Choroidal thickness map variations in patients with retinitis pigmentosa using enhanced depth imaging optical coherence tomography

Abstract

Objective The aim was to investigate changes in retinal and choroidal thickness (CT) maps in patients with retinitis pigmentosa (RP) in comparison to controls using enhanced depth imaging optical coherence tomography (OCT). Participants and methods A cross-sectional study was done on a consecutive sample of 32 eyes of 22 patients with RP. Control group included 30 eyes of 15 age-matched healthy participants. Full ophthalmological examination was done for every participant. Enhanced depth imaging OCT was performed measuring retinal and CT at the nine early treatment diabetic retinopathy study (ETDRS) subfields. Results The mean central CT was statistically significantly thinner (269.73±48.48 µm) in the patients’ group compared with 291.90±29.33 µm in the control group (P=0.023). On comparing the four choroidal quadrants between the two groups, patients with RP had significantly thinner choroid only in the nasal quadrant (P<0.001). The mean central macular thickness was statistically significantly thinner (226.45±61.35 µm) in the RP group than in controls (247.80±33.74 µm; P=0.009). The four macular quadrants were also significantly thinner in the RP group (P<0.001). Significant positive correlation was found between central macular thickness and central CT (r=0.511, P=0.003) and also at the upper and nasal quadrants (P=0.011 and <0.000,‏ ‏respectively). Conclusion Our study demonstrated that CT is thinned significantly in patients with RP in the central 1 mm and in the nasal quadrant. Evaluation of choroidal vasculature in future studies using OCT angiography may provide further insight into the involvement of choroid in the pathogenesis of RP