to that of primary adrenal insufficiency, but most of them may be nonspecific. A female patient of 25 months of age, complainig short stature, showed hypocortisolemia without ACTH & cortisol stimulation by insulin-induced hypoglycemia test. All the other hormone state was normal. Left hand AP view revealed delayed bone age(3 month) compared with chronological age. No radiologic abnormality was found in sella MRI and adrenal CT. Here we report a case of isolated ACTH deficiency presented by short stature.
Addison Disease
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Adrenocorticotropic Hormone
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Female
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Hand
;
Humans
;
Hydrocortisone
;
Hypoglycemia
;
Magnetic Resonance Imaging
10.Anterior Shoulder Instability with Concomitant Superior Labrum from Anterior to Posterior (SLAP) Lesion Compared to Anterior Instability without SLAP Lesion.
Claire Marie C DURBAN ; Je Kyun KIM ; Sae Hoon KIM ; Joo Han OH
Clinics in Orthopedic Surgery 2016;8(2):168-174
BACKGROUND: The aims of this study were to investigate the clinical characteristics of patients with combined anterior instability and superior labrum from anterior to posterior (SLAP) lesions, and to analyze the effect of concomitant SLAP repair on surgical outcomes. METHODS: We retrospectively reviewed patients who underwent arthroscopic stabilization for anterior shoulder instability between January 2004 and March 2013. A total of 120 patients were available for at least 1-year follow-up. Forty-four patients with reparable concomitant detached SLAP lesions (group I) underwent combined SLAP and anterior stabilization, and 76 patients without SLAP lesions (group II) underwent anterior stabilization alone. Patient characteristics, preoperative and postoperative pain scores, Rowe scores, and shoulder ranges of motion were compared between the 2 groups. RESULTS: Patients in group I had higher incidences of high-energy trauma (p = 0.03), worse preoperative pain visual analogue scale (VAS) (p = 0.02), and Rowe scores (p = 0.04). The postoperative pain VAS and Rowe scores improved equally in both groups without significant differences. Limitation in postoperative range of motion was similar between the groups (all p-value > 0.05). CONCLUSIONS: Anterior instability with SLAP lesion may not be related to frequent episodes of dislocation but rather to a high-energy trauma. SLAP fixation with anterior stabilization procedures did not lead to poor functional outcomes if appropriate surgical techniques were followed.
Dislocations
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Follow-Up Studies
;
Humans
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Incidence
;
Pain, Postoperative
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Range of Motion, Articular
;
Retrospective Studies
;
Shoulder Dislocation
;
Shoulder*