计算机辅助对冲技术测定运动神经纤维传导速度分布的研究

Distribution of motor nerve conduction velocity detected with a new computer-assisted collision technique

目的:研究计算机辅助对冲技术的主要影响因素及运动纤维传导速度分布的正常值。方法:选择2004-05/2005-03知情同意的健康志愿者29人进行计算机辅助对冲技术检测,测定了正中、尺及腓总神经传导速度分布正常值范围,并对最慢纤维传导速度(慢纤维速度)的影响因素进行回归分析。观察了2名健康人不同肢体皮温(变化范围2～4℃)的传导速度分布结果和10名健康人的不同计算机辅助对冲技术刺激强度(最大、最大+15%～50%)传导速度分布的变化。对5名健康人的相同神经采用相同的计算机辅助对冲技术参数和方法分别进行3次重复检测,观察其结果的一致性和可重复性。结果:①室温20～22℃,肢体皮温(31.9±0.89)℃情况下,测得传导速度分布正常值,正中神经最慢速度(慢纤维速度CV10%)(47.31±4.58)m/s、中等速度(中速纤维速度CV50%)(52.17±3.78)m/s、最快速度(快纤维速度CV90%)(56.14±5.13)m/s;尺神经慢纤维速度(48.46±6.0)m/s、中速纤维速度(53.11±5.16)m/s、快纤维速度(57.33±5.04)m/s;腓总神经慢纤维速度(35.58±5.98)m/s、中速纤维速度(41.61±4.76)m/s、快纤维速度(46.04±3.50)m/s。②回归分析显示:身高、皮温和年龄与慢纤维速度呈负相关,身高是慢纤维速度最显著的影响因素(P=0.013)。③肢体皮温下降2℃时的传导速度分布结果与标准皮温比较无明显变化,下降4℃的传导速度分布数值明显降低,快纤维速度降低7～10m/s,慢纤维速度降低3～9m/s。④最大刺激强度和超强刺激(最大刺激量+15%～50%)的传导速度分布结果比较显示<50m/s的纤维分布明显减少,而快纤维速度无明显差别;超强刺激强度变化对传导速度分布结果无明显影响(P=0.999)。⑤计算机辅助对冲技术重复实验传导速度分布结果显示各组之间无显著差异(P正中=0.649,P腓总=0.984)。结论:计算机辅助对冲技术对研究不同传导速度的运动神经纤维具有重复性好、无创和敏感性高的特点,能更全面评价运动神经传导特性。因此计算机辅助对冲技术可能在周围神经病变的早期诊断,尤其是发现亚临床病变具有重要临床意义。

AIM： To investigate the main influencing factors for a new computerassisted collision technique （CCT） and the normal value of motor nerve conduction velocity distribution （CVD）. METHODS： Between May 2004 and March 2005, 29 healthy volunteers were detected with CCT, the normal ranges of CVD for the median, ulnar and peroneal nerves were determined, the influencing factors of the slowest fibrous conduction velocity were analyzed regressively. The results of conduction velocity distribution of different limbs＇ skin temperature （2-4 ℃） in 2 healthy subjects and the changes of conduction velocity distribution under different stimulus intensity of CCT （maximal stimulus intensity, maximal stimulus intensity±15% to 50%） in 10 healthy subjects were observed. The same nerves of 5 healthy subjects were repeatedly determined with the same CCT indexes and methods for 3 times, and concordance and reliability of the results were observed. RESULTS： ①Under the room temperature of 20-22 ℃and limbs＇ skin temperature of （31.9±0.89） ℃, the normal values of CVD were detected, the slowest velocity （CV10%） of median nerve was （47.31±4.58） m/s, middle velocity （CV50%） was （52.17±3.78） m/s and the fastest velocity （CV90%） was （56.14±5.13） m/s; The CV10%, CV50% and CV90% of ulnar nerve were （48.46±6.0） m/s, （53.11±5.16）m/s and （57.33±5.04） m/s; The CV10%, CV50% and CV90% of common peroneal nerve were （35.58±5.98） m/s, （41.61±4.76） m/s and （46.04±3.50） m/s. ② The regression analysis showed that body height, skin temperature and age had negative correlation with CV10%, and body height was the most significant influencing factor （P=0.013）. ③ When the limb temperature descended by 2 ℃, the CVD results had in obviously changes as compared with standard skin temperature,and the CVD value of 4 ℃ decrease was obviously reduced, the CV90% was reduced by 7-10 m/s, and CV10% was decreased by 3-9 m/s. ④ The comparison of CVD results of the maximal stimulus intensity and supramaximal stimulus intensity （maximal stimulus intensity±15% to 50%） indicated that the 〈 50 m/s fibrous distribution was obviously decreased, but CV90% had no obvious difference. The changes of supramaximal stimulus intensity also had no obvious influence on the CVD results （P=0.999）. ⑤ The CVD results in the CCT repetitive experiment showed that there were no significant differences among the groups （Pmedian merve= 0.649, Pcommen peroneal nerve = 0.984） CONCLUSION： CCT shows the higher sensitivity, good reproducibility, no traumatism and saving time. It is very important to evaluate the motor nerve function of different conduction velocities. Thus CCT can be used to diagnose the peripheral neuropathy, especially sub-clinical disorders.