Neural Correlates of the Antinociceptive Effects of Repetitive Transcranial Magnetic Stimulation on Central Pain After Stroke

Ohn, Suk Hoon,Chang, Won Hyuk,Park, Chang-hyun,Kim, Sung Tae,Lee, Jung Il,Pascual-Leone, Alvaro,Kim, Yun-Hee SAGE Publications 2012 Neurorehabilitation and neural repair Vol.26 No.4

<P>Repetitive transcranial magnetic stimulation (rTMS) modulates central neuropathic pain in some patients after stroke, but the mechanisms of action are uncertain.</P>

Preliminary Investigation of Pain-Related Changes in Cerebral Blood Volume in Patients With Phantom Limb Pain

Seo, Cheong Hoon,Park, Chang-hyun,Jung, Myung Hun,Jang, Soyeon,Joo, So Young,Kang, Yoonkyeong,Ohn, Suk Hoon American Congress of Rehabilitation Medicine 2017 Archives of physical medicine and rehabilitation Vol.98 No.11

<P>Objective: To investigate changes in the pain network associated with phantom limb pain, magnetic resonance imaging (MRI) was used to measure cerebral blood volume (CBV) in patients who had undergone unilateral arm amputation after electrical injury.& para;& para;Design: Case-controlled exploratory MRI study of CBV via MRI.& para;& para;Setting: University hospital.& para;& para;Participants: Participants (N = 26) comprised patients with phantom limb pain after unilateral arm amputation (n = 10) and healthy, age-matched persons (n = 16).& para;& para;Interventions: Not applicable.& para;& para;Main Outcome Measures: The intensity of phantom limb pain was measured using the visual analog scale (VAS). Depressive mood was assessed using the Hamilton Depression Rating Scale, and cognitive function was assessed using the Korean version of the Mini-Mental State Examination. Voxel-wise comparisons of relative CBV maps were made between amputees and controls over the entire brain volume. The relationship between individual participant CBV (measured in voxels) and VAS score was also examined.& para;& para;Results: Compared with control participants, amputees exhibited greater degrees of depression; significantly higher CBV in the bilateral medial frontal area (orbitofrontal cortex [OFC] and pregenual anterior cingulate cortex [pACC]); and significantly lower CBV in the right midcingulate cortex, posterior cingulate cortex, and primary somatosensory cortex. CBV increased in the contralateral and ipsilateral hemispheres of the amputated arm, regardless of the amputation side. This CBV increase in the OFC and pACC was strongly correlated with pain intensity in all amputees.& para;& para;Conclusions: We observed increased CBV in regions associated with emotion in the cerebral pain network of patients who had undergone unilateral arm amputation after electrical injury. This study suggests that CBV changes were related to neuroplasticity associated with phantom limb pain. (C) 2016 by the American Congress of Rehabilitation Medicine</P>

Increased white matter diffusivity associated with phantom limb pain

Seo, Cheong Hoon,Park, Chang-hyun,Jung, Myung Hun,Baek, Seungki,Song, Jimin,Cha, Eunsil,Ohn, Suk Hoon The Korean Pain Society 2019 The Korean Journal of Pain Vol.32 No.4

Background: We utilized diffusion tensor imaging (DTI) to evaluate the cerebral white matter changes that are associated with phantom limb pain in patients with unilateral arm amputation. It was anticipated that this would complement previous research in which we had shown that changes in cerebral blood volume were associated with the cerebral pain network. Methods: Ten patients with phantom limb pain due to unilateral arm amputation and sixteen healthy age-matched controls were enrolled. The intensity of phantom limb pain was measured by the visual analogue scale (VAS) and depressive mood was assessed by the Hamilton depression rating scale. Diffusion tensor-derived parameters, including fractional anisotropy, mean diffusivity, axial diffusivity (AD), and radial diffusivity (RD), were computed from the DTI. Results: Compared with controls, the cases had alterations in the cerebral white matter as a consequence of phantom limb pain, manifesting a higher AD of white matter in both hemispheres symmetrically after adjusting for individual depressive moods. In addition, there were associations between the RD of white matter and VAS scores primarily in the hemispheres related to the missing hand and in the corpus callosum. Conclusions: The phantom limb pain after unilateral arm amputation induced plasticity in the white matter. We conclude that loss of white matter integrity, particularly in the hemisphere connected with the missing hand, is significantly correlated with phantom limb pain.

