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P32-25 Multimodal evoked potentials in myotonic dystrophies MD1 and MD2
S298
Posters
most serious manifestation of cervical spondylosis and is the commonest cause of myelopathy over 60. Some tests are necessary to diagnosis of this illness: clinical evaluation, electrodiagnostic and imagenologycal tests. Electrodiagnostic tests are very useful to demonstrate the location and intensity of lesion, functional disability and prognosis. Objects: We propose demonstrate the different damage of electrophysiologycal parameters in CSM and describe it. Methods: 30 patients f both sex with CSM confirmed by MRI were studied. Nerve conduction study and F wave of median nerve were applied to them. We also evaluated EMG, Somatosensory and Motor Evoked Potentials. We applied descriptive statistical techniques to electrophysiologycal parameters, and also we correlated them with cord compression that was showed by MR. Results: Motor evoked potentials were the most affected. Its suggested that corticospinal tracts are affected early and in most intense form. Electrophysiologycal parameters were affected in different form: motor evoked potential amplitude was decrease in 69.5 percent, motor evoked potential amplitude ratio was decrease in 78 percent and P40 wave latency was increase in 52.1 percent of patients. Electromiography was affected in all patients; in 72.7 percent of them it showed diffuse neurogenic pattern and in the rest of them it showed radicular pattern. We also demonstrate moderate or several abnormalities of motor and sensory nerve conduction of median nerve in 52.1 percent of the patients. There was a great correlation between electrophysiologycal parameters abnormalities and intensity of MRI cord damage. Conclusions: Motor Evoked parameters are most affected in CSM. There is involvement of median nerve in an important group of CSM patients. Its an overlapping abnormality. There is a great correlation between abnormalities of electrophysiologycal parameters and MRI damage of the cord. P32-23 An evaluation method for EEG amplifiers’ performance H. Higa1 , T. Soken1 , H. Uehara1 , S. Suwazono2 Faculty of Engineering, University of the Ryukyus, Okinawa, Japan, 2 National Hospital Organization Okinawa National Hospital, Okinawa, Japan 1
Objective: The electroencephalogram (EEG) can be used by people with severe disabilities to communicate with their environment. A direct connection between the brain and the computer is well known as an EEG-based brain-computer interface (BCI). The final goal of our study is to provide people suffering from neuromuscular disease with the EEG-based BCI system. As our first step, we made a new amplifier for the BCI system. The performances of the amplifier and two other EEG measurement systems were compared experimentally. Methods: A sinusoidal signal with frequency of 10 Hz and peak-topeak amplitude of 25 mV, which was generated by Patient Simulator, Compumedics, was applied to the amplifier we made as well as two conventionally available EEG measurement systems. For each system, the signal was sampled at a frequency of 1 kHz by using an AD converter, and was filtered with a 100-Hz low pass digital filter. Signal to noise (S/N) ratios of the data recorded by these measurement systems were calculated as follows. In the first step, a 10-Hz signal component was subtracted from the recorded data. We assumed that the resultant data were equivalent to the noise component in the recorded data. The ratio of the 10-Hz component and the noise component was then calculated in the next step. Results: It can be seen from the experimental results that the amplifier has better S/N ratio than the other systems have. Conclusions: This method would be one of options to improve the performance of the amplifier for EEG measurement. P32-24 Poorman’s ERP/EP lab. EP/ERP, version 0.9
yet another free analysis software for
S. Suwazono1 , H. Arao2 Division of Neurology, National Hospital Organization Okinawa Hospital, Ginowan, Japan, 2 Department of Kansei Design, Faculty of Psychological Science Hiroshima International University, Higashi-Hiroshima, Japan 1
Objective: To develop a free software for EP/ERP analysis.
