Abstract
Purpose:
Retinitis pigmentosa (RP) encompasses a group of hereditary retinal diseases with progressive photoreceptor apoptosis. Ocular blood circulation has been shown to be altered in RP in several experimental and clinical studies. The aim of this study was to compare choroidal thickness (CT) profile in eyes of patients with RP using enhanced depth imaging (EDI) and spectral domain (SD) optical coherence tomography (OCT), with impaired healthy control, and to evaluate the relationship between choroidal thickness profile, sickness severity and visual acuity impairment
Methods:
A prospective, case-control study of 20 patients with RP imaged using the Spectralis EDI-OCT protocol (Heidelberg Engineering, Germany), 20 healthy subjects participated as control. Visual acuity was measured with ETDRS scale. CT measures of 40 eyes of 20 patients were compared point by point to CT of 40 eyes of 20 controls with similar refraction. Statistical analysis was performed to compare CT at each location between the two groups and to correlate CT with best-corrected visual acuity and age. MAIN OUTCOME: compare thickness profiles of the control and RP groups. SECOUNDARY OUTCOME: Association between CT, visual acuity and age were determined in RP group.
Results:
Mean ages were 50.35 years for RP patients and 50.65 years for control patients. Mean CT measurements were 222 ± 103 µm in RP patients and 319 ±86 µm in controls (p<0.0001). The thickness gradually decreased toward the peripheral retina in both group. CT was thinning significantly with age in control group (-4.5µm per 10 years), but it did not reach significance in the RP group. Patients with poorer visual acuity tended to have thinner choroids (- 4.5 µm by 10 letters in RP group). After adjusting with choroidal thinning related to age, CT was significantly related to visual loss with a reduction of 15µm by 10 letters loss in RP patients. DISCUSSION: To this day one publication has evaluated the choroid's changes in RP patients. Our study confirms this first result showing a choroidal thinning. However, we demonstrate the relationship between EC and visual acuity loss, regardless of the choroid thinning associated with age among patients with RP.
Conclusions:
We demonstrated thinning of the choroid in the RP patients compared to controls. This choroidal thinning could be a sign of the retinal disease severity in retinitis pigmentosa patients.
Keywords: 688 retina •
550 imaging/image analysis: clinical •
702 retinitis