소프트웨어요구 분석 지원 도구 ( START ) 의 개발에 관한 연구 ( A Study on Development of START ( Structured Analyzing & Reporting Tool ) )

채동식,김종현,오해영,조영화,김봉일 대한전자공학회 1989 특정연구 결과 발표회 논문집 Vol.- No.-

양측 대퇴골 전자하 내측에 발생한 부전 골절: 증례 보고

채동식 ( Dong Sik Chae ),이정한 ( Jung Han Lee ),이우석 ( Woo Suk Lee ),양익환 ( Ick Hwan Yang ),한창동 ( Chang Dong Han ) 대한고관절학회 2013 Hip and Pelvis Vol.25 No.3

외상력없이 발생한 불완전 부전 골절은 흔히 대퇴골 피질부의 외측에서 발견되는 반면 불완전 피로 골절은 내측에서 관찰되는데, 저자들은 외상력이나 약물 복용의 과거력없이 발생한 두 달간의 양측 대퇴부 내측부 통증으로 내원한 66세 여환으로 대퇴골 피질부의 내측을 침범하는 양측 전자하 부전 골절을 보고하는 바이다. A non-traumatic, incomplete insufficiency fracture commonly involves the lateral side of the femoral cortex; whereas a non-traumatic, incomplete stress fracture commonly involves the medial side of the femoral cortex. Here, we describe a case of a 66-year-old woman with a two-month history of bilateral thigh pain without trauma or medication usage who was diagnosed with bilateral subtrochanteric insufficiency fractures involving the medial side of the femoral cortex.

소프트웨어요구 분석 지원 도구 ( START ) 의 개발에 관한 연구 ( A Study on Development of START ( Structured Analyzing & Reporting Tool )

조영화,채동식,김종현,오해영,김봉일 한국통신학회 1989 한국통신학회 학술대회논문집 Vol.1 No.2

A Simplified Phenomenological Theory of Viscosity for Liquid Metals

김원수,채동식,Kim, Won Su,Chae, Dong Sik Korean Chemical Society 2001 Bulletin of the Korean Chemical Society Vol.22 No.1

This study simplifies the phenomenological theory of viscosity previously proposed by the present authors. This simplified theory has only two thermodynamic properties and one parameter, as opposed to its predecessor, which has many, allowing for easy calculation of the liquid viscosities. The viscosity of liquid metals, an excellent test for checking the validity of the liquid theory, can be calculated using the equation based on the simplified theory. The calculated results by the current theory turn out to be good for the liquid metals, including sodium, potassium, rubbidium, cesium, lead and mercury.

Decreased Lumbar Lordosis and Deficient Acetabular Coverage Are Risk Factors for Subchondral Insufficiency Fracture

조우람,이우석,채동식,양익환,이경민,구경회 대한의학회 2016 Journal of Korean medical science Vol.31 No.10

Subchondral insufficiency fracture (SIF) of the femoral head occurs in the elderly and recipients of organ transplantation. Osteoporosis and deficient lateral coverage of the acetabulum are known risk factors for SIF. There has been no study about relation between spinopelvic alignment and anterior acetabular coverage with SIF. We therefore asked whether a decrease of lumbar lordosis and a deficiency in the anterior acetabular coverage are risk factors. We investigated 37 patients with SIF. There were 33 women and 4 men, and their mean age was 71.5 years (59-85 years). These 37 patients were matched with 37 controls for gender, age, height, weight, body mass index and bone mineral density. We compared the lumbar lordosis, pelvic incidence, pelvic tilt, sacral slope, acetabular index, acetabular roof angle, acetabular head index, anterior center-edge angle and lateral center-edge angle. Lumbar lordosis, pelvic tilt, sacral slope, lateral center edge angle, anterior center edge angle, acetabular index and acetabular head index were significantly different between SIF group and control group. Lumbar lordosis (OR=1.11), lateral center edge angle (OR=1.30) and anterior center edge angle (OR=1.27) had significant associations in multivariate analysis. Decreased lumbar lordosis and deficient anterior coverage of the acetabulum are risk factors for SIF as well as decreased lateral coverage of the acetabulum.