Methods: Perl scripts were developed from scratch (Practical Extraction and Report Language, www.perl.org). Minimum requirements were Perl5.8 and Gnuplot. Results: Following analysis steps are supported by the current software; (1) importing ascii file (CSV format), recorded by Nihon-Kohden electroencephalograph, (2) epoching, determined by square pulse trigger in any channel, (3) artifact rejection by visual inspection each epoch can be visually reviewed to determine whether it should be included in the average or not, (4) averaging all the accepted epochs. The analysis results of dummy data were validated with the results using a commercial software. Conclusions: Pros of the analysis system include; (1) free, (2) each step is visible to all users and can be changed easily, (3) Many operating systems are supported as far as Perl and Gnuplot is available (including Unix, Mac OSX, Windows). Cons include; (1) poor interface (command line interface only), (2) slow graphics for multichannel display, (3) no automatic average yet, (4) no filtering yet, (5) no scalp distribution maps yet. P32-25 Multimodal evoked potentials in myotonic dystrophies MD1 and MD2 M. Banach1 , M. Rakowicz1 , G. Witkowski1 , M. Derejko1 , M. Niewiadomska1 , E. Waliniowska1 , E. Ingot1 , M. Wie˛cławska1 , U. Zalewska1 1 Department of Psychiatry and Neurology, Institute of Psychiatry and Neurology Warsaw, Poland Background: Myotonic dystrophies MD1 and MD2 are multisystem diseases with numerous symptoms and high interfamily variability, resulting from the fact that different organs are affected. Until now the mechanisms that lead to the damage of the central system have not been fully understood. The aim of this study was to assess the frequency of abnormal multimodal evoked potential and electrophysiological evaluation of the central nervous system involvement in MD1 and MD2. Methods: Standard evoked potential (EP) was used to study the visual, auditory and somatosensory pathways in 20 patients with genetically confirmed DM1 and 6 patients with DM2. Results: Electrophysiological examination confirmed clinical or subclinical abnormalities of the central nervous system (CNS) in 24 out of 26 of patients. Of these, abnormal visual pathways (20/26) were the most common. Less frequently abnormal were brainstem auditory pathways (5/26). Somatosensory pathways were abnormal only in 3/26 patients. Conclusion: Central nervous system (CNS) abnormalities have been reported in various primary muscle diseases, including myotonic dystrophy. Our abnormal findings suggest that pattern visual-evoked potentials can detect subclinical dysfunction of the visual pathways. VEP, which detects both demyelination (increased latency) and neural degeneration (reduced amplitude), revealed more abnormality than VEP or SSEP in DM1 and DM2 patients. P33. MEG (Basic studies) P33-1 Characteristics of sensori-motor interaction in the primary and secondary somatosensory cortices in humans: an MEG study T. Wasaka1 , T. Kida1 , R. Kakigi1 1 Department of Integrative Physiology, National Institute for Physiological Sciences, Japan Objective: To elucidate the mechanism of sensorimotor interaction in somatosensory system, we studied the activities in the primary (SI) and secondary somatosensory cortex (SII) using magnetoencephalography. Methods: Four tasks were performed in which a voluntary thumb movement of the left or right hand was combined with electrical stimulation applied to the index finger of the left or right hand: L(M)-L(S) (movement of the left thumb triggered stimulation to the left finger), L(M)-R(S), R(M)-R(S), and R(M)-L(S). Stimulation to the index finger only (S condition) was also recorded. Since SII in both hemispheres was activated following unilateral stimulation, we analyzed SIIc (contralateral to stimulation) as well as SIIi (ipsilateral to stimulation). Results: In SI, the amplitude of N20m and P35m was significantly attenuated in the R(M)-R(S) and L(M)-L(S) tasks compared with the S condition, but that for other tasks showed no change, corresponding to a conventional gating phenomenon. In SII, the R(M)-L(S) task significantly enhanced the amplitude of SIIc but reduced that of SIIi compared with
Posters
most serious manifestation of cervical spondylosis and is the commonest cause of myelopathy over 60. Some tests are necessary to diagnosis of this illness: clinical evaluation, electrodiagnostic and imagenologycal tests. Electrodiagnostic tests are very useful to demonstrate the location and intensity of lesion, functional disability and prognosis. Objects: We propose demonstrate the different damage of electrophysiologycal parameters in CSM and describe it. Methods: 30 patients f both sex with CSM confirmed by MRI were studied. Nerve conduction study and F wave of median nerve were applied to them. We also evaluated EMG, Somatosensory and Motor Evoked Potentials. We applied descriptive statistical techniques to electrophysiologycal parameters, and also we correlated them with cord compression that was showed by MR. Results: Motor evoked potentials were the most affected. Its suggested that corticospinal tracts are affected early and in most intense form. Electrophysiologycal parameters were affected in different form: motor evoked potential amplitude was decrease in 69.5 percent, motor evoked potential amplitude ratio was decrease in 78 percent and P40 wave latency was increase in 52.1 percent of patients. Electromiography was affected in all patients; in 72.7 percent of them it showed diffuse neurogenic pattern and in the rest of them it showed radicular pattern. We also demonstrate moderate or several abnormalities of motor and sensory nerve conduction of median nerve in 52.1 percent of the patients. There was a great correlation between electrophysiologycal parameters abnormalities and intensity of MRI cord damage. Conclusions: Motor Evoked parameters are most affected in CSM. There is involvement of median nerve in an important group of CSM patients. Its an overlapping abnormality. There is a great correlation between abnormalities of electrophysiologycal parameters and MRI damage of the cord. P32-23 An evaluation method for EEG amplifiers’ performance H. Higa1 , T. Soken1 , H. Uehara1 , S. Suwazono2 Faculty of Engineering, University of the Ryukyus, Okinawa, Japan, 2 National Hospital Organization Okinawa National Hospital, Okinawa, Japan 1
Objective: The electroencephalogram (EEG) can be used by people with severe disabilities to communicate with their environment. A direct connection between the brain and the computer is well known as an EEG-based brain-computer interface (BCI). The final goal of our study is to provide people suffering from neuromuscular disease with the EEG-based BCI system. As our first step, we made a new amplifier for the BCI system. The performances of the amplifier and two other EEG measurement systems were compared experimentally. Methods: A sinusoidal signal with frequency of 10 Hz and peak-topeak amplitude of 25 mV, which was generated by Patient Simulator, Compumedics, was applied to the amplifier we made as well as two conventionally available EEG measurement systems. For each system, the signal was sampled at a frequency of 1 kHz by using an AD converter, and was filtered with a 100-Hz low pass digital filter. Signal to noise (S/N) ratios of the data recorded by these measurement systems were calculated as follows. In the first step, a 10-Hz signal component was subtracted from the recorded data. We assumed that the resultant data were equivalent to the noise component in the recorded data. The ratio of the 10-Hz component and the noise component was then calculated in the next step. Results: It can be seen from the experimental results that the amplifier has better S/N ratio than the other systems have. Conclusions: This method would be one of options to improve the performance of the amplifier for EEG measurement. P32-24 Poorman’s ERP/EP lab. EP/ERP, version 0.9
yet another free analysis software for
S. Suwazono1 , H. Arao2 Division of Neurology, National Hospital Organization Okinawa Hospital, Ginowan, Japan, 2 Department of Kansei Design, Faculty of Psychological Science Hiroshima International University, Higashi-Hiroshima, Japan 1
Objective: To develop a free software for EP/ERP analysis.
