Tracking changes over time in retinal nerve fiber layer and ganglion cell-inner plexiform layer thickness in multiple sclerosis

Abstract

Background Neurodegeneration plays an important role in permanent disability in multiple sclerosis (MS). Objective To determine whether progressive neurodegeneration occurs in MS eyes without clinically-evident inflammation. Methods Retinal nerve fiver layer thickness (RNFLT) and ganglion cell-inner plexiform layer thickness (GCIPT) were measured using Cirrus optical coherence tomography (OCT) in 133 relapsing-remitting MS (RRMS) patients (149 no-ON, 97 ON eyes, last optic neuritis (ON) ≥6 months). 93 patients were scanned at two visits. Percents of abnormal GCIPT vs RNFLT (<5% of machine norms) in cross-sectional data were compared. Relations between RNFLT/GCIPT and MS duration (cross-sectional) and follow-up time (longitudinal) were assessed. Results GCIPT was abnormal in more eyes than RNFLT (27% vs 16% p=0.004 in no-ON, 82% vs 72% p=0.007 in ON). RNFLT and GCIPT decreased with MS duration by −0.49 µm/yr (p=0.0001) and −0.36 (p=0.005) for no-ON; −0.52 (p=0.003) and −0.41 (p=0.007) for ON. RNFLT and GCIPT decreased with follow-up time by −1.49 µm/yr (p<0.0001) and −0.53 (p=0.004) for no-ON, −1.27 (p=0.002) and −0.49 (p=0.04) for ON. Conclusions In RRMS eyes without clinically-evident inflammation, progressive loss of RNFLT and GCIPT occurred, supporting the need for neuroprotection in addition to suppression of auto-immune responses and inflammation.

OCT measurements of optic nerve head changes in idiopathic intracranial hypertension

“…Reduced RNFL and GCL thicknesses are established abnormalities in multiple sclerosis (MS) [17]. But GCL thickness appears to correlate better than RNFL thickness with visual function [18] and is, at least in part, superior over RNFL thickness measurements regarding reproducibility in MS [18,19]. In contrast to MS, more eyes showed normal GCL than normal RNFL in IIH [14].…”

Nonglaucomatous Localized Retinal Nerve Fiber Layer Defects in Behçet Uveitis

“…However, there might be undetectable subclinical episodes of optic neuritis and/or chronic low-level inflammation in the optic nerve even if the patients do not experience any episode of symptomatic optic neuritis. 23 Axonal loss is a prominent feature of MS and transection of axons in MS lesions has been demonstrated in several studies. 14,24-26 A descending degeneration of the axons is thought to result in atrophy of the RNFL and ganglion cells of the retina, which is typically demonstrated as diffuse RNFL thinning, but not localized defects on OCT images.…”

Clinical trials in progressive multiple sclerosis: lessons learned and future perspectives

“…136 Progressive thinning of the RNFL has been observed despite lack of inflammatory episodes, making this measure a compelling model for neurodegeneration. 137 …”