Nerve cross‐sectional area from childhood to old age: A high‐resolution nerve ultrasound study

Abstract

Background and purposeNerve cross‐sectional area (CSA) is not constant over the human lifespan. The relationship between an increasing CSA and age has been described as a linear positive correlation, but few studies have found a linear decrease in nerve size with older age. The aim of the present study was to analyze the development of nerve CSA in a healthy population from early childhood to old age using high‐resolution ultrasound.MethodsThe median, ulnar, radial and sural nerves were examined bilaterally at 18 nerve sites in 110 healthy children, adolescents and adults aged between 2 and 98 years. The CSA of every nerve site was evaluated separately and in different age groups. The correlation of CSA with age, height and weight was analyzed in a linear, logarithmic and quadratic model and correlation coefficients were compared in a goodness‐of‐fit analysis. Models were then adjusted for weight and height.ResultsLinear CSA–age correlations showed the lowest correlation coefficients for all nerve sites. An inverted parabolic curve suggesting a quadratic correlation of CSA and age was the best‐fitting model. Weight and height had a higher predictive value than age in adjusted models.ConclusionsThere is an increase in nerve size during childhood and adolescence and a trend towards a decrease in old age, suggesting an inverted parabolic curve partly explained by age‐related changes in weight and height. Enlarged nerves in elderly individuals should not be attributed to age alone.