Importance of Nerve Ultrasound Reference Data in Hereditary Neuropathies

Establishing normal values for nerve ultrasound may assist in the diagnosis and evaluation of children and adolescents with neuropathic disorders, according to study results published in Frontiers in Neurology.

As nerve imaging are becoming an important tool to assess nerve morphology, establishing normal reference data is important. The goal of the current study was to compare nerve values in healthy children and adolescents with the values in those with neuropathies.

The study included 117 healthy participants aged between 8 and 17 years, as well as 25 children and adolescents of the same age range with a known history of acquired or inherited polyneuropathy.  High-resolution nerve ultrasounds were carried out using the same device in all study participants, including examination of arm and leg nerves. Cross-sectional area (CSA) was measured in all nerves, except for roots.

There was a significant correlation between nerve CSA with age in all measured segments and nerve growth achieved adult values at the age of 15. While in the median nerve and the proximal tibial nerve CSA values were higher among boys, no difference was found elsewhere. There was a significant correlation between body mass index and CSA only in the distal median nerve segments.

The percentile curves of the nerves were calculated by the LMS method and the researchers were able to define the percentile values for each age and each nerve segment.

In all children and adolescents with known hereditary neuropathies with demyelination there was evidence for enlarged nerves on the imaging study in most segments, compared with the age-matched control group. In addition, demyelinating neuropathies, including lysosomal storage disease, revealed multifocal nerve enlargement and inflammatory neuropathies revealed multifocal proximal predominant nerve enlargement.

“These reference values simplify the analysis of children and adolescents with neuropathic disorders and clarify underlying diagnoses in many cases. These data enable initiations of nerve imaging studies in distinct pediatric neuromuscular disorders,” concluded the researchers.

Reference

Grimm AS, Schubert C, Grimm A, et al. Normative observational nerve ultrasound values in school-age children and adolescents and their application to hereditary neuropathies. Front Neurol. 2020;11:303. doi:10.3389/fneur.2020.00303