Multifocal and pattern-reversal visual evoked potentials vs. automated perimetry frequency-doubling technology matrix in optic neuritis

Abstract

Background:To compare the usefulness of the traditional pattern-reversal Visual Evoked Potentials (VEP) with multifocal VEP (mfVEP) and Frequency-Doubling Technology (FDT) perimetry in the evaluation of the ocular abnormalities induced by acute or subacute optic neuritis (ON).Materials and Methods:The test results of 24 ON patients were compared with those obtained in 40 normal control subjects. MfVEP recordings were obtained by using an Optoelectronic Stimulator that extracts topographic VEP using a pseudorandom m-sequence stimulus. Receiver operator characteristic (ROC) curves were calculated to determine the sensitivity and specificity of abnormal values.Results:The frequency of the abnormal ocular findings differed in the ON patients according to the used technique. Reduced visual sensitivity was demonstrated in 12 eyes (54.5%) using FDT perimetry; 17 eyes (77.2%) showed decreased amplitude and/or an increase in the implicit time of the P1 wave in mfVEP and 20 eyes (90.9%) showed an abnormal decrease in the amplitude and/or an increase in the latency of the P100 peak at VEP examination. The areas under the ROC curves ranged from 0.743 to 0.935, with VEP having the largest areas. The VEP and mfVEP amplitudes and latencies yielded the greatest sensitivity and specificity.Conclusions:The mfVEP and the FDT perimetry can be used for the evaluation and monitoring of visual impairment in patients with ON. The most sensitive and practical diagnostic tool in patients with ON is, however, the traditional VEP. The mfVEP can be utilized in those cases with doubtful or negative VEP results.

The electrophysiological assessment of visual function in Multiple Sclerosis

“…The advantage of recording independent VEPs from different parts of the visual field is that the electrical dipoles generated by the corresponding cortical regions do not cancel each other out ( Klistorner et al, 1998 ). Stimulating the visual field in such a fragmented fashion enhances the sensitivity to all regions evaluated and allows detection of smaller deficits, which may be missed by both the patient and by conventional VEPs ( Chan et al, 2005 , Nebbioso et al, 2013 ). The Phase 2 study of opicinumab (RENEW) study demonstrated mfVEPs superiority over conventional VEPs, by more readily detecting treatment-associated conduction changes in eyes recently affected by ON.…”

A new method for quantifying mfVEP signal intensity in multiple sclerosis

“…Using the PoE parameter, there was significant difference in 10 cases, however only 8 cases present significant difference using SNR parameter. Significant difference was reported previously between Control and MS ON eyes [24,41] and between Control and MS no ON eyes [24]. As in previous works [42] no significant difference was found between MS-on y MS-nON due to it could be stated that MS-nON are subclinically affected.…”

<p>Neurofibromatosis Type 1: Ocular Electrophysiological and Perimetric Anomalies</p>

“…The peripheral and intermediate fibers were explored through the p-PEVs at 120ʹ and 60′ (low and medium spatial frequencies), which in the control group reported higher conduction velocity values than those reported for central fibers, examined with the p-VEPs 15ʹ (high spatial frequencies), results congruous with existing literature. 24,25 In the NF1 group, the p-VEPs 120ʹ and 60ʹ showed a statistically significant increase in latency and a reduction in amplitude. These data may indicate the suffering of the outermost fibers of the visual pathways.…”