Influence of Demographic Factors on Nerve Ultrasound of Healthy Participants in a Multiethnic Asian Population

Background: High-resolution nerve ultrasound provides morphological information of peripheral nerves. We aimed to determine the normal ultrasonographic reference values of nerve cross-sectional area (CSA) in multiethnic Malaysian healthy participants.

Methods: Nerve ultrasound of the median, ulnar, radial, tibial, fibular, and sural nerves was performed in 84 healthy participants at anatomical-defined locations. The CSA at each scanned site was measured by tracing circumferentially inside the hyperechoic rim of each nerve. Comparisons were made between genders and ethnic groups. Correlations with age, ethnicity, gender, height, weight, and body mass index (BMI) were evaluated.

Results: CSA values and reference ranges in healthy participants were generated. Nerve CSA was significantly different in different gender (P = 0.002-0.032) and ethnic groups (P = 0.006-0.038). Men had larger nerve CSA than women, and Malay participants had larger nerve CSA compared to other ethnic groups. Nerve CSA had significant correlations to age, height, weight, and BMI (r = 0.220-0.349, P = 0.001-0.045).

Conclusion: This study provides normative values for CSA of peripheral nerves in a multiethnic Malaysian population, which serves as reference values in the evaluation of peripheral nerve disorders. The ethnic differences in nerve CSA values should be considered during nerve ultrasound.