• 대한수의학회지
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• 제42권3호
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• pp.397-402
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• 2002

Clinical usefulness of somatosensory evoked potentials (SSEP) as a prognostic tool was evaluated with three dogs showing clinical signs associated with intervertebral disc diseases. Prior to measure SSEP, history taking, physical examination, radiological study and neurological examination were performed. In case 1, poor prognosis was predicted because deep pain was not observed and loss of sensory function was observed in SSEP. And the clinical signs persisted with the conservative treatment. However, in cases 2 and 3, good prognoses were predicted by normal conduction velocity in SSEP that meant the presence of sensory function. The clinical signs of cases 2 and 3 disappeared at days 18 and 13 after treatment, respectively. These results suggest SSEP be used clinically as a prognostic tool in dogs with intervertebral disc diseases.

• Annals of Clinical Neurophysiology
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• 제6권1호
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• pp.20-25
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• 2004

Background and Objectives: The proximal and distal nerve segments are preferentially involved in acquired demyelinating polyneuropathies (ADP). This study was undertaken in order to assess the usefulness of motor evoked potential (MEP) and somatosensory evoked potential (SSEP) in the detection of the proximal nerve lesion in ADP. Methods: MEP, SSEP and conventional NCS were performed in 6 consecutive patients with ADP (3 AIDP, 3 CIDP). MEP was recorded from abductor pollicis brevis and abductor hallucis using magnetic stimulation of the cortex and the cervical/lumbar spinal roots. SSEP were elicited by stimulating the median and posterior tibial nerves. Latency from cortex and cervical/lumbar roots, central motor conduction time (CMCT), EN1-CN2 interpeak latency were measured for comparison. Results: MEP was recorded in 24 limbs (12 upper and 12 lower limbs) and SSEP in 24 limbs (12 median nerve, 12 posterior tibial nerve). F-wave latency was prolonged in 25 motor nerves (25/34, 73.5%). Prolonged CML and PML were found in 41.7% (10/24) and 45.8% (11/24), respectively. Interside difference (ISD) of CMCT was abnormally increased in the upper extremity, 66.7% (4/6 pairs) in case of CML-PML. EN1-CN2 interpeak latency was abnormally prolonged in one median nerve (1/10) and LN1-P1 interpeak latency was normal in all posterior tibial nerves. Conclusions: MEP and SSEP may provide useful information for the proximal nerve and root lesion in ADP. MEP and SSEP is supplemental examination as well as complementary to conventional NCS.

• Annals of Clinical Neurophysiology
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• 제5권2호
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• pp.181-186
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• 2003

Background: Somatosensory evoked potential (SSEP) is valuable for the evaluation of the central pathway. However, peripheral neuropathy sometimes renders the test useless by preventing the conduction from reaching the CNS. We postulated that the peripheral conduction problems could be overcome by proximal stimulation in SSEP and wanted to verify this in the study. Methods: Twenty patients with diabetic sensorimotor polyneuropathy were included. SSEP was elicited by stimulating the median and posterior tibial nerves. We compared the effect of distal and proximal stimulations in each SSEP in the aspect of presence/absence and various latencies of resultant waves. Results: Among the 40 cases, proximal stimulation caused reappearance of subsided waves in 10 cases (25%). In the median nerve SSEP, proximal stimulation made EN1 and CN2 visible which were not evident when distally stimulated. In the posterior tibial nerve SSEP, there was also improvement of forming waves when proximally stimulated. Conclusions: In the diabetic polyneuropathy, proximal stimulation of SSEP is more effective than the conventional distal stimulation in evaluating central pathway.

• 대한물리치료과학회지
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• 제15권1호
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• pp.11-20
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• 2008

This study was designed to test the effects of comprehensive rehabilitation management on functional recovery after attack of cerebrovascular disease. 16 cerebrovascular disease patients applied comprehensive rehabilitation management of physical therapy at department of physical Therapy, C medical center in Gwang－ju. The collection of the data had been executed for 4months(April 15, 2007${\sim}$July 15, 2007). For evaluating, Functional Independence measure(FIM) and Somatosensory Evoked Potential(SSEP) were used to assess functional recovery. The results of this study were as follows: 1. In the comparison of latency of median nerve SSEP before and after treatment, the lat. N20 and P25 increased, the ampl. P25/N20 was decreased. In the comparison difference data of median nerve SSEP, however there was no significant difference in the group(p>0.05). 2. In the comparison of latency of Post Tibial nerve SSEP before and after treatment, the lat. P40, P50, P60 increased, the ampl. P40 was decreased. In the comparison difference data of post tibial nerve SSEP, however there was no significant difference in the group(p>0.05). 3. In the comparison of FIM scores of Self－care, Sphincter Control, Mobility: Transfer, Locomotion before and after treatment, the scores of FIM was significantly increased. In the comparison of difference of the motor part of FIM, however there was significant difference(p<0.05). 4. In the comparison of FIM scores of Communication, Social Cognition before and after treatment, the scores of FIM was significantly increased. In the comparison of difference of the motor part of FIM, however there was no significant difference in the group(p>0.05). Based on these results, it is concluded that the comprehensive rehabilitation management for cerebrovascular disease case was not significant difference in the SSEP, was significant difference in the motor part of FIM. Further study should be done to analyze the effect of intervention duration of treatment, optimal time to apply the treatment in more long period.

