• 한국의학물리학회지:의학물리
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• 제17권3호
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• pp.159-166
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• 2006

기능성 자기공명영상을 이용하여 진동자극에 대한 감각피질의 비선형성에 대하여 연구하였다. 진동자극은 25 Hz의 주파수로 5개의 각기 다른 진동 자극 기간, 2초, 4초, 8초, 12초 그리고 16초와 함께 20초의 무자극 주기와 pseudo-random순서로 구성되었다. 감각피질에 대한 자극 기간의 변화에 따른 선형성을 이해하기 위하여 두 다른 방법(시스템의 선형성 조사법과 gamma-variate 함수를 적용하여 impulse response함수를 구하는 방법)을 사용하여 혈류반응 함수를 분석하였는데, 그 결과는 거의 비슷하였다. 감각피질에서의 BOLD 반응은 8초보다 작은 자극 기간 동안에는 비선형이고 8초 이상일 때는 선형성을 보였다. 자극 기간의 함수로 Impulse response 함수의 진폭, 면적, 피크까지의 시간, FWHM을 계산하였고 진폭과 면적의 크기는 자극 기간이 증가할 때 감소함을 보여줌으로써 자극 기간 8초에서 BOLD 반응이 비선형성에서 선형성으로 변함을 뒷받침해 주었다.

• Investigative Magnetic Resonance Imaging
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• 제3권1호
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• pp.47-52
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• 1999

목적 : 시각자극을 이용하여 대뇌 후두엽에서 BOLD(blood oxygen level dependent)효과에 의한 기능적 자기공명영상과 양성자 자기공명분광법을 이용한 대사물질영상( metabolic i image)을 얻어 그 결과를 평가하고자 하였다. 대상 및 방법 : 24세에서 30세 사이의 8명의 남자와 2명의 여자를 포함하는 10명의 정상 성인 남녀를 대상으로 1.5T MRI에서 시각 지극을 이용하여 echo planar imaging펠스시퀀스를 사용하여 BOLD효과에 의한 영상들을 대뇌 후두엽에서 얻었다. 시각자극은 8Hz의 red flicker를 이용한 광 자극을 주였다. MR에서 얻어진 영상들을 workstation으로 전송한 뒤 자체 개발한 분석프로그램을 사용하여 상관계수방법을 이용하여 기능적 영상을 구하였다. 그리고 얻어진 영상의 활성화 부위를 선정한 뒤 양성자 자기공명 분광법을 사용하여 시각 자극에 의한 뇌 활성화시 대사물질의 변화를 분석했다. 그 후 자가공명분광영상법(magnetic resonance spectro-scopic imaging)를 실행하여 젖산(lactate)의 대사물질 영상을 얻었다. 결과 : 시각 자극에 따른 BOLD효과에 의한 뚜렷한 활성화 부위가 후두염 대뇌피질에 나타났다. 또한 이들 활성화 부위에서 자기공명분광법을 시행한 결과 휴식상태와 시각자극상태에서 NAA(N-acetyle aspartate)/Cr(creatine)이 $1.79{\pm}0.28$에서 $1.88{\pm}O.20$으로 거의 변화가 없는 것에 반해 lactate는 자극 전후 $9.48{\pm}4.38$배로 증가하였으며 이를 바탕으로 lactate에 대한 대사물질영상을 얻을 수 있었다. 결론 : 시각자극에 의한 뇌 활성화시 BOLD효과를 이용한 자기공명영상볍으로 활성화 부위를 확인할 수 있었고, 같은 부위에서 자기공명분광법을 이용하여 lactate의 증가를 확인하였다. 또한 lactate의 증가를 대사물질영상으로 표현함으로써 두 결과에 대한 상관관계 및 뇌 기능적영상에 대한 신뢰성을 높일 수 있게 되었다.

• Journal of Korean Neurosurgical Society
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• 제54권6호
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• pp.453-460
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• 2013

Objective : There is a rich literature confirming the default mode network found compatible with task-induced deactivation regions in normal subjects, but few investigations of alterations of the motor deactivation in patients with intracranial lesions. Therefore, we hypothesized that an intracranial lesion results in abnormal changes in a task-induced deactivation region compared with default mode network, and these changes are associated with specific attributes of allocated regions. Methods : Blood oxygenation level dependent (BOLD) functional magnetic resonance imaging (fMRI) during a motor task were obtained from 27 intracranial lesion patients (mean age, 57.3 years; range 15-78 years) who had various kinds of brain tumors. The BOLD fMRI data for each patient were evaluated to obtain activation or deactivation regions. The distinctive deactivation regions from intracranial lesion patients were evaluated by comparing to the literature reports. Results : There were additive deactivated regions according to intracranial lesions : fusiform gyrus in cavernous hemangioma; lateral occipital gyrus in meningioma; crus cerebri in hemangiopericytoma; globus pallidus, lateral occipital gyrus, caudate nucleus, fusiform gyrus, lingual gyrus, claustrum, substantia nigra, subthalamic nucleus in GBM; fusiform gyrus in metastatic brain tumors. Conclusion : There is increasing interest in human brain function using fMRI. The authors report the brain function migrations and changes that occur in patients with intracranial lesions.

