Textural markers of ultrasonographic nerve alterations in amyotrophic lateral sclerosis

Ultrasound has revealed cross-sectional nerve area (CSA) reduction in amyotrophic lateral sclerosis (ALS), but little is known about the sonographic nerve texture beyond CSA alterations. In a large cohort of 177 ALS patients and 57 control subjects, we investigated the covariance and disease-specific signature of several sonographic texture features of the median and ulnar nerves and their relationship to the patients' clinical characteristics. ALS patients showed atrophic nerves, a loss of the intranerve structures' echoic contrast, elevated coarseness, and a trend toward lower cluster shading compared with controls. A reduction in intranerve echoic contrast was related to longer disease duration and poorer functional status in ALS. Sonographic texture markers point toward a significant reorganization of the deep nerve microstructure in ALS. Future studies will be needed to further substantiate the markers' potential to assess peripheral nerve alterations in ALS.