• The Journal of Korean Physical Therapy
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• 제14권4호
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• pp.64-74
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• 2002

The SSEP(SomatoSensory Evoke Potentials) test is a valid and repeatable technique which correlates with clinically assessed joint position & vibration sense, skin touch & pressure sense. Also SSEP study is a simple and quantitative test, and has been used to evaluate the sensoty system along the somatosensory pathway from peripheral sensory receptor to the cortex. The ascending pathway of SSEP has been know to be posterior column-lemniscal pathway, but not without controversy. There are two kind of test mathods : one of test is median nerve SSEP and other test is posterior tibial nerve SSEP. Recently, SSEP used to performed to evaluate the usefulness of dermatomal SSEP(D-SSEP) and segmental SSEP(5-SSEP) for the diagnosis of lumbasacral radiculopathy, and it can be measure of ingual ahd palatine evoked potentials & indicator of medullary function useful for the diagnosis of brain death.

• Journal of Korean Neurosurgical Society
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• 제30권7호
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• pp.831-841
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• 2001

Objective : Somatosensory evoked potentials(SSEPs) have been used widely both experimentally and clinically to monitor the function of central nervous system and peripheral nervous system. Studies of SSEPs have reported the various recording techniques and patterns of SSEP. The previous SSEP studies used scalp recording electrodes, showed mean vector potentials which included relatively constant brainstem potentials(far-field potentials) and unstable thalamocortical pathway potentials(near-field potentials). Even in invasive SSEP recording methods, thalamocortical potentials were variable according to the kinds, depths, and distance of two electrodes. So they were regarded improper method for monitoring of upper level of brainstem. The present study was conducted to investigate the characteristics of somatosensory evoked field potentials(SSEFPs) of the cerebral cortex that evoked by hindlimb stimulation using ball electrode and the pathways of SSEFP by recording the potentials simultaneously in the cortex, VPL nucleus of thalamus, and nucleus gracilis. Methods : In the first experiment, a specially designed recording electrode was inserted into the cerebral cortex perpendicular to the cortical surface in order to recording the constant cortical field potentials and SSEFPs mapped from different areas of somatosensory cortex were analyzed. In the second experiment, SSEPs were recorded in the ipsilateral nucleus gracilis, the contralateral ventroposterolateral thalamic nucleus(VPL), and the cerebral cortex along the conduction pathway of somatosensory information. Results : In the first experiment, we could constantly obtain the SSEFPs in cerebral cortex following the transcutaneous electrical stimulation of the hind limb, and it revealed that the first large positive and following negative waves were largest at the 2mm posterior and 2mm lateral to the bregma in the contralateral somatosensory cortex. The second experiment showed that the SSEPs were conducted by way of posterior column somatosensory pathway and thalamocortical pathway and that specific patterns of the SSEPs were recorded from the nucleus gracilis, VPL, and cerebral cortex. Conclusion : The specially designed recording electrode was found to be very useful in recording the localized SSEFPs and the transcutaneous electrical stimulation using ball electrode was effective in evoking SSEPs. The characteristic shapes, latencies, and conduction velocities of each potentials are expected to be used the fundamental data for the future study of brain functions, including the hydrocephalus model, middle cerebral artery ischemia model, and so forth.

• Journal of Korean Neurosurgical Society
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• 제29권1호
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• pp.5-14
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• 2000

Objective : Somatosensory evoked potential(SSEP) has been known to be a good method for evaluating brain stem function, but it is not sufficient to check the fine changes of cortical functions. A fine change of cortical function can be expressed with somatosensory evoked cortical field potential(SSEFP) rather than general SSEP. To confirm the usefulness of SSEFP for evaluating the cortical function, the authors simultaneously measured SSEFP and the intracranial pressure-volume index(PVI) in kaolin-induced hydrocephalic rats. Method : Hydrocephalus was induced with injection of 0.1ml kaolin-suspended solution into the cisterna magna in 60 Sprague-Dawley rats. The authors measured PVI and SSEFP 1 week after injection of kaolin-suspended solution. To evaluate the severity of induced hydrocephalus, we measured the transverse diameter of the lateral ventricle on the coronal slice of the rat brain 0.40mm posterior to the bregma. Result : The typical wave form of SSEFP in control rats showed a negative-positive complex wave at early latency. In SSEFP of normal rats, N0 is 10.0 msec, N1 15.3 msec, P1 31.2 msec and N1-P1 amplitude $15.4{\mu}V$. As hydrocephalus progressed, the peak latency of N1 and P1 were delayed. In mild hydrocephalus, negative peak waves were split. The N1-P1 amplitude was decreased only in severe hydrocephalus. The changes of the characteristics of SSEFP according to the severity of hydrocephalus were well correlated with the changes of PVI. Shunting normalized the characteristics of SSEFP in relation to ventricular sizes and PVI in hydrocephalic rats. Conclusion : SSEFP may be useful for evaluating the impairment of cortical function in hydrocephalus.

