반복적 양측 운동학습에 따른 대뇌 및 소뇌 피질 활성화

태기식,송성재,김영호,Tae, Ki-Sik,Song, Sung-Jae,Kim, Young-Ho 대한의용생체공학회 2007 의공학회지 Vol.28 No.1

The aim of this study was to evaluate effects of short-tenn repetitive-bilateral excercise on the activation of motor network using functional magnetic resonance imaging (fMRI). The training program was performed at 1 hr/day, 5 days/week during 6 weeks. Fugl-Meyer Assessments (FMA) were performed every two weeks during the training. We compared cerebral and cerebellar cortical activations in two different tasks before and after the training program: (1) the only unaffected hand movement (Task 1); and (2) passive movements of affected hand by the active movement of unaffected hand (Task 2). fMRI was performed at 3T with wrist flexion-extension movement at 1 Hz during the motor tasks. All patients showed significant improvements of FMA scores in their paretic limbs after training. fMRI studies in Task 1 showed that cortical activations decreased in ipsilateral sensorimotor cortex but increased in contralateral sensorimotor cortex and ipsilateral cerebellum. Task 2 showed cortical reorganizations in bilateral sensorimotor cortex, premotor area, supplemetary motor area and cerebellum. Therefore, this study demonstrated that plastic changes of motor network occurred as a neural basis of the improvement subsequent to repetitive-bilateral excercise using the symmetrical upper-limb ann motion trainer.

뇌손상 후 운동신경기능 회복에 대한 대칭형 상지 운동기구의 효과: 기능적 뇌 자기공명영상 연구

태기식,최희석,송성재,김영호,Tae Ki-Sik,Choi Hue-Seok,Song Sung-Jae,Kim Young-Ho 한국의학물리학회 2005 의학물리 Vol.16 No.1

본 연구에서는 건측 손의 운동에 따라 환측 손이 대칭적으로 운동하며 두 가지 운동이 가능한 대칭형 상지 운동기구를 개발하고 개발된 대칭형 상지운동 기구를 이용한 6주간의 훈련 후 상지운동 기능 평가인 Fugl-Meyer 검사를 실시하고 기능적 자기공명영상(fMRI)을 통한 뇌 활성화의 변화를 관찰하였다. 편마비 환자를 위하여 건측 손의 운동을 환측 손으로 전달하여 손목의 굴곡과 신전, 전완의 회내와 회외 운동을 유도하는 대칭형 상지 운동기구를 제작하고 제작한 기구의 운동효과를 검증하기 위하여 대뇌병변이나 정신분열증 경험이 없는 오른손잡이인 성인 3명을 대조군으로 선정하고 편마비 발생 후 2년 이상 경과하여 손상된 상지의 자발적 회복과정이 끝났고 제시된 과제 수행이 가능한 만성 편마비 환자 남성 3명을 환자군으로 선정하였다. 제작된 대칭형 상지 운동기구를 이용한 총 6주간의 훈련 후 측정된 Fugl-Meyer 검사에서 훈련에 참가한 모든 편마비 환자들의 상지 운동기능이 현저하게 향상되었다. 또한 만성 편마비 환자를 대상으로 하여 제작된 기구를 적용하여 뇌 활성화를 관찰하기 위해 영상 촬영을 진행하는 동안 모든 피검자들에게 대조군에게는 우세 손을 환자군에게는 건측 손만 손잡이를 잡고 손목의 굴곡/신전 운동(과제 1)을 하고, 양손 모두 손잡이를 잡은 채로 건측 손만을 움직여서 환측 손이 수동적으로 대칭 운동(과제 2)을 하는 두 가지 과제를 수행하게 하였다. 과제 1에서는 운동 전에 비해 대측 SMC의 활성 강도가 증가되고 동측 SMC는 감소하였다. 과제 2에서는 환자에 따라 운동 전에 다양한 영역에서 활성화되다가 운동 후 양측 SMC 및 SMA, PMA 영역 등의 이차 운동영역의 재조직화가 관찰하여 각 과제에 대한 운동 전후의 대뇌 피질의 재조직화가 손의 운동성 회복과 관련이 있음을 확인하였다. 본 연구를 통해 만성편마비 환자에게 본 기구를 적용시켰을 때 물리 치료적 중재로 인한 운동기능 회복 향상과 손 운동에 대한 기능적 자기공명 영상을 비교함으로써 대뇌 피질의 재조직화를 관찰할 수 있었다. The effect of the developed symmetric upper extremity motion trainer on the cortical activation pattern was investigated in three chronic hemiparetic patients using both fMRI and Fugl-Meyer test. The training program was performed at 1 hr/day, 5 days/week during 6 weeks. Fugl-Meyer tests were performed every two weeks during the training. fMRI was performed at 3T scanner with wrist flexion-extension in two different tasks before and after the training program: the only unaffected hand movement (Task 1) and passive movements of affected hand by the active movement of unaffected hand (Task 2). fMRI studies in Task 1 showed that cortical activations decreased in ipsilateral SMC but increased in contralateral SMC. Task 2 showed cortical reorganizations in bilateral SMC, PMA and SMA. Therefore, it seems that the cortical reorganization in chronic hemiparetic patients can be induced by the training with the developed symmetric upper extremity motion trainer.