다국소 망막전위도검사의 임상적 응용

온영훈 ( Young Hoon Ohn ),안용석 ( Yong Suk Ahn ) 대한안과학회 2002 대한안과학회지 Vol.43 No.10

녹내장에서 파장가변 빛간섭단층촬영을 이용한 황반부 신경절세포층의 진단력

이응석(Eung Suk Lee),장지호(Jee Ho Chang),박태관(Tae Kwan Park),온영훈(Young Hoon Ohn),박가희(Ka Hee Park) 대한안과학회 2016 대한안과학회지 Vol.57 No.6

목적: 녹내장 환자에서 파장가변 빛간섭단층촬영(DRI OCT-1, Topcon Co., Tokyo, Japan)을 이용하여 황반부 신경절세포복합체 (macular ganglion cell complex, mGCC)와 황반 신경절세포 및 내망상층(macular ganglion cell inner plexiform layer, mGCIPL)의 두께를 분석해 보고 두 방법의 진단력을 확인해 보고자 한다. 대상과 방법: 2014년 8월부터 2015년 7월까지 본원에 내원한 109명 109안을 대상으로 파장가변 빛간섭단층촬영을 이용하여 mGCC와 mGCIPL의 두께를 측정하여 정상군, 초기, 진행된 녹내장군 간의 차이를 확인해 보고, 각각의 진단력, 민감도, 특이도를 구하여 유두주위 망막신경섬유층(circumpapillary retinal nerve fiber layer, cpRNFL) 두께 분석 방법과 비교해 보았다. 결과: 초기와 진행된 녹내장에 대한 area under the curve를 비교해 보았을 때 mGCC는 0.78과 0.99 cpRNFL과 유의한 차이가 없었으나 mGCIPL은 0.70으로 cpRNFL과 초기 녹내장을 진단하는 경우 cpRNFL의 진단력과 유의한 차이를 나타내었고(p=0.018),녹내장 진단에 대한 민감도와 특이도는 mGCC가 0.95와 0.97, mGCIPL은 0.92와 0.97로 측정되었다. 결론: 두 가지 방법 모두 녹내장을 진단하는 데 있어 높은 민감도와 특이도를 지닌 진단 방법이나, mGCC의 두께 분석 방법이 녹내장의 초기 변화를 감지하는 데 보다 나은 진단력을 가지고 있는 것으로 생각된다. <대한안과학회지 2016;57(6):941-950> Purpose: To evaluate diagnostic ability of macular ganglion cell complex (mGCC), macular ganglion cell inner plexiform layer (mGCIPL) measurements in glaucoma using swept source deep range imaging optical coherence tomography (DRI OCT-1, Topcon Co., Tokyo, Japan). Methods: From August of 2014 to July of 2015, 109 eyes of 109 subjects were assessed for the average thickness and sectional thickness of both mGCC and mGCIPL to determine whether there exists any significant difference among advanced stage glaucoma group, early stage glaucoma group and normal group in Swept source OCT. Comparisons were also made between the above measurements and circumpapillary retinal nerve fiber layer (cpRNFL) thickness measurements in their diagnostic accuracy, sensitivity, and specificity. Results: The diagnostic ability of mGCC based-mean thickness value (area under the curve [AUC] = 0.78/ 0.99) in detecting early stage glaucoma group as well as advanced stage group was not significantly different from that of cpRNFL thickness measurement. However, there was a significant difference in thickness between mGCIPL (AUC = 0.70) and cpRNFL in early stage glaucoma groups (p = 0.018). The sensitivities and specificities of mGCC were 0.95/0.97, and those of mGCIPL were 0.92/0.97, respectively. Conclusions: The two swept source OCT based methods measuring retinal ganglion cell layer thickness appeared to have a good diagnostic accuracy, high sensitivity and specificity in detecting glaucomatous eyes. Nevertheless, of the two methods, mGCC thickness measurement was more efficient in detecting early glaucomatous changes. J Korean Ophthalmol Soc 2016;57(6):941-950

뇌졸중 및 뇌손상 환자의 경관 유동식이에섬유소 첨가시 설사에 대한 효과

전세일,김동아,온석훈,조성래,서정훈,윤태준,유성,전중선,김정남,윤지영 大韓再活醫學會 2000 Annals of Rehabilitation Medicine Vol.24 No.5

