Electrophysiological Characteristics of Genetically Confirmed Charcot-Marie-Tooth 1A

J Korean Neurol Assoc > Volume 24(1); 2006 > Article

Journal of the Korean Neurological Association 2006;24(1): 51-57.

유전학적으로 진단된 Charcot-Marie-Tooth 1A 환자의 전기생리학적 특성

이미희, 선우일남 최병옥a 서범천 조정희 김승민

연세대학교 의과대학 신경과학교실, 이화여자대학교 의과대학 신경과학교실a

Electrophysiological Characteristics of Genetically Confirmed Charcot-Marie-Tooth 1A

Mi Hee Lee

Department of Neurology, Yonsei University College of Medicine, Seoul; Department of Neurology, Ewha Womans University College of Medicinea, Seoul, Korea

Abstract

Background: Charcot-Marie-Tooth (CMT) disease is pathologically divided into the following two types: demyelinating type and axonal type. This study aimed to analyze the results of the electrophysiological studies of CMT1A and to reevaluate the clinical significance of nerve conduction studies (NCS).
Methods: The subjects of the study were 18 patients with genetically confirmed CMT1A during the period of 1995. 1.-2004. 8. The NCS data from 22 family members of the patients were also included. The nerve conduction velocities, conduction blocks and compound muscle action potentials were analyzed.
Results: The subjects were composed of 19 males and 21 females. The mean NCV was 21.70 m/s in the median nerve, and the conduction block was observed in 13 patients (32.5%). The NCV was uniformly slow. The intrafamilial variation of NCVs between parents and their children were analyzed in 30 patients from 11 families. The mean velocity was 24.44±3.67 m/s in parents and 19.53±5.37m/s in their children.
Conclusions: The CMT1A showed the slowness in NCV, one of the characteristics of demyelinating neuropathy, and this slowing had a uniform pattern. Nerve conduction block was also frequently observed, the pattern of which was diffuse without dispersion, and non segmental. Because the NCV of the children tended to be slower than that of the parents, CMT1A may not be a simple progressive disease. The onset and progression of CMT1A may be determined by other genetic and environmental factors.