머신러닝 기반 무릎 골 관절염 심각도 분류를 위한 특징 중요도 분석

신영철,김성우,채동식,유선국 대한전자공학회 2020 전자공학회논문지 Vol.57 No.2

In this study, the OsteoArthritis Initiative(OAI) dataset was used to evaluate four statistical methods to determine the importance of 6 clinical information and 18 X-ray image features for knee osteoarthritis severity classification. The Kellgren-Lawrence Grade, knee osteoarthritis seveirity classification scoring system was classified using a random forest method which used features of high importance. Joint space narrowing, osteophytes, and osteoosclerosis were ranked in the top five most important features in all methods. The model using 24 features had a balanced classification accuracy of 93.7%, while the model using 12 features including clinical information, joint space narrowing, and osteophytes, had a balanced classification accuracy of 93.4%. Both models had similar levels of accuracy, but calculation cost to obtain image features of the second model was lower than the first model. It used one-thirds of features of the first model and required the use of only 6 image features compared to the first methods required use of 18 image features. 이 논문에서는 골관절염 이니셔티브 (The OsteoArthritis Initiative, OAI) 데이터 셋을 사용하여 4가지 통계학적 방법으로 무릎 골 관절염 심각도 분류와 관계된 6가지의 임상정보와 18가지 X-ray영상 특징들의 중요성을 평가하였다. 또한, 중요도가 높게 평가된 특징들을 활용하여 무릎 골 관절염 심각도 분류 점수체계인 Kellgren-Lawrence Grade(K-L Grade)를 머신러닝 방법 중 하나인 Random Forest로 분류하였다. 특징 중요도 평가 결과로는, 관절간격감소(Joint Space Narrowing, JSN), 골극(Osteophytes, OS), 골 경화증(Osteosclerosis, SC)이 모든 특징 중요도 평가 방법에서 상위 5위를 이상을 차지하였다. 심각도 분류 결과로는, 24가지 전체 특징을 사용한 모델의 분류 정확도가 93.7%, 임상 정보, JSN 및 OS를 포함하는 12가지 특징을 활용한 모델의 정확도는 93.4%로 나타났다. 영상학적 특징들을 18개에서 1/3인 6개로 감소시킨 두 번째 모델은, 영상학적 특징을 얻기 위한 계산 비용은 더 적지만, 정확도는 전체 특징을 활용한 모델의 정확도와 유사하였다.

견관절 관절경 수술시 관류액 내에 발생하는 이물질

이진웅,허윤무,채동식,오형탁 대한견주관절의학회 2011 대한견주관절학회 학술대회논문집 Vol.2011 No.3

Effect of Zoledronate on the Expression of Vascular Endothelial Growth Factor-A by Articular Chondrocytes and Synovial Cells: An in Vitro Study

이진웅,이우석,김상범,허윤무,채동식 대한골대사학회 2014 대한골대사학회지 Vol.21 No.4

Background: The aim of this in vitro study was to determine the effect of zoledronate,which is frequently used to treat osteoporosis, on osteoarthritis by analyzing zoledro-nate-induced expression of vascular endothelial growth factor-A (VEGF-A) in chondro-cytes and synovial cells. Methods: After chondrocytes and synovial cells were separatedand cultured, zoledronate was added, and VEGF-A and pigment epithelium-derived fac-tor (PEDF) expression were quantified by real-time polymerase chain reaction and West-ern blotting. Results: There was no significant difference in the expression of VEGF-AmRNA in chondrocytes between the zoledronate group and the control group on the8th day of culture. The expression of both VEGF-A and PEDF mRNA in synovial cells wassignificantly decreased in the zoledronate group (P<0.05). Conclusions: Zoledronatedecreases the expression of VEGF-A in synovial cells and may affect the developmentand progression of osteoarthritis.

