Thickness of photoreceptor layers in polypoidal choroidal vasculopathy and central serous chorioretinopathy

To evaluate retinal thickness using spectral-domain optical coherence tomography (SD-OCT) with reduced speckle noise in eyes with polypoidal choroidal vasculopathy (PCV) compared to those with normal eyes and those with central serous chorioretinopathy (CSC).

We retrospectively reviewed cases of foveal serous retinal detachment in 36 eyes of 36 patients with active CSC and 23 eyes of 23 patients with active PCV, and 44 eyes of 44 normal subjects. Patients were examined using SD-OCT with reduced speckle noise, and the thickness of the outer nuclear layer (ONL), photoreceptor inner segment (IS), and photoreceptor outer segment (OS) were measured.

The ONL and IS were thicker in normal eyes than in eyes with CSC or PCV (P < 0.001). The OS was significantly less thick in eyes with PCV than in normal eyes (P < 0.001), whereas there was no significant difference between eyes with CSC and normal eyes. The thickness of IS and OS in eyes with PCV was related to fibrin or hemorrhage being present in the subretinal space. In eyes with PCV, best-corrected visual acuity at baseline correlated with IS thickness (P = 0.023).

Thinning of each photoreceptor layer was observed in the eyes of PCV patients as compared to that observed in the case of normal individuals. The differentiating factors between PCV and CSC, observed using SD-OCT, include the thinning of the OS in eyes with PCV, which makes SD-OCT helpful in differentiating PCV from CSC. More severe photoreceptor alterations were seen in PCV, because fibrin and hemorrhage were present in the subretinal space, which correlated with poorer vision.