Graded, histological evaluations on eyes from 82 patients with multiple sclerosis (MS) and 10 subjects with other neurological diseases, with immunohistochemistry on a subset, were performed and correlated with clinical and pathological findings in a study at University of California San Francisco, and Queen’s University and Health Trust, Belfast, N Ireland, UK. Ages of subjects ranged from 21 to 87 years; 76 had chronic MS (mean duration 23 +/- 13 years) and 6 had acute MS (mean duration 4 +/- 3 months). In 121 eyes from chronic cases, 13% of retinae showed periphlebitis and 80%, cell loss; 72% of optic nerves showed gliosis and 71%, atrophy; and 72% showed iris reaction. Except for retina periphlebitis, all other abnormalities were significantly more frequent in MS cases than in those with other neurological diseases, controlling for age and gender (P<0.001). Severity of retinal atrophy was correlated with overall brain weight (P=0.04). Atrophic changes were seen in the retinal nerve fiber layer, ganglion cell layer, and also in the inner nuclear layer, suggesting widespread damage. Prominent gliosis and inflammation surrounding vessels of the inner retina could impact reliability of optical coherence tomography evaluations. The injury to both iris and retina were seen at all stages of disease. The odds of finding retinal atrophy in subjects with MS was >17 times greater than in non-MS subjects. 
COMMENT. Retinal pathology and sheathing of retinal veins in MS were described by Rucker CW at the Mayo Clinic in 1944 and reviewed by him in 1972 (Mayo Clin Proc 1944;19:176-178) . Rucker’s expertise in neuro-ophthalmology sometimes diagnosed MS in unsuspected cases. Detailed examination of the retina may be under-utilized in clinical neurology. This description of ocular pathology at all disease stages in a large adult case series supports the utility of tracking MS disease progression by retinal examination and imaging in patients of all ages.