A challenge of predicting seizure frequency in temporal lobe epilepsy using neuroanatomical features

Park, Chang-hyun,Ohn, Suk Hoon Elsevier 2019 Neuroscience Letters Vol.692 No.-

<P><B>Abstract</B></P> <P>The pathological and clinical characteristics of temporal lobe epilepsy (TLE) tend to be affected by epileptic seizures, specifically represented by seizure lateralization and frequency. Although the lateralization of the epileptogenic zone can be clarified in terms of neuroanatomical damage, there have been conflicting findings on the relationship between seizure frequency and neuroanatomical damage. In this study we sought to examine the relationship in the framework of machine learning-based predictive modeling. We acquired 60 grey matter (GM) anatomical features from structural MRI data and 46 white matter (WM) anatomical features from diffusion-weighted MRI data for 42 TLE patients and 45 healthy controls and applied the random forests method to the neuroanatomical features. We demonstrated that, whereas the neuroanatomical features were promising markers for the discrimination of the TLE patients from the healthy controls, the separation between the TLE patients with low and high seizure frequency on the basis of the neuroanatomical features was challenging. When we applied feature selection techniques for the construction of the predictive models, a greater number of features were selected as being relevant to the distinction of the TLE patients from the healthy controls than to the classification of the TLE patients according to seizure frequency. Furthermore, we adopted model-based clustering analysis and showed that seizure frequency-based subgroups were not matched well with neuroanatomy-based subgroups in the TLE patients. We propose that the challenge of predicting seizure frequency using neuroanatomical features could be attributable to considerable inter-individual variability in neuroanatomical damage among seizure frequency-based subgroups.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Neuroanatomical features serve as promising markers for the detection of TLE. </LI> <LI> But predicting seizure frequency using neuroanatomical features is challenging. </LI> <LI> It is due to an unclear relationship between seizure frequency and neuroanatomy. </LI> </UL> </P>

Global Synchronization Index as an Indicator for Tracking Cognitive Function Changes in a Traumatic Brain Injury Patient: A Case Report

Ho Young Lee,정광익,유우경,Suk Hoon Ohn 대한재활의학회 2019 Annals of Rehabilitation Medicine Vol.43 No.1

Traumatic brain injury is a main cause of long-term neurological disability, and many patients suffer from cognitive impairment for a lengthy period. Cognitive impairment is a fatal malady to that limits active rehabilitation, and functional recovery in patients with traumatic brain injury. In severe cases, it is impossible to assess cognitive function precisely, and severe cognitive impairment makes it difficult to establish a rehabilitation plan, as well as evaluate the course of rehabilitation. Evaluation of cognitive function is essential for establishing a rehabilitation plan, as well as evaluating the course of rehabilitation. We report a case of the analysis of electroencephalography with global synchronization index and low-resolution brain electromagnetic tomography applied, for evaluation of cognitive function that was difficult with conventional tests, due to severe cognitive impairment in a 77-year-old male patient that experienced traumatic brain injury.

Longitudinal Changes of Resting-State Functional Connectivity During Motor Recovery After Stroke

Park, Chang-hyun,Chang, Won Hyuk,Ohn, Suk Hoon,Kim, Sung Tae,Bang, Oh Young,Pascual-Leone, Alvaro,Kim, Yun-Hee Ovid Technologies Wolters Kluwer -American Heart A 2011 Stroke Vol.42 No.5

Double decussated ipsilateral corticospinal tract in schizencephaly

Chang, Won Hyuk,Kim, Young-Bum,Ohn, Suk Hoon,Park, Chang-hyun,Kim, Sung Tae,Kim, Yun-Hee Lippincott Williams Wilkins, Inc. 2009 NEUROREPORT - Vol.20 No.16

We report a patient with left hemiparesis because of schizencephaly affecting the right precentral gyrus and describe a double decussated ipsilateral corticospinal tract detected using the multimodal brain mapping technique. In this patient, we could observe that the unaffected primary motor cortex (M1) controls both hands by functional magnetic resonance imaging and motor-evoked potential study. We were also able to visualize the corticospinal tract originating from the unaffected M1 that passed through the internal capsule and cerebral peduncle on the same side. It then crossed over twice at the brain stem level to go down to the ipsilateral spinal cord. These findings show a unique pattern of brain reorganization in the recovery from early brain injury.