CHOROIDAL STRUCTURE ALTERED BY DEGENERATION OF RETINA IN EYES WITH RETINITIS PIGMENTOSA.

PURPOSE: To compare the structural characteristics of the choroid in the areas with greater retinal degeneration to the areas with less retinal degeneration in eyes with retinitis pigmentosa (RP). METHODS: Patients with RP who had a hyperautofluorescent ring were studied. The choroidal images obtained by enhanced depth imaging optical coherence tomography located 7,500 µm from the optic disk in the horizontal plane were analyzed. The cross-sectional areas of the total, luminal, and stromal choroid were measured. The area within the hyperautofluorescent ring was defined as the "central choroid" with less retinal degeneration. RESULTS: Thirty-seven eyes of 24 patients with RP were studied. The cross-sectional area of the total choroid was significantly smaller in the RP eyes than that in the control eyes (P < 0.01). The stromal areas of the choroid were not significantly different from the stromal areas of the controls. However, the luminal areas of the nasal and temporal choroid in the RP eyes were significantly smaller than that of the corresponding areas of the controls. The ratio of the luminal area to the total choroidal area in the central choroid was 68.0 ± 3.3% which was significantly larger than that of the nasal or the temporal choroid (P < 0.01). CONCLUSION: The choroidal structure is differentially altered in eyes with RP. The changes in the choroid were dependent on whether they were located within the hyperautofluorescent or outside the hyperautofluorescent ring.