Toe Spreader가 경직성 뇌성마비 아동의 동적 족압 특성에 미치는 영향

신화경,태기식,Shin, Hwa-Kyung,Tae, Ki-Sik 대한물리치료학회 2010 대한물리치료학회지 Vol.22 No.1

Purpose: The purpose of this study was to determine whether there are any differences, with and without a toe spreader (TS), in dynamic foot pressure distribution in children with spastic diplegic cerebral palsy. Methods: Dynamic foot pressure recording using the RSscan system were obtained during walking in 12 participants (male=7, female=5) with and without TS. Mean force was measured for four different plantar regions; great toe, forefoot, midfoot, hindfoot. Displacement of center of pressure (COP), velocity of COP displacement and stance time were also measured during gait. Results: TS walking exhibited statistically significant decrease of mean force under great toe and forefoot (p<0.05), compared with a barefoot walking. Also, TS walking exhibited statistically significant increase of antero-posterior displacement of COP (p>0.05). Conclusion: These findings indicate the potential clinical utility of toe spreader to correct dynamic foot pressure during stance phase in children with spastic diplegic cerebral palsy.

립모션 센서 기반 증강현실 인지재활 훈련시스템을 위한 합성곱신경망 손동작 인식

송근산,이현주,태기식,Song, Keun San,Lee, Hyun Ju,Tae, Ki Sik 대한의용생체공학회 2021 의공학회지 Vol.42 No.4

In this paper, we evaluated prediction accuracy of Euler angle spectrograph classification method using a convolutional neural networks (CNN) for hand gesture recognition in augmented reality (AR) cognitive rehabilitation system based on Leap Motion Controller (LMC). Hand gesture recognition methods using a conventional support vector machine (SVM) show 91.3% accuracy in multiple motions. In this paper, five hand gestures ("Promise", "Bunny", "Close", "Victory", and "Thumb") are selected and measured 100 times for testing the utility of spectral classification techniques. Validation results for the five hand gestures were able to be correctly predicted 100% of the time, indicating superior recognition accuracy than those of conventional SVM methods. The hand motion recognition using CNN meant to be applied more useful to AR cognitive rehabilitation training systems based on LMC than sign language recognition using SVM.

가방 끈 길이 차이가 상지 근활성도, 압력중심 및 체중분포에 미치는 영향

이현주,김민수,김아연,강현구,태기식,Lee, Hyun Ju,Kim, Min Su,Kim, Ah Yeon,kang, Hyun Gu,Tae, Ki Sik 대한의용생체공학회 2021 의공학회지 Vol.42 No.5

The purpose of this study was to investigate the effect on the activity of the upper trapezius and erector spinae according to the length difference of the backpack using electromyogram (EMG). We also conducted a study comparing the center of pressure (COP) and weight distribution before and after using Wii® balance board. Thirty individuals were randomly assigned to the experimental group (n=14) wearing a backpack with a short right strap length and a control group (n=16) wearing a backpack with the same strap length. Data were collected by dividing into groups, carring a 15% weight backpack and walking for 20 minutes on a treadmill. As a result of analyzing the EMG data, there was no significant change in the upper extremity muscle activity of the control group, but it was significantly decreased in the right upper trapezius activity of the experimental group (p<0.05). In addition, there was a significant change of COP in the experimental group (p<0.05), but there was no significant difference of the weight distribution in both groups. Recognizing mechanical changes in the body that may occur due to the asymmetry of the strap length is thought to be helpful for systematic ergonomic intervention according to changes in the external environment in the future.

뇌손상 후 상지 운동기능 회복 평가: 임상적 평가 및 운동반응 근전도 분석

김영호 ( Young Ho Kim ),태기식 ( Ki Sik Tae ),송성재 ( Sung Jae Song ) 한국전문물리치료학회 2005 한국전문물리치료학회지 Vol.12 No.1

X-ray 영상에서 SegNet을 이용한 폐결핵 자동검출 시스템의 유용성 평가

이주희,안현수,최동혁,태기식,Lee, J.H.,Ahn, H.S.,Choi, D.H.,Tae, Ki Sik 대한의용생체공학회 2017 의공학회지 Vol.38 No.1

Testing TB in chest X-ray images is a typical method to diagnose presence and magnitude of PTB lesion. However, the method has limitation due to inter-reader variability. Therefore, it is essential to overcome this drawback with automatic interpretation. In this study, we propose a novel method for detection of PTB using SegNet, which is a deep learning architecture for semantic pixel wise image labelling. SegNet is composed of a stack of encoders followed by a corresponding decoder stack which feeds into a soft-max classification layer. We modified parameters of SegNet to change the number of classes from 12 to 2 (TB or none-TB) and applied the architecture to automatically interpret chest radiographs. 552 chest X-ray images, provided by The Korean Institute of Tuberculosis, used for training and test and we constructed a receiver operating characteristic (ROC) curve. As a consequence, the area under the curve (AUC) was 90.4% (95% CI:[85.1, 95.7]) with a classification accuracy of 84.3%. A sensitivity was 85.7% and specificity was 82.8% on 431 training images (TB 172, none-TB 259) and 121 test images (TB 63, none-TB 58). This results show that detecting PTB using SegNet is comparable to other PTB detection methods.