• 한국의학물리학회:학술대회논문집
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• 한국의학물리학회 2003년도 제27회 추계학술대회
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• pp.75-75
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• 2003

Purpose: To investigate whether or not acupuncture of GB34 produces a significant response of the modulation of somatomotor areas by functional magnetic resonance imaging (fMRI) study. Methods: The acupoint, GB34, located in the back of the knee, is known to be effective in recovering motor function after stroke. Using 3T MRI scanner, functional MR imaging of the whole brain was performed in 12 normal healthy subjects during two stimulation paradigms; acupuncture manipulation on GB 34 and sham points. This study investigates the activation of the motor cortex elicited by a soft and an intensified stimulation of GB 34. Three different paradigms were carried out to detect any possible modulation of the Blood Oxygenation Level Dependent (BOLD) response in the somatomortor area to motor stimulation through acupuncture. Results: Group analysis from seven individuals showed that bilateral sensorimotor areas (BA 3,4,6 and 7) showed stimulation related BOLD signal contrast of approximately 6% whereas very few areas were activated when sham stimulation is given. Conclusions: The present study shows that acupuncture fMRI study can be safely conducted in 3T MRI environment, and acupuncture stimulation in GB34 modulates the cortical activities of the soma- to motor area in human. The present findings may shed light on the CNS mechanism of motor function by acupuncture and form a basis for future investigations of motor modulation circuits in the stroke patients. Acknowledgement: This study was supported by a grant of the Mid and Long Term Nuclear RID Plan Program, Ministry of Science and Technology, Republic of Korea.

• 한국의학물리학회:학술대회논문집
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• 한국의학물리학회 2002년도 Proceedings
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• pp.352-355
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• 2002

The purpose of this study was to investigate whether or not acupuncture of GB34 produces a significant response of the modulation of somatomotor areas by functional magnetic resonance imaging (fMRI) study. The acupoint, GB34, located in the back of the knee, is known to be effective in recovering motor function after stroke. Using 3T MRI scanner, functional MR imaging of the whole brain was performed in 12 normal healthy subjects during two stimulation paradigms; acupuncture manipulation on GB 34 and sham points. This study investigates the activation of the mortor cortex elicited by a soft and an intensified stimulation of GB 34. Three different paradigms were carried out to detect any possible modulation of the Blood Oxygenation Level Dependent (BOLD) response in the somatomortor area to motor stimulation through acupuncture. Group analysis from seven individuals showed that bilateral sensorimotor areas (BA 3,4,6 and 7) showed stimulation related BOLD signal contrast of approximately 6% whereas very few areas were activated when sham stimulation is given. The present study shows that acupuncture fMRI study can be safely conducted in 3T MRI environment, and acupuncture stimulation in GB34 modulates the cortical activities of the somatomotor area in human. The present findings may shed light on the CNS mechanism of motor function by acupuncture and form a basis for future investigations of motor modulation circuits in the stroke patients.

• 한국산학기술학회논문지
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• 제13권12호
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• pp.5860-5866
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• 2012

BOLD기법은 자극 횟수가 늘어날수록 시간의 증가 및 검사 실패율이 높아지므로 본 연구를 통해 가장 적절한 자극 횟수를 도출하여 제시함을 목적으로 하였다. 연구대상은 정상인 10명을 대상으로 손 운동 기능검사의 paradigm을, 1회에서 7회까지 자극 횟수로 나누어 피검자에게 시행하였다. 실험장비는 Philips Intera Archieva 3.0T MRI System 및 Invivo사의 Eloquene를 사용하였으며, BOLD-EPI 기법을 이용하여 10번의 휴지기와 10번의 활성기의 block design을 이용하였다. 관심영역인 primary hand motor area의 활성화 여부와 활성화 cluster 수, 활성화도, 비관심영역의 활성화 cluster 수를 비교하였다. 관심영역의 활성화 cluster 수는 2회 자극이 가장 낮았고, 3회부터는 일정하였으며, 활성화도는 자극 횟수가 늘어날수록 증가하지만, 비례하지는 않았다. 비관심 영역의 활성화 cluster 수는 3회부터 일정하였고, 6회부터 다시 증가하였다. 결론적으로 관심영역과 비관심영역의 활성화를 감안하고, 시간 감소에 따른 환자의 피로를 감소시키면서 정확성에 영향을 주지 않는 자극 횟수로 3회가 적정하리라 사료된다.

