Single-fiber conduction study of motor nerve in patients with diabetic peripheral neuropathy / 中华神经科杂志

ABSTRACT

Objective To assess the function of motor nerve fiber in patients with diabetic peripheral neuropathy (DPN) by single-fiber conduction studies.Methods According to the diagnostic standard of DPN issued in Toronto meeting in 2009,on the basis of the result of peroneal nerve conventional conduction study,a total of 65 patients with DPN in the Department of Endocrinology and the Department of Neurology of Tianjin Third Central Hospital from October 2012 to October 2013 were enrolled into the study,from whom 33 had abnormal sensory conduction (sensory-diabetic peripheral neuropathy group,S-DPN group),32 had abnormal sensory motor conduction (sensory motor-diabetic peripheral neuropathy group,SM-DPN group).Single-fiber conduction velocity (SF-CV) and single-fiber distal motor latency (SF-DML)were detected in all subjects.The obtained results were compared with the data from 34 healthy volunteers (control group).The relationship of SF-CV,SF-DML and the duration of diabetes mellitus,fasting glucose,HbA1 c was also studied in DPN patients.Results The SF-CV ((43.1 ± 3.6) m/s) was decreased in S-DPN group compared with control group ((47.5 ± 3.3) m/s,t =5.077,P ＜ 0.01).There were no significant differences in SF-DML ((3.6 ± 0.7) ms),motor nerve conduction velocity (MCV (49.5 ± 2.6)m/s) and DML ((3.4 ± 0.6) ms) in S-DPN group compared with that of control group ((3.4 ± 0.5) ms,(50.9 ± 3.5) m/s,(3.2 ± 0.5) ms,respectively).SM-DPN group had lower SF-CV ((35.2 ± 3.6)m/s,t =9.119,14.219),MCV ((40.9 ± 3.2) m/s,t =11.131,13.025) and increased SF-DML ((4.5±0.7) ms,t=5.692,7.231),DML ((4.2 ±0.7) ms,t=5.561,6.975) compared with the other two groups (P ＜0.01).SF-CV in DPN patients was negatively related to the diabetic duration (r =-0.340,P =0.006),while SF-DML had no correlation with duration of DM,fasting blood glucose and HbAlc.Conclusions Detection of SF-CV is easy to find early motor nerve dysfunction in DPN patients.SF-CV is decreased with the increasing duration of diabetes.