Abstract
Purpose: :
Multifocal visual evoked potential (mfVEP) recording has been applied to objectively evaluate visual function in different pathologies such as glaucoma, optic neuritis. Compared to standard visual field testing with static automated perimetry (SAP), mfVEP provides physiologic information measuring not only the amplitude, but also the latency of the VEP signal. It is an objective method relying only on patients’ visual fixation. We analysed a series of seven mfVEP recordings in a patient with unilateral compressive optic neuropathy over two years, before and after radiation treatment, to see if the changes in the mfVEP recordings correlated with the simultaneously recorded SAP findings.
Methods: :
Static automated perimetry (SAP) and mfVEP recordings were obtained at 7 visits of 1 patient with compressive optic neuropathy. Monocular mfVEPs were recorded from each eye using a pattern–reversal dart board array with recording electrodes placed at and 4 cm above the inion as well as two lateral locations. Interpolated visual fields, monocular and interocular amplitude analyses were performed and compared to 100 normal control subjects.
Results: :
The mean deviation of the SAP visual fields ranged from –6.83 to –22.52 dB. The number of sectors deviating from normal at a significance level of p<0.01 in the mfVEP plots correlated qualitatively with the number of sectors seen on the interpolated visual fields.. The changes seen on SAP correlated with the findings in the mfVEP plots.
Conclusions: :
MfVEP may offer an alternative objective tool to evaluate visual function in patients with compressive optic neuropathy..
Keywords: visual fields • neuro-ophthalmology: optic nerve • electrophysiology: clinical