Independent patterns of damage to retinocortical pathways in multiple sclerosis without a previous episode of optic neuritis

• Published in: Journal of neurology Vol. 258; no. 9; pp. 1695 - 1704
• Main Authors: Reis, Aldina, Mateus, Catarina, Macário, M. Carmo, de Abreu, José R. Faria, Castelo-Branco, Miguel
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer-Verlag 01.09.2011; Springer; Springer Nature B.V
• Subjects: Adult; Automation; Biological and medical sciences; Case-Control Studies; Comorbidity - trends; Disease; Disease Progression; Female; Humans; Male; Medical sciences; Medical screening; Medicine; Medicine & Public Health; Middle Aged; Multiple sclerosis; Multiple Sclerosis - complications; Multiple Sclerosis - epidemiology; Multiple Sclerosis - pathology; Multiple sclerosis and variants. Guillain barré syndrome and other inflammatory polyneuropathies. Leukoencephalitis; Neurology; Neuroradiology; Neurosciences; Optic Nerve - pathology; Optic Nerve - physiopathology; Optic Neuritis - complications; Optic Neuritis - diagnosis; Optic Neuritis - epidemiology; Original Communication; Pathophysiology; Retina - pathology; Retina - physiopathology; Retinal Ganglion Cells - pathology; Visual acuity; Visual impairment; Visual Pathways - pathology; Visual Pathways - physiopathology; Wallerian Degeneration - diagnosis; Wallerian Degeneration - etiology; Young Adult; Biomarkers; Multiple sclerosis; Visual function; Retinocortical pathways; Optic neuritis; Nervous system diseases; Optic nerve; Inflammatory disease; Eye disease; Cranial nerve disease; Visual pathway; Optic nevritis; Central nervous system disease
• ISSN: 0340-5354; 1432-1459
• DOI: 10.1007/s00415-011-6008-y

Asymptomatic visual loss is a feature of multiple sclerosis (MS) but its relative impact on distinct retinocortical pathways is still unclear. The goal of this work was to investigate patterns of subclinical visual impairment in patients with MS with and without clinically associated previous optic neuritis (ON). We have used functional methods that assess parvo-, konio- and magnocellular pathways in order to compare pathophysiological mechanisms of damage in a population of 44 subjects with MS (87 eyes), with and without a previous episode of ON. These methods included chromatic contrast sensitivity across multiple chromatic axes (Cambridge Colour Test–parvo/konio pathways), perimetric achromatic contrast sensitivity for the magno pathway [frequency doubling technique (FDT)] and pattern visual evoked potentials (VEP). These measures were correlated with field sensitivity measures obtained using conventional automated static perimetry (ASP) and were also compared with conventional clinical chromatic/achromatic contrast sensitivity chart-based measures. We have found evidence for uncorrelated damage of all retinocortical pathways only in patients with MS without ON. VEP evidence for axonal damage was found in this group supporting the emerging notion of axonal damage even in sub-clinical stages of ON/MS pathophysiology. Only in this group was significant correlation of functional measures with disease stage observed, suggesting that distinct pathophysiological milestones are present before and after ON has occurred.