Optical coherence tomography does not support optic nerve involvement in amyotrophic lateral sclerosis

In recent years a possible non-motor involvement of the nervous system in amyotrophic lateral sclerosis (ALS) has come into the focus of research and has been investigated by numerous techniques. Optical coherence tomography (OCT) - with its potential to reveal neuroaxonal retinal damage - may be an appropriate tool to investigate whether the anterior visual pathway is involved. Our aim was to determine whether OCT-based measures of retinal nerve fiber layer, ganglion cell layer, inner nuclear layer and outer nuclear layer thickness are abnormal in ALS, or correlated with disease severity.

Seventy-six ALS patients (144 eyes) and 54 healthy controls (108 eyes; HCs) were examined with OCT, including automated intraretinal macular segmentation. ALS disease severity was determined with the Amyotrophic Lateral Sclerosis Functional Rating Scale - Revised.

There was no significant difference between ALS patients and HCs in any of the examined OCT measures. Moreover, OCT parameters showed no correlation with clinical measures of disease severity.

These findings indicate that involvement of the anterior visual pathway is not one of the non-motor manifestations of ALS.