Electrode position and the multi-focal visual-evoked potential: role in objective visual field assessment

Aust N Z J Ophthalmol. 1998 May:26 Suppl 1:S91-4. doi: 10.1111/j.1442-9071.1998.tb01386.x.

Abstract

Purpose/methods: To improve the performance of visual-evoked potentials (VEP) in the assessment of the human visual field, the multi-focal cortically scaled pattern VEP was recorded up to 250 of eccentricity in normal subjects. Monopolar and varying bipolar electrode positions were used.

Results: The monopolar response was strongly biased towards the lower hemifield. Bipolar leads straddling the inion (2 cm above and below) achieved approximately equal signals from the upper and lower visual field. Division into sectors of similar wave-form augments the analysis compared with summed full-field responses.

Conclusion: With this technique, the multi-focal VEP can be used to objectively assess the visual field.

MeSH terms

  • Cerebral Cortex / anatomy & histology
  • Electrodes*
  • Evoked Potentials, Visual / physiology*
  • Humans
  • Ophthalmology / methods
  • Visual Fields / physiology*