2. Visual evoked potentials in the diagnosis of multiple sclerosis

• Published in: Clinical neurophysiology Vol. 126; no. 3; pp. e29 - e30
• Main Author: Otruba, Pavel
• Format: Journal Article
• Language: English
• Published: Elsevier Ireland Ltd 01-03-2015
• Subjects: Neurology
• ISSN: 1388-2457; 1872-8952
• DOI: 10.1016/j.clinph.2014.10.161

Demyelination of optic nerve fibres causing deficit of visual acuity is often the first clinical manifestation of multiple sclerosis. Patients are indicated for visual evoked potential (VEP) examination to confirm slowing of conduction velocity in the optic nerve. A typical finding during VEP examination and full-field visual stimulation is prolongation of P100 wave latency with relatively preserved shape of the N–P–N complex and normal amplitude. The most sensitive parameter is the side-to-side difference in P100 latency. In some cases, response amplitude is reduced as well and the N–P–N complex is more poorly reproduced but the P100 latency prolongation is present in all cases. Sensitivity to detect demyelination damage in optic nerve fibres is very high, between 90% and 100% in the literature. The VEP examination assists in detecting pathology even when the neuro-ophthalmology examination is normal. Past retrobulbar neuritis may be detected by VEP even after recovery. VEP examination, thanks to its high sensitivity, has a fundamental position in the differential diagnosis of disorders of visual acuity and in diagnosis of demyelination damage to the optic nerve as clinically isolated deficit in the form of retrobulbar neuritis. Correct and early indication of the VEP examination plays an important role in the initiation of proper treatment and lowering the risk of irreversible consequences.