Choroidal thickness in retinitis pigmentosa using EDI OCT

Abstract

AbstractPurpose To describe the choroidal thickness of patients with RP using enhanced depth imaging (EDI) and spectral domain (SD) optical coherence tomography (OCT), comparing with impaired non affected subjects.Methods Prospective, case‐control study of 20 patients with RP imaged using the Spectralis EDI protocol. 40 healthy age‐matched subjects participated in the study as control. RP patients had mild to severe disease, with a visual acuity range of ETDRS 20/20 to light perception. Choroidal thickness measures were determined via manual segmentation of the OCT image. Submacular choroidal thickness measurements were obtained beneath the fovea and at 500 µm intervals for 2.0 mm nasal and temporal to the centre of the fovea. These measurements on RP patients were compared to choroidal thickness measurements from 40 controls with similar refraction and no clinical evidence of retinal or glaucomatous disease. Statistical analysis was performed to compare choroidal thickness at each location between the two groups and to correlate choroidal thickness with best‐corrected visual acuity.Results Mean ages were 47.025 years for control patients and 49.3 years for RP patients (p>0.05). Mean choroidal thickness measurements were 211.9 ± 80 µm in RP patients and 305.6 ± 89 µm in controls (p<0.0001). The thickness gradually decreased toward the peripheral retina in the RP and control patients. It was greater in the temporal field than the nasal one in both groups. All values were highly significantly lower in RP group than those of the controls (p≤0.001). Patients with poorer visual acuity or older (longer duration of disease) tended to have thinner choroidsConclusion Submacular choroidal thickness, as measured by SD–OCT EDI, is significantly reduced in patients comparing with age matched cIontrol