Purpose: Macular involvement in optic neuritis (ON) is well-recognised but poorly understood and may be of clinical relevance. This study explores macular structure-function correlates in acute ON.
Methods:This cross-sectional cohort study recruited ON patients within 14 days of symptom onset. Subjects underwent pattern electroretinography (PERG), pattern visual evoked potentials (PVEP) and optical coherence tomography (OCT) imaging. PERG P50 and N95 components were correlated with OCT data.Results: Twenty-six ON patients were recruited, comprising eleven multiple sclerosis (MSON), six myelin oligodendrocyte glycoprotein associated (MOGON) and nine isolated ON cases.These were compared with 28 healthy controls. PVEPs were undetectable in 11 (42%) of ON cases. When detectable, PVEP P100 was delayed (median 136ms range 110-173ms) and amplitude reduced (median 6μV, range 3-14μV) in ON compared with controls (both p<0.001). PERG P50 component amplitudes, largely reflecting macular function, were reduced in affected eyes (median 2.3μV; range 0.8-5.0μV) compared with controls (3.3μV; range 2.8-5.7μV) and compared with fellow eyes (p<0.001). There was often associated reduction in N95 but the N95:P50 ratio was below the reference range in the affected eyes of five patients.Eight cases (32%) had subnormal P50 amplitudes (<2.0μV) and these patients had poorer visual acuity (p=0.020). P50 amplitudes were positively correlated with inner nuclear layer thickness (rs=0.36; p=0.009) and macular ganglion cell and inner plexiform layer (mGCIPL) thickness (rs=0.44, p=0.022).
Conclusion: PERG P50 component reduction reveals dysfunction of inner macular layers inacute ON and correlates with structural alterations on OCT. These early macular pathologic processes are likely to contribute to the visual loss.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.