• Journal of Yeungnam Medical Science
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• 제18권1호
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• pp.67-74
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• 2001

정상 성인 남녀 36명(남:여=23:13)을 대상으로 LFCN의 SSEP검사를 시행한 결과로서 다음과 같은 결론을 얻을 수 있었다. 1. MP의 진단에 있어서는 $P_0$, $N_1$의 절대잠복기 뿐만 아니라 좌 우측 잠복기의 차이값($DP_0$, $DN_1$을 비교하여 보는 것이 더욱 중요하며 그 차이는 모두 2 msec 이하였다. 2. $P_0N_1$의 진폭만으로 비정상과 정상의 기준을 정할 수는 없으나 좌 우측 평균 진폭의 차이는 1.6배 이하였다. 3. $P_0(N_1)$, $DP_0(DN_1)$, 그리고 A(DA)에 있어 남녀군 간의 차이는 없었다.

• Annals of Clinical Neurophysiology
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• 제16권2호
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• pp.62-69
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• 2014

Background: Neuromodulation therapy has been used to an adjunctive treatment promoting motor recovery in stroke patients. The objective of the study was to determine the effect of repetitive transcranial magnetic stimulation (rTMS) on neurobehavioral recovery and evoked potentials in rats with middle cerebral artery occlusion. Methods: Seventy Sprague-Daley rats were induced permanent middle cerebral artery occlusion (MCAO) stroke model and successful stroke rats (n=56) assigned to the rTMS (n=28) and sham (n=28) group. The 10 Hz, high frequency rTMS gave on ipsilesional forepaw motor cortex during 2 weeks in rTMS group. The somatosensory evoked potential (SSEP) and motor evoked potential (MEP) were used to evaluate the electrophysiological changes. Behavioral function of the stroke rat was evaluated by the Rota rod and Garcia test. Results: Forty rats ($N_{rTMS}=20;\;N_{sham}=20$) completed all experimental course. The rTMS group showed better performance than sham group in Rota rod test and Garcia test at day 11 (p<0.05) but not day 18 (p>0.05). The amplitude of MEP and SSEP in rTMS group was larger than sham group at day 18 (p<0.05). Conclusions: These data confirm that the high frequency rTMS on ipsilesional cerebral motor cortex can help the early recovery of motor performance in permanent middle cerebral artery stroke model and it may simultaneously associate with changes in neurophysiological activity in brain.

• Journal of Korean Neurosurgical Society
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• 제30권sup2호
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• pp.281-288
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• 2001

Objectives : The purpose of this study is to evaluate the usefulness of SSEP monitoring during intracranial aneurysm surgery and compare the characteristics of wave change in relation to neurologic changes between ACA aneurysms and MCA aneurysms. Methods : During recent three years(between January 1997 and November 1999), intraoperative SSEP monitoring had been done in 63 operations for intracranial aneurysms. We had monitored the median nerve SSEP during surgery for aneurysms of MCA and the posterior tibial nerve SSEP for aneurysms of ACoA or ACA. A more than 50% reduction of any cortical SEP response was considered to be a significant SEP change, compared to its baseline value before the start of surgery. Changes in the SEPs were categorized as follows : Type IA, no significant amplitude changes without temporary clipping ; Type IB, no significant amplitude changes with temporary clipping ; Type II, significant changes with temporary clipping and complete return to control amplitude ; Type III, significant changes with temporary clipping and incomplete return to control amplitude ; Type IV, significant changes with temporary clipping and more decreased amplitude changes. Results : Among the 63 intraoperative monitoring, there were 37 cases of ACA aneurysms(An), and 26 of MCA An. The temporary proximal arterial occlusion during surgery were performed in 31(83.8%)cases of ACA An, 22(84.6%) of MCA An. Seven of the 31 ACA An(22.6%) and ten of the 22 MCA An(45.5%) had significant changes. The type were as follows : 4 patients with type II and 3 with type III in the ACA An ; 3 patients with type II and 3 with type III and 4 with type IV in the MCA An. In both group type II changes had no new postoperative neurological deficit. All 6 patients with type III had new neurological deficits ; However, One case in the ACA An and two cases in the MCA An. had transient neurologic deficit and improved markedly over the next two months. All 4 type IV changes in the MCA An. had permanant neurologic deficits. Two out of 30 cases(6.7%) in the ACA An. and one out of 16 cases(6.3%) in the MCA An. without significant amplitude change had new neurologic deficit postoperatively. Conclusion : Based on this study, Intraoperative SSEP monitoring during aneurysm surgery would provide useful information for detecting cerebral ischemia. SSEP response during surgery for MCA An. is more sensitive than ACA An. Otherwise, there were no meaningful difference in rate of false negativity.