Visual acuity and perimacular retinal layers detected by optical coherence tomography in patients with retinitis pigmentosa

Background: The remaining retinal neurones or layered structure in the degenerating retina have been the prerequisite for epiretinal or subretinal retinal prostheses. Aim: To detect the layered structure in the eyes of patients with retinitis pigmentosa by optical coherence tomography. Methods: In a prospective non-comparative study, 115 eyes of 58 consecutive patients with retinitis pigmentosa underwent optical coherence tomography to obtain horizontal and vertical retinal cross-section images at the centre of the macula. The number of high-reflectance retinal layers, one, two or three layers, was tested to determine whether it correlates with best-corrected visual acuity. Results: The best-corrected visual acuity was significantly better in the eyes in which more retinal layers were detected (p<0.001, Kruskal-Wallis test, p<0.05, Tukey-Kramer test). The best-corrected visual acuity in the right eye and in the left eye was correlated with each other (p<0.001, Spearman rank correlation test) and decreased with age. Conclusions: Optical coherence tomography can be used to obtain information regarding the retinal layer structure in patients with retinitis pigmentosa, and may be used as a clinical test to assess the feasibility of retinal prostheses in future.