Reference values for ultrasonograpy of peripheral nerves

Introduction: High-resolution ultrasonography (HRU) is a novel method that provides morphological information about peripheral nerves. We aimed to determine reference values for nerve cross-sectional area (CSA) on HRU. Methods: One hundred healthy volunteers had HRU of median, radial, ulnar, fibular, tibial, sural, and superficial fibular nerves at defined sites. The CSA was measured and the effects of age, gender, and body mass index (BMI) were evaluated. Results: CSA values in healthy subjects are described. CSA is larger in lower limb motor nerves than in sensory nerves at similar sites, and the CSA tends to be symmetrical. The strongest effect on CSA was for age, although gender and BMI had some effects. Conclusions: This study provides normative values for HRU, and it suggests that further research with age- and gender-specific distributions must be a key priority in the development of HRU for use as a diagnostic test for peripheral nerve diseases.