Kobayashi K, Inagaki M, Sasaki M, Sugai K, Ohta S, Hashimoto T
Department of Child Neurology, National Center Hospital for Mental, Nervous and Muscular Disorders, NCNP, Tokyo, Japan.
Electroencephalogr Clin Neurophysiol. 1998 Oct;107(4):258-62. doi: 10.1016/s0013-4694(98)00069-8.
To review the EEG features of ring 20 syndrome in two patients and determine the characteristic pattern of this syndrome. The features of our cases and 24 patients reported in the literature will be discussed.
Report of two patients and review of literature.
The two patients had intractable epilepsy since childhood. Their clinical seizures were mostly complex partial seizures. Often the patients seizures were of prolonged duration. Ictal EEG revealed characteristic slow waves, and sharp waves. The slow waves were (1) usually synchronous high-voltage slow waves with or without a spike component predominantly in the frontal and frontopolar areas, (2) sometimes showed a change in frequency every several seconds, (3) continued for a long period, and (4) easily spread diffusely. The sharp waves were 5-6 Hz irregular and diffuse discontinuous sharp waves, and sometimes appeared predominantly in the centroparietal area. The clinical seizure pattern and EEG findings were similar in the 24 published cases.
These EEG findings may be a characteristic feature of ring 20 syndrome and thus may be useful as a diagnostic clue.
回顾两例环形20综合征患者的脑电图特征，并确定该综合征的特征性模式。将讨论我们病例的特征以及文献报道的24例患者的情况。
两例患者的报告及文献复习。
这两名患者自幼患有难治性癫痫。他们的临床发作大多为复杂部分性发作。患者发作常常持续时间较长。发作期脑电图显示特征性慢波和棘波。慢波为：（1）通常为同步性高电压慢波，有或无棘波成分，主要位于额叶和额极区；（2）有时每隔几秒频率会发生变化；（3）持续很长时间；（4）容易广泛扩散。棘波为5 - 6Hz不规则、弥漫性不连续棘波，有时主要出现在中央顶叶区。24例已发表病例的临床发作模式和脑电图表现相似。
这些脑电图表现可能是环形20综合征的特征性表现，因此可作为诊断线索。