Diagnosis and Treatment of Inflammatory Joint Disease

김이석,오현철,박장원,김인성,김준영,김기철,채동식,조우람,송주현 대한고관절학회 2017 Hip and Pelvis Vol.29 No.4

Arthritis damages the cartilage within joints, resulting in degenerative changes, including loss of function and joint instability. Ankylosing spondylitis (AS) is a chronic inflammatory condition affecting the spine and boneto-tendon attachment area within the sacroiliac joint leading to back pain and progressive spinal stiffness. In the final stages, AS causes hyperkyphosis-a condition closely tied to the human leukocyte antigen-B27 gene. Rheumatoid arthritis is a chronic, systemic autoimmune disease characterized by the simultaneous inflammation of the synovium of multiple joints, leading to joint damage (e.g., destruction, deformation and disability). In the past, nonsteroidal anti-inflammatory drugs or conventional disease-modifying antirheumatic drug (DMARDs) have been used for the treatment of these autoimmune diseases, but biologic DMARDs have recently been introduced with excellent results. Gout is a chronic inflammatory disease that causes an alteration of joints resulting in severe pain. Specifically, gout is associated with an accumulation of uric acid within the body resulting from dysregulated purine metabolism, causing recurrent paroxysmal inflammation in the joints. Allopurinol and febuxostat are the primary treatment options for individuals with gout. It is necessary to have an accurate understanding of the pathogenesis, pathological ecology and treatment of AS, rheumatoid arthritis, and gouty arthritis, which are the representative diseases that may cause inflammatory arthritis.

반월연골판의 퇴행성 변화 정도에 대한 자기 공명 영상과 조직학적 및 생화학적 소견의 비교

정환용(Whan Yong Chung),성승용(Seung Yong Sung),채동식(Dong-Sik Chae) 대한정형외과학회 2015 대한정형외과학회지 Vol.50 No.1

목적: 자기 공명 영상에서 반월연골판의 퇴행성 변화 정도가 조직학적 및 생화학적 변화와 상관 관계가 있는지 알아보고자 하였다. 대상 및 방법: 슬관절 전치환 수술 환자와 사체의 반월연골판을 대상으로, 자기 공명 영상을 이용하여 반월연골판의 퇴행성 정도를 평가하고 조직학적 및 생화학적 변화 정도를 확인하고 두 군을 비교하였다. 결과: 대조군의 반월연골판은 자기 공명 영상 및 조직학적 소견상 0단계로 확인되었으며 생화학적 검사상 대상들 간의 차이가 없었다. 실험군의 반원연골판은 자기 공명 영상에서 퇴행성 변화가 증가할수록 수분과 단백 다당이 증가하였고, 반면에 교원질은 감소하였다. 모든 군에서 자기 공명 영상에서 0단계를 보이는 반원연골판의 조직학적 소견은 유사하게 관찰되었으나 생화학적 특성은 차이가 있었다. 자기 공명 영상상 I, II단계의 퇴행성 변화는 조직학적 소견과 일치하지 않았다. 결론: 자기 공명 영상에서 관찰되는 반월연골판의 퇴행성 변화의 정도는 조직학적 소견과 일치하지 않았다. 이는 수분의 양 때문으로 생각되며 자기 공명 영상상 퇴행성 외측 반월연골판의 고강도 신호의 원인으로는 교원질의 감소와 단백당의 증가로 예상된다. 그래서 자기 공명 영상에서 관찰되는 퇴행성 반월연골판으로 조직학적 퇴행 정도를 판단할 때에는 주의를 요한다. Purpose: The aim of this study is to determine whether degeneration severities of meniscus assessed using magnetic resonance imaging (MRI) would well estimate those assessed using histological and biochemical examinations. Materials and Methods: Seven lateral menisci from knees with osteoarthritis undergoing total knee arthroplasty (study group) and five from normal controls (control group) were examined for this study. Degeneration severities of the menisci were graded using MRI, histologic and biochemical examinations of the menisci were then performed. Comparative analyses of MRI grading and results of histological/biochemical examinations of the menisci were performed in each group. In addition, comparative analyses of histological/biochemical conditions were performed between specimens of the study group and the control group showing grade 0 on MRI. Results: All specimens from the control group showed grade 0 on MRI and their histology was also grade 0. In addition, no significant differences in biochemical results were observed among the specimens of the control group. In the lateral meniscus from the study group showing degeneration on MRI it was found that the water and proteoglycan contents increased with increasing grade of degeneration whereas the collagen content decreased. The meniscus specimens of the control group and the study group showing grade 0 on MRI had similar histologic findings but had different biochemical properties. The grade I, II degenerations on MRI were not well matched with the histologic findings in the study group. Conclusion: Severities of meniscus degeneration on MRI did not well reflect the histologic findings of the meniscus. This finding may be due to the water content of the meniscus. The factors of the high signal intensity of the degenerated lateral meniscus on MRI may be due to the decreased component of collagen and increased proteoglycan. Our findings suggested that caution should be taken when the severities of meniscus degeneration on MRI are attributed to histologic severities of degenerated meniscus.