2.Graf Soft Fixation for the Treatment of Degenerative Lumbar Disease.
Yoon HA ; Young Soo KIM ; Do Heum YOON ; Dong Kyu JIN ; Hei Wan PARK
Journal of Korean Neurosurgical Society 1998;27(10):1370-1378
Degenerative involution of the spine causes destruction of spinal stabilizer which consists of bone, ligament, joint capsule, and disc, which substantially leads to hypermobility and instability of the spine. Generally the hard fixation system has been used for the treatment of lumbar instability. However, it has many complications, including screw loosening, screw fracture, and instability on, above, and below the fusion segment. These complications of the hard fixation system has brought to the invention of a more physiologic fixation device, the soft fixation system. We have used the Graf soft fixation system as an instrument for degenerative lumbar disease. 106 cases were operated between August, 1993 and March, 1996. The clinical assessments, radiologic findings, and operative results were analyzed. The height of disc space significantly increased from 8.84mm to 9.84mm on L3/4, 9.28mm to 10.13mm on L4/5, and 9.44mm to 10.47mm on L5/S1. Flexion instability changed from -6.9 degrees to 5.5degrees on L3/4, -7.45 degrees to 5.04 degrees on L4/5, -2.09degrees to 10.81degrees on L5/S1, translation instability was corrected from 16.8% to 14.9% on L3/4, 19.9% to 12.4% on L4/5, 27.1% to 20.1% on L5/S1 after Graf soft fixation. The clinical results were as follows: excellent in 56%, 27% good, 9% fair, and 8% poor. These results suggest that Graf soft fixation system for degenerative lumbar disease would not only be useful and effective, but also be safer in terms of unwanted complications of the hard fixation system.
Inventions
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Joint Capsule
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Ligaments
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Spine
4.The Accuracy of measurements during model surgery for orthognathic planning.
Sang Hwy LEE ; Seung Hoon LEE ; Hyeon Ho JU ; Dong Hwan WON
Journal of the Korean Association of Oral and Maxillofacial Surgeons 2001;27(1):37-45
The errors in orthognathic surgery can occur during the preoperative preparations including the model surgery, but till now there's been some lack of reserches about them. So we wanted to verify the accuracies in measurements used in model surgery. We compared the accuracy of measurements by vernier calipers, which has been the main measurement tool for conventional model surgery, and that by height gauge, which is recently claimed to be more accurate, with 3 dimensional coordinate analyzer. We could have following results and have a plan to use them for the invention of new model surgery techniques. 1. The measurement errors in Group 1, which mean the difference between "the measurements by 3-D analyzer" and "the measurements by height gauge", were small enough with the range of 0.1~0.2mm in all planes. 2. The mean error in Group 2, which is the differences between the measurements of 3-D analyzer and those of vernier calipers, was 1.1mm. 3. The measurement errors in Group 2 were variable according to the factors including the differences of individuality and expertness of each measurers. But in case of Group 1, they were small and not variable by the expertness. 4. The measurements were more accurate at the points in anterior teeth than in molar teeth in Group 1 and 2. 5. The errors after model surgery increased remarkably, compared with those before surgery in Group 2. And the situation was different in Group 1 in that errors decreased after surgery. Accoding to these results, it assumed that the measurements with height gauge during the model surgery for orthognathic surgery are accurate enough and can be maintained, regardless of complexity of models, individuality, or expertness of measurers.
Individuality
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Inventions
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Molar
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Orthognathic Surgery
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Tooth
5.Analysis of Compression Behavior on Intervertebral Disc L4-5 in Pedicle Screw System Instrumented Lumbar Spine under Follower Load.
Myun whan AHN ; Jong chul AHN ; Su ho LEE ; Il sub CHUNG ; Choon yeol LEE ; Jang woo LEE
Yeungnam University Journal of Medicine 2003;20(2):160-168
BACKGROUND: Confirm the stability of intervertebral disc sustaining each fused lumbar spine cases, comparing vertical compression, A-P shear force and rotational moment on intervertebral disc of instrumented lumbar spine with simple vertical compression load and follower load using finite element analysis. MATERIALS AND METHODS: We analyze the stability of intervertebral disc L4-5 supporting fused lumbar spine segments. After performing finite element modelling about L1-L5 lumbar vertebral column and L1-L4 each fusion level pedicle screw system for fused lumbar spine fine element model. Intervertebral discs with complex structure and mechanical properties was modeled using spring element that compensate stiffness and tube-to-tube contact element was employed to give follower load. Performing geometrical non-linear analysis. RESULTS: The differences of intervertebral disc L4-5 behavior under the follower compression load in comparision with vertical compression load are as follows. CONCLUSION: As a result of finite element interpretation of instrumented lumbar spine, the stability of L4-5 sustaining fused lumbar segment, the long level fused lumbar spine observed hing stability under follower load. This research method can be the basis tool of effects prediction for instrumentation, a invention of a more precious finite element interpretation model which consider the role of muscle around the spine is loaded.
Finite Element Analysis
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Intervertebral Disc*
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Inventions
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Spine*
6.Analysis of Compression Behavior on Intervertebral Disc L4-5 in Pedicle Screw System Instrumented Lumbar Spine under Follower Load.
