Cerebrospinal fluid neurofilament light chain levels predict visual outcome after optic neuritis.
Optic neuritis is a good model for multiple sclerosis relapse, but currently no tests can accurately predict visual outcome.
The purpose of this study was to examine whether cerebrospinal fluid (CSF) biomarkers of tissue damage and remodelling (neurofilament light chain (NF-L), myelin basic protein, osteopontin and chitinase-3-like-1) predict visual outcome after optic neuritis.
We included 47 patients with optic neuritis as a first demyelinating episode. Patients underwent visual tests, optical coherence tomography (OCT), magnetic resonance imaging (MRI) and lumbar puncture. Biomarkers were measured in CSF by enzyme-linked immunosorbent assay (ELISA). Patients were followed up six months after onset and this included visual tests and OCT. Outcome measures were inter-ocular differences in low contrast visual acuity (LCVA), retinal nerve fibre layer (RNFL) and ganglion cell layer+inner plexiform layer (GC-IPL) thicknesses.
CSF NF-L levels at onset predicted inter-ocular differences in follow-up LCVA (β=13.8, p=0.0008), RNFL (β=5.6, p=0.0004) and GC-IPL (β=4.0, p=0.0008). The acute-phase GC-IPL thickness also predicted follow-up LCVA (β=12.9, p=0.0021 for NF-L, β=-1.1, p=0.0150 for GC-IPL). Complete/incomplete remission was determined based on LCVA from 30 healthy controls. NF-L had a positive predictive value of 91% and an area under the curve (AUC) of 0.79 for incomplete remission.
CSF NF-L is a promising biomarker of visual outcome after optic neuritis. This could aid neuroprotective/regenerative medical advancements.
Figure: Associations between baseline cerebrospinal fluid (CSF) neurofilament light chain (NF-L) levels and visual outcome parameters after optic neuritis (ON).Associations between CSF NF-L levels measured in the acute phase of optic neuritis and inter-ocular differences in visual outcome measures: (a) low contrast visual acuity (LCVA) function (b) retinal nerve fibre layer (RNFL) thickness and (c) ganglion cell layer+inner plexiform layer (GC-IPL) thickness. A high value on the y-axis thus indicates a poor clinical outcome and high degree of neuronal loss. Correlation coefficients (r=Spearman’s rho) and p-values as calculated by Spearman’s rank correlation analysis are given at the top of each panel.