Methods: Perl scripts were developed from scratch (Practical Extraction and Report Language, www.perl.org). Minimum requirements were Perl5.8 and Gnuplot. Results: Following analysis steps are supported by the current software; (1) importing ascii file (CSV format), recorded by Nihon-Kohden electroencephalograph, (2) epoching, determined by square pulse trigger in any channel, (3) artifact rejection by visual inspection each epoch can be visually reviewed to determine whether it should be included in the average or not, (4) averaging all the accepted epochs. The analysis results of dummy data were validated with the results using a commercial software. Conclusions: Pros of the analysis system include; (1) free, (2) each step is visible to all users and can be changed easily, (3) Many operating systems are supported as far as Perl and Gnuplot is available (including Unix, Mac OSX, Windows). Cons include; (1) poor interface (command line interface only), (2) slow graphics for multichannel display, (3) no automatic average yet, (4) no filtering yet, (5) no scalp distribution maps yet. P32-25 Multimodal evoked potentials in myotonic dystrophies MD1 and MD2 M. Banach1 , M. Rakowicz1 , G. Witkowski1 , M. Derejko1 , M. Niewiadomska1 , E. Waliniowska1 , E. Ingot1 , M. Wie˛cławska1 , U. Zalewska1 1 Department of Psychiatry and Neurology, Institute of Psychiatry and Neurology Warsaw, Poland Background: Myotonic dystrophies MD1 and MD2 are multisystem diseases with numerous symptoms and high interfamily variability, resulting from the fact that different organs are affected. Until now the mechanisms that lead to the damage of the central system have not been fully understood. The aim of this study was to assess the frequency of abnormal multimodal evoked potential and electrophysiological evaluation of the central nervous system involvement in MD1 and MD2. Methods: Standard evoked potential (EP) was used to study the visual, auditory and somatosensory pathways in 20 patients with genetically confirmed DM1 and 6 patients with DM2. Results: Electrophysiological examination confirmed clinical or subclinical abnormalities of the central nervous system (CNS) in 24 out of 26 of patients. Of these, abnormal visual pathways (20/26) were the most common. Less frequently abnormal were brainstem auditory pathways (5/26). Somatosensory pathways were abnormal only in 3/26 patients. Conclusion: Central nervous system (CNS) abnormalities have been reported in various primary muscle diseases, including myotonic dystrophy. Our abnormal findings suggest that pattern visual-evoked potentials can detect subclinical dysfunction of the visual pathways. VEP, which detects both demyelination (increased latency) and neural degeneration (reduced amplitude), revealed more abnormality than VEP or SSEP in DM1 and DM2 patients. P33. MEG (Basic studies) P33-1 Characteristics of sensori-motor interaction in the primary and secondary somatosensory cortices in humans: an MEG study T. Wasaka1 , T. Kida1 , R. Kakigi1 1 Department of Integrative Physiology, National Institute for Physiological Sciences, Japan Objective: To elucidate the mechanism of sensorimotor interaction in somatosensory system, we studied the activities in the primary (SI) and secondary somatosensory cortex (SII) using magnetoencephalography. Methods: Four tasks were performed in which a voluntary thumb movement of the left or right hand was combined with electrical stimulation applied to the index finger of the left or right hand: L(M)-L(S) (movement of the left thumb triggered stimulation to the left finger), L(M)-R(S), R(M)-R(S), and R(M)-L(S). Stimulation to the index finger only (S condition) was also recorded. Since SII in both hemispheres was activated following unilateral stimulation, we analyzed SIIc (contralateral to stimulation) as well as SIIi (ipsilateral to stimulation). Results: In SI, the amplitude of N20m and P35m was significantly attenuated in the R(M)-R(S) and L(M)-L(S) tasks compared with the S condition, but that for other tasks showed no change, corresponding to a conventional gating phenomenon. In SII, the R(M)-L(S) task significantly enhanced the amplitude of SIIc but reduced that of SIIi compared with