Myun whan AHN ; Jong chul AHN ; Su ho LEE ; Il sub CHUNG ; Choon yeol LEE ; Jang woo LEE
Yeungnam University Journal of Medicine 2003;20(2):160-168
BACKGROUND: Confirm the stability of intervertebral disc sustaining each fused lumbar spine cases, comparing vertical compression, A-P shear force and rotational moment on intervertebral disc of instrumented lumbar spine with simple vertical compression load and follower load using finite element analysis. MATERIALS AND METHODS: We analyze the stability of intervertebral disc L4-5 supporting fused lumbar spine segments. After performing finite element modelling about L1-L5 lumbar vertebral column and L1-L4 each fusion level pedicle screw system for fused lumbar spine fine element model. Intervertebral discs with complex structure and mechanical properties was modeled using spring element that compensate stiffness and tube-to-tube contact element was employed to give follower load. Performing geometrical non-linear analysis. RESULTS: The differences of intervertebral disc L4-5 behavior under the follower compression load in comparision with vertical compression load are as follows. CONCLUSION: As a result of finite element interpretation of instrumented lumbar spine, the stability of L4-5 sustaining fused lumbar segment, the long level fused lumbar spine observed hing stability under follower load. This research method can be the basis tool of effects prediction for instrumentation, a invention of a more precious finite element interpretation model which consider the role of muscle around the spine is loaded.
Finite Element Analysis
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Intervertebral Disc*
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Inventions
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Spine*
7.A Decade of Scientific and Technological Innovation at Chinese Academy of Medical Sciences & Peking Union Medical College: Retrospect and Prospect.
Tao-Lian YANG ; Hua ZHONG ; Wei WANG ; Jian-Wei WANG
Chinese Medical Sciences Journal 2022;37(3):240-245
Focusing on the reform initiatives of Chinese Academy of Medical Sciences (CAMS) & Peking Union Medical College (PUMC) in medical scientific and technological innovation from perspectives of deepening the reform and optimizing the ecosystem of science and technology innovation, this article summarizes the highlights of CAMS & PUMC's efforts in safeguarding people's health and promoting the Healthy China 2030 strategy through scientific and technological innovation in the fields including basic research, disease prevention and treatment, and medical technology in the past ten years. These achievements embody the endeavors and responsibility of CAMS & PUMC in realizing self-reliance and self-improvement of Chinese medical science and technology and highlight its contributions to the development of medical science and technology of China.
Humans
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Inventions
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Ecosystem
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Academies and Institutes
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China
8.“VisionTouch Phone” for the Blind
Malaysian Journal of Medical Sciences 2013;20(5):1-4
Our objective is to enable the blind to use smartphones with touchscreens to make calls and to send text messages (sms) with ease, speed, and accuracy. We believe that with our proposed platform, which enables the blind to locate the position of the keypads, new games and education, and safety applications will be increasingly developed for the blind. This innovative idea can also be implemented on tablets for the blind, allowing them to use information websites such as Wikipedia and newspaper portals.
Visually Impaired Persons
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Cell Phones
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Inventions
9.Transillumination of Maxillary Sinuses: A Clinical Re-evaluation.
Jeung Gweon LEE ; Kyung Shik SUH ; Kyung Su KIM ; Sung Yoon AHN ; Seung Soo LEE ; Joon Hyup LEE ; Won Sok KIM ; Dong Young KIM
Korean Journal of Otolaryngology - Head and Neck Surgery 1997;40(7):1020-1025
BACKGROUND: Transillumination of maxillary sinuses was an important method before the invention of X-rays. But as the more precise and valuable methods have been developed, its importance has been reduced in clinical practice. OBJECTIVES: To elucidate the vailidity of the transillumination in diagnosing the maxillary sinus diseases, the transillumination method was compared with the conventional PNS series. MATERIALS AND METHOD: We performed transillumination tests in 100 adults(48 males and 52 females). A fiberoptic cable with halogen light sorce was enough for the examination. The light detected in the face of examinee in the dark room was evaluated. We studied the clinical reliability of transillumination in representing the status of the maxillary sinus. RESULTS: For bilateral sinusitis group(N=48), transillumination matched with the conventinal PNS series in 64.6%(31/48) of the cases, unilateral sinusitis group(N=17) in 82.4%(14/17) and normal group(N=35) in 88.6%(30/35). The overall matched-rate was 75%(75/100). CONCLUSIONS: The transillumination is a helpful non-invasive mothod for clinical evaluation of the maxillary sinus conditions.
Humans
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Inventions
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Male
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Maxillary Sinus*
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Sinusitis
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Transillumination*
10.Discussion on Administrative Innovation of Medical Device in China and U.S.
Yue MIN ; Wengchi LAN ; Bin LIU
Chinese Journal of Medical Instrumentation 2018;42(3):206-209
This article refreshes the innovative review approach of medical device in China at first. It proposes reference through presenting a series of existing review and approval of innovative medical device in U.S. as well as new tools and methods for supporting scientific review.
China
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Device Approval
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Equipment and Supplies
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Inventions