正常人腕管内正中神经的超声解剖学研究及其意义

Ultrasonographic anatomy of median nerve in carpal tunnel of normal persons

目的探讨腕管内正中神经的超声解剖测量方法及各项指标,为临床提供正常解剖参数。方法应用高频超声检查60侧正常人腕管段正中神经,分别测量其腕管入口、中点和出口平面的横截面积,腕管中点平面正中神经的扁平率和屈肌支持带的厚度。应用超声剪切波弹性成像技术测量30侧腕管内正中神经近1/3段、中1/3段、远1/3段的硬度值。结果腕管入口、中点、出口平面正中神经截面积分别为(0.09±0.02)、(0.08±0.02)、(0.10±0.03)cm2,不同部位截面积均值无统计学差异(P<0.01);腕管中点平面正中神经的扁平率3.12±0.29;屈肌支持带厚度为(0.33±0.07)cm。正中神经腕管近段、中段、远段最高硬度的分别为(41.3±10.3)、(35.4±5.8)、(38.1±4.3)k Pa,不同部位硬度均值无统计学差异(P>0.05)。结论高频超声检查为临床提供了腕管内正中神经形态学解剖参数,剪切波弹性成像提供了神经硬度参数。两者结合应用为腕管综合征的临床诊断提供超声解剖学依据。

Objective To discuss measuring methods and indicators in ultrasonographic anatomy of the median nerve in carpal tunnel. Methods 60 sides media nerve in carpal tunnel of normal subjects underwent high-frequency ultrasonographic examination. Cross-sectional area of the median nerve at entrance plane, midpoint plane and exit plane were measured. thethickness of the palmar retinaculum, the flattening ratio of the median nerve at midpoint were measured too. The stiffness of median nerve in carpal tunnels of 30 sides was measured at the proximal 1/3 segment, middle 1/3 segment, and distal 1/3 segment by ultrasonic shear wave elastography. Results：The mean cross-sectional area of the median nerve at entrance plane, midpoint plane and exit plane respectively were（0.09±0.02）cm^2,（0.08±0.02）cm^2 and （0.10±0.03）cm^2; There was no statistical difference among the mean value. The mean flattening ratio of the median nerve at midpoint plane was 3.12±0.29. The mean thickness of palmar retinaculum was（0.33±0.07）cm. The mean value of maximum stiffness at the proximal segment, the middle segment, and the distal segment respectively were （41.3±10.3）kPa,（35.4±5.8）kPa and（38.1±4.3）kPa,there was no statistical difference among the mean value. Conclusion： High-frequency ultrasonographic examination may provide parameters of the median nerve in carpal tunnel, and shear wave elastography may provide stiffness parameter of the median nerve. Combined application of both examination may provide anatomical gist for clinical diagnosis of carpal tunnel syndrome.