근전도, 초음파와 DITI 를 이용한 전기자극의 성인여성 복부비만 개선 효과 관찰

이현주(Hyun-Ju Lee),태기식(Ki-Sik Tae) Korean Society for Precision Engineering 2014 한국정밀공학회지 Vol.31 No.11

In this study, we investigated the improvement effect of obesity by treatment with a developed low frequency electrical stimulation system. Thirty female in their 20s as an experiment subjects divided 3 groups(control, commercialized device, developed device) were treated with electrical stimulation on abdomen for 4 weeks. The body weight, body mass index(BMI), waist-hip ratio(WHR), muscle strength, muscle(transverse abdominis(TrA), internal obliquus abdominis(IO), external obliquus abdominis(EO)), fat thickness and abdominal surface temperature were measured by electromyogram(EMG), ultrasound and digital infrared thermal image(DITI). In the result, the body weight and BMI were decreased. Subcutaneous abdominal fat were significantly reduced after 4 weeks. The muscle strength and TrA muscle thickness was increased 13.2%(p<0.05), and 35.5%, respectively. The fat thickness showed decrease in abdomen (p<0.05). Infrared measurement on abdominal surface temperature as a parameter of improvement in blood circulation was significantly increased(p<0.05). Therefore, the low frequency stimulation showed positive effects on parameters of the obesity improvement.

라플라시안 피라미드 기반 총변동 잡음제거 기법을 이용한 초음파 영상 스펙클 제거 유용성 평가

문주혜,최동혁,이수열,태기식,Moon, J.H.,Choi, D.H.,Lee, S.Y.,Tae, Ki-Sik 대한의용생체공학회 2016 의공학회지 Vol.37 No.4

The ultrasound imaging in medical diagnosis has become a popular modality because of its safe, noninvasive, portable, relatively inexpensive, and provides a real-time image formation. However, usefulness of ultrasound imaging is at times limited due to the presence of signal-dependent noise like as speckle. Therefore, noise reduction is very important, as various types of noise generated limits the effectiveness of medical image diagnosis. This paper introduces a speckle noise reduce algorithm using total variation denoising (TVD) in Laplacian pyramid. With this method, speckle is removed by TVD of bandpass ultrasound images in Laplacian pyramid domain. For TVD in each pyramid layer, a ${\lambda}$ is selected by trial-and-error method. The visual comparison of despeckled 'in vivo' ultrasound images from pancreas shows that the proposed method could effectively preserve edges and detailed structures while thoroughly suppressing speckle. For a Simulated B-mode image, contrast-to-noise-ratio (CNR) and signal-to-noise-ratio (SNR) were obtained like 4.65 dB and 14.11 dB, respectively. The results show that the proposed method can conduct better than some of the existing methods in terms of the CNR and the SNR.

고압산소챔버 중재가 알코올에 의한 산화적 스트레스 및 숙취 해소에 미치는 영향

권혁찬,박순원,조현정,강지현,이현주,태기식,Kwon, Hyeok Chan,Park, Soon Won,Cho, Hyun Jeong,Kang, Ji Hyun,Lee, Hyun Ju,Tae, Ki Sik 대한의용생체공학회 2018 의공학회지 Vol.39 No.5

The purpose of this study is to evaluate the reliability and effectiveness of hyperbaric oxygen chamber on alcohol-induced oxidative stress and hangover. In order to evaluate them, 20 healthy adults were tested for blood and hangover stress tests. When an exponential change was examined after 3 interventions (hangover drink, hyperbaric oxygen chamber, and normal chamber as placebo effect) of 1 hour, the heart rate of subjects experiencing a hyperbaric oxygen chamber showed a statistically significant decrease (p < 0.001). The tests of blood alcohol concentration (BAC) as for exquisite hematology analysis, glucose, creatinine, and AST (aspartate aminotransferase) as well as ALT (alanine aminotransferase) used as liver-damage indicator show that the hyperbaric chamber has the effective effect. In the test of lactic acid, CRP (c-reactive protein), cortisol, and creatinine, the hyperbaric chamber shows much more excellent effect than the hangover drink and normal chamber as control groups. Further studies on hyperbaric oxygen chamber intervention including this study could be very helpful for improving lives of both the patients and healthy people.