Importance of Sample Size for the Estimation of Repeater F Waves in Amyotrophic Lateral Sclerosis  

作　　者：Jia Fang Ming-Sheng Liu Yu-Zhou Guan Bo Cui Li-Ying Cui 

机构地区：[1]Department of Neurology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100730, China

出　　处：《Chinese Medical Journal》2015年第4期515-519,共5页中华医学杂志（英文版）

摘　　要：Background：In amyotrophic lateral sclerosis （ALS）,repeater F waves are increased.Accurate assessment of repeater F waves requires an adequate sample size.Methods：We studied the F waves of left ulnar nerves in ALS patients.Based on the presence or absence of pyramidal signs in the left upper limb,the ALS patients were divided into two groups：One group with pyramidal signs designated as P group and the other without pyramidal signs designated as NP group.The Index repeating neurons （RN） and Index repeater F waves （Freps） were compared among the P,NP and control groups following 20 and 100 stimuli respectively.For each group,the Index RN and Index Freps obtained from 20 and 100 stimuli were compared.Results：In the P group,the Index RN （P =0.004） and Index Freps （P =0.001） obtained from 100 stimuli were significantly higher than from 20 stimuli.For F waves obtained from 20 stimuli,no significant differences were identified between the P and NP groups for Index RN （P =0.052） and Index Freps （P =0.079）; The Index RN （P ＜ 0.001） and Index Freps （P ＜ 0.001） of the P group were significantly higher than the control group; The Index RN （P =0.002） of the NP group was significantly higher than the control group.For F waves obtained from 100 stimuli,the Index RN （P ＜ 0.001） and Index Freps （P ＜ 0.001） of the P group were significantly higher than the NP group; The Index RN （P ＜ 0.001） and Index Freps （P ＜ 0.001） of the P and NP groups were significantly higher than the control group.Conclusions：Increased repeater F waves reflect increased excitability of motor neuron pool and indicate upper motor neuron dysfunction in ALS.For an accurate evaluation of repeater F waves in ALS patients especially those with moderate to severe muscle atrophy,100 stimuli would be required.Background：In amyotrophic lateral sclerosis （ALS）,repeater F waves are increased.Accurate assessment of repeater F waves requires an adequate sample size.Methods：We studied the F waves of left ulnar nerves in ALS patients.Based on the presence or absence of pyramidal signs in the left upper limb,the ALS patients were divided into two groups：One group with pyramidal signs designated as P group and the other without pyramidal signs designated as NP group.The Index repeating neurons （RN） and Index repeater F waves （Freps） were compared among the P,NP and control groups following 20 and 100 stimuli respectively.For each group,the Index RN and Index Freps obtained from 20 and 100 stimuli were compared.Results：In the P group,the Index RN （P =0.004） and Index Freps （P =0.001） obtained from 100 stimuli were significantly higher than from 20 stimuli.For F waves obtained from 20 stimuli,no significant differences were identified between the P and NP groups for Index RN （P =0.052） and Index Freps （P =0.079）; The Index RN （P ＜ 0.001） and Index Freps （P ＜ 0.001） of the P group were significantly higher than the control group; The Index RN （P =0.002） of the NP group was significantly higher than the control group.For F waves obtained from 100 stimuli,the Index RN （P ＜ 0.001） and Index Freps （P ＜ 0.001） of the P group were significantly higher than the NP group; The Index RN （P ＜ 0.001） and Index Freps （P ＜ 0.001） of the P and NP groups were significantly higher than the control group.Conclusions：Increased repeater F waves reflect increased excitability of motor neuron pool and indicate upper motor neuron dysfunction in ALS.For an accurate evaluation of repeater F waves in ALS patients especially those with moderate to severe muscle atrophy,100 stimuli would be required.

关 键 词：Amyotrophic Lateral Sclerosis Repeater F waves Upper Motor Neuron 

分 类 号：S858[农业科学—临床兽医学] S858.287.7[农业科学—兽医学]