Electrophysiology testing in ophthalmology measures electrical responses from the retina, optic nerve, and visual pathways to assess their function. It includes tests such as electroretinography, visual evoked potentials, and electro-oculography.
Principles
Light or pattern stimuli are presented while electrodes record resulting electrical signals. The shape, amplitude, and timing of these responses reflect the integrity of specific retinal cells or visual pathway segments.
- Objective tests that do not rely on subjective visual reporting
- Protocols follow international standards for stimulus and recording conditions
- Results are compared with age-matched normative data
- Different tests target rods, cones, macula, or optic nerve selectively
Clinical Uses
Electrophysiology helps diagnose inherited retinal dystrophies, toxic retinopathies, optic neuropathies, and unexplained visual loss. It can distinguish retinal from post-retinal causes of reduced vision.
- Supports prognostic counselling in progressive conditions
- Monitors function in drug surveillance programmes
- Valuable when examination and imaging findings are inconclusive
- Interpretation requires specialist training and correlation with clinical findings
