Pattern reversal visual evoked response in retinitis pigmentosa

Area of Science:

• Ophthalmology
• Neuroscience
• Visual Electrophysiology

Background:

• Retinitis pigmentosa (RP) is a group of inherited retinal diseases that cause progressive vision loss.
• Objective measures of visual function are crucial for monitoring disease progression and evaluating treatment efficacy in RP.
• Traditional electroretinograms (ERGs) may be unrecordable or subnormal in RP patients, necessitating alternative assessment methods.

Purpose of the Study:

• To determine if pattern reversal visual evoked response (PVER) can objectively assess visual function in patients with retinitis pigmentosa (RP).
• To compare PVER results with visual acuity (VA) and visual field (VF) measurements in RP patients.
• To evaluate the utility of PVER as a diagnostic tool for RP when other electrophysiological tests are limited.

Main Methods:

• Retrospective review of medical records of 29 RP patients with VA better than 20/100.
• Recording of steady-state PVER using five different check sizes (160 to 10 min of arc).
• Measurement of best-corrected VA (ETDRS chart) and visual fields (Goldmann perimetry, isopter IV-2).

Main Results:

• All RP patients had recordable PVERs, while only 41% had recordable ERGs.
• PVER amplitudes showed a significant correlation with VA at intermediate check sizes (40 and 20 min of arc).
• RP patients exhibited a flattened PVER amplitude-check size function compared to normal subjects, indicating reduced visual function.

Conclusions:

• PVER is a valuable and objective method for evaluating visual function in RP patients with preserved central vision.
• PVER can provide useful information when ERGs are subnormal or unobtainable in RP.
• The findings support the use of PVER as a complementary tool in the clinical management of retinitis pigmentosa.