Multifocal VEP assessment of optic neuritis evolution

Daniah Alshowaeir; Con Yannikas; Raymond Garrick; Anneke Van Der Walt; Stuart L Graham; Clare Fraser; Alexander Klistorner

doi:10.1016/j.clinph.2014.11.010

Multifocal VEP assessment of optic neuritis evolution

Clin Neurophysiol. 2015 Aug;126(8):1617-23. doi: 10.1016/j.clinph.2014.11.010. Epub 2014 Nov 20.

Authors

Daniah Alshowaeir¹, Con Yannikas², Raymond Garrick³, Anneke Van Der Walt⁴, Stuart L Graham⁵, Clare Fraser⁶, Alexander Klistorner⁷

Affiliations

¹ Department of Ophthalmology, University of Sydney, Sydney, Australia; Department of Ophthalmology, King Saud University, Riyadh, Saudi Arabia. Electronic address: d_alshowair@hotmail.com.
² Concord Hospital, Sydney, Australia; Department of Neurology, Royal North Shore Hospital, Sydney, Australia.
³ Department of Neurology, St Vincent Hospital, Sydney, Australia.
⁴ Department of Neurology, Royal Melbourne Hospital, Melbourne, Australia.
⁵ Department of Ophthalmology, Macquarie University, Sydney, Australia.
⁶ Department of Ophthalmology, University of Sydney, Sydney, Australia.
⁷ Department of Ophthalmology, University of Sydney, Sydney, Australia; Australian School of Advanced Medicine, Macquarie University, Sydney, Australia.

PMID: 25481337
DOI: 10.1016/j.clinph.2014.11.010

Abstract

Objective: To evaluate multifocal visual evoked potentials (mfVEP) changes in optic neuritis (ON) and fellow eyes during first year after the attack.

Methods: Eighty-seven patients and twenty-five controls were examined. Patients were classified as multiple sclerosis (MS) group, high risk (HR) or low risk (LR) groups for conversion to MS. mfVEP recordings and retinal nerve fiber layer (RNFL) thickness were analyzed.

Results: Recovery of amplitude and shortening of latency was fastest within the first 3months. The largest amplitude reduction and longest latency delay of the ON eye were recorded in the MS group. This was accompanied by deterioration of both parameters in fellow eyes (p<0.03). mfVEP remained stable in fellow eyes of the LR group. Inter-eye asymmetry showed similar amount of amplitude reduction and latency delay in all three groups. RNFL thickness strongly correlated with mfVEP amplitude as early as 3 months after ON (R(2)=0.6, p=0.001).

Conclusion: mfVEP amplitude is an early predictor of post-ON axonal loss. The apparent more severe involvement of ON eyes in the MS subgroup may be due to subclinical inflammation along the visual pathway.

Significance: Severity of amplitude reduction and latency delay after episode of ON is not MS-related. Retro-chiasmal demyelination is a possible factor contributing to amplitude and latency differences between MS and non-MS patients.

Keywords: Axonal loss; Demyelination; Multiple sclerosis; Optic neuritis; mfVEP.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Adult
Axons / physiology
Demyelinating Diseases / physiopathology
Disease Progression
Evoked Potentials, Visual / physiology*
Female
Humans
Male
Middle Aged
Optic Neuritis / diagnosis*
Optic Neuritis / physiopathology
Visual Pathways / physiopathology*
Visual Perception / physiology*
Young Adult