Katsuya Kobayashi1, Takefumi Hitomi2, Riki Matsumoto3, Takayuki Kondo1, Jun Kawamata1, Masao Matsuhashi4, Shuji Hashimoto5, Hitoshi Ikeda6, Yasumichi Koide6, Yushi Inoue6, Ryosuke Takahashi1, Akio Ikeda7. 1. Department of Neurology, Kyoto University Graduate School of Medicine, Japan. 2. Department of Neurology, Kyoto University Graduate School of Medicine, Japan; Department of Respiratory Care and Sleep Control Medicine, Kyoto University Graduate School of Medicine, Japan. 3. Department of Neurology, Kyoto University Graduate School of Medicine, Japan; Department of Epilepsy, Movement Disorders and Physiology, Kyoto University Graduate School of Medicine, Japan. 4. Human Brain Research Center, Kyoto University Graduate School of Medicine, Japan. 5. Department of Neurology, Tenri Hospital, Japan. 6. National Epilepsy Center, Shizuoka Institute of Epilepsy and Neurological Disorders, Japan. 7. Department of Neurology, Kyoto University Graduate School of Medicine, Japan; Department of Epilepsy, Movement Disorders and Physiology, Kyoto University Graduate School of Medicine, Japan. Electronic address: akio@kuhp.kyoto-u.ac.jp.
Abstract
PURPOSE: To delineate chronological changes of cortical hyperexcitability by long-term follow-up of the amplitudes of somatosensory evoked potentials (SEPs) in patients with Japanese Unverricht-Lundborg disease (ULD). METHOD: SEPs to median nerve stimulation were repeatedly examined in 7 genetically diagnosed ULD patients with the mean interval of 11.9 years. The degree of temporal changes in the amplitude of 3 early cortical components, N20, P25 and N35, to the age was analyzed and compared with that of healthy subjects. RESULTS: Their clinical course was almost stable during the follow-up period, namely cessation of generalized tonic-clonic seizures and little or no progression of myoclonus. SEP amplitudes of P25 and N35 were enlarged in all patients and were gradually decreased with aging in ULD on average. The degree of temporal changes of P25 and N35 in ULD was similar or even lower than that of healthy subjects. CONCLUSION: Enlarged but relatively stable SEP amplitudes had a consistency with so-called self-limited clinical course in Japanese ULD. SEP amplitude could be one of the surrogate markers of the degree of cortical hyperexcitability in ULD during the long-term follow-up period.
PURPOSE: To delineate chronological changes of cortical hyperexcitability by long-term follow-up of the amplitudes of somatosensory evoked potentials (SEPs) in patients with Japanese Unverricht-Lundborg disease (ULD). METHOD: SEPs to median nerve stimulation were repeatedly examined in 7 genetically diagnosed ULDpatients with the mean interval of 11.9 years. The degree of temporal changes in the amplitude of 3 early cortical components, N20, P25 and N35, to the age was analyzed and compared with that of healthy subjects. RESULTS: Their clinical course was almost stable during the follow-up period, namely cessation of generalized tonic-clonic seizures and little or no progression of myoclonus. SEP amplitudes of P25 and N35 were enlarged in all patients and were gradually decreased with aging in ULD on average. The degree of temporal changes of P25 and N35 in ULD was similar or even lower than that of healthy subjects. CONCLUSION: Enlarged but relatively stable SEP amplitudes had a consistency with so-called self-limited clinical course in Japanese ULD. SEP amplitude could be one of the surrogate markers of the degree of cortical hyperexcitability in ULD during the long-term follow-up period.