• 한국자기공명학회논문지
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• 제6권2호
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• pp.89-93
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• 2002

We report a preliminary fMRI evidence of modulation of somatomotor areas by acupuncture in GB34 acupoint. GB34, located in the back of the knee, is known to be effective in recovering motor function after stroke. Using 3T MR scanner, functional MR imaging was performed in five normal volunteers in two stimulation paradigms; acupuncture manipulation on GB34 and sham points. Group analysis form five individuals showed that bilateral sensorimotor areas (BA 3,4,6 and 7) showed stimulation related BOLD signal contrast of approximately 6% whereas very few areas were activated when sham stimulation is given. Our results suggest that acupuncture fMRI study can be safely conducted in 3T environment and stimulation in GB34 modulate the cortical activities of the somatomotor area in human.

• 한국자기공명학회:학술대회논문집
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• 한국자기공명학회 2002년도 International Symposium on Magnetic Resonance
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• pp.21-25
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• 2002

We report a preliminary fMRI evidence of modulation of somatomotor areas by acupuncture in GB34 acupoint. GB34, located in the back of the knee, is known to be effective in recovering motor function after stroke. Using 3T MR scanner, functional MR imaging was performed in five normal volunteers in two stimulation paradigms; acupuncture manipulation on GB34 and sham points. Group analysis from five individuals showed that bilateral sensorimotor areas (BA 3,4,6 and 7) showed stimulation related BOLD signal contrast of approximately 6％ whereas very few areas were activated when sham stimulation is given. Our results suggest that acupuncture fMRI study can be safely conducted in 3T environment, and stimulation in GB34 modulate the cortical activities of the somatomotor area in human.

• Journal of Acupuncture Research
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• 제18권5호
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• pp.60-69
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• 2001

Objective : Recent studies Suggested that there is a strong correlation between acupuncture stimulation and its related cortical activation. Anther study showed that either positive or negative BOLD effects could be observed depending on anatomical structure in acupuncture. Material and Methods : 1) Subjects and paradigms : Two separate stimulation paradigms were performed on five healthy (aged 22-23 yrs) in this study. First, the paradigm of acupuncture stimulation was that the acupuncture needle was inserted in acupoints KI6(照海), which is located in lateral side of the foot and then continuously twisted(補瀉를 除外한 捻轉法) for 70 seconds for 10 cycles of activation. During rest period (70 seconds), the needle was completed removed from acupoint. Total 60 cycles were performed and 10 images were obtained per cycle. Second, non-acupoint was randomly selected and the same paradigm was performed as acupoint stimulation. The stimulation protocol comprised 10 cycles of alternating activation and rest (10 images per cycle). Total 60 cycles were performed and each cycle take about 1.5 sec for motor task. Subjects take an at least 15 minutes break before starting anther paradigm. Conclusion : In this study, I investigated a new acupoint KI6(照海) which was known as motor - related acupoint and obtained an evidence that the stimulation of KI6(照海) resulted in negative BOLD response to stimulation.

• Journal of Acupuncture Research
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• 제20권4호
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• pp.66-84
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• 2003

Objectve : Recent stuides suggested that there is a strong correlation between acupuncture stimulation and its cortical activation. Another study showed that either positive or negative BOLD effects could be observed depending on anatomical structure in acupuncture. Methods : 1) Subjects and paradigms: Two separate stimulation paradigms were performed in this study. To see the effects of electro-acupuncture stimulation on K7(Fuliu), the experiment was carried out on six healthy volunteers, using the gradient echo sequence with the 3.0T whole-body MRI system(ISOL). After the needle insertion on right K7(Fuliu), 2 Hz of electric stimulation was given for 30 seconds, repeated five times, with 30 seconds' intervals. During the intervals while there was no electro-stimulation, the subjects performed motor task as a reference. The image analysis including motion correction, talairach transformation, and smoothing was done using SPM99. Results: The electro-acupuncture stimulation on K7(Fuliu) activated Brodmann's Areas of 9, 19, 23, 24, 31, 32, 39 which may be the central pathways of the electro-acupuncture stimulation on K7(Fuliu) and those brain areas may be related with the function of the electro-acupuncture stimulation on K7(Fuliu).