Cone dysfunctions in retinitis pigmentosa with retinal nerve fiber layer thickening

Abstract

Purpose

To investigate whether or not thicker retinal nerve fiber layer (RNFL) in retinitis pigmentosa (RP) patients relates to functional abnormalities of the photoreceptors.

Methods

Optical coherence tomography-based RNFL thickness was measured by Stratus-3™ (Zeiss, Basel, Switzerland) optical coherence tomography and electroretinogram (ERG) recordings made using the RETI-port^® system (Roland, Wiesbaden, Germany) in 27 patients with retinitis pigmentosa and in 30 healthy subjects.

Results

Photopic ERG b-wave amplitude, cone ERG b-wave latency, 30 Hz flicker amplitude, and 30 Hz flicker latency had significant correlations to the RNFL-temporal (r = −0.55, P = 0.004, r = 0.68, P = 0.001, r = −0.65, P = 0.001, and r = −0.52, P = 0.007, respectively). Eyes with thicker RNFL (ten eyes) differed significantly from those with thinner RNFL (eight eyes) regarding cone ERG b-wave latency values only (P = 0.001).

Conclusion

Thicker RNFL in patients with retinitis pigmentosa may be associated with functional abnormality of the cone system.

Keywords:

• optical coherence tomography
• electroretinography
• photoreceptor
• b-wave

Disclosure

The authors have no competing/conflicts of interest, and no financial or proprietary interest in this study.