Morphologic changes and visual outcomes in resolved central serous chorioretinopathy treated with ranibizumab

Abstract

Context: Central serous chorioretinopathy (CSC).

Objective: To evaluate the effect of intravitreal ranibizumab injection and the correlation between foveal morphologic changes and visual outcomes in patients with resolved CSC.

Materials and methods: We measured outer nuclear layer (ONL) thickness, outer layer (OL) thickness and evaluated the integrity of the photoreceptor inner-outer segment (IS/OS) junction, the status of the external limiting membrane (ELM) at the central fovea using spectral-domain optical coherence tomography (OCT) in 35 eyes of 35 patients with resolved CSC. The eyes were divided into two groups: The initial medical treatment administered to Group1 (n = 17) then received intravitreal ranibizumab injections, Group 2 (n = 18) received medical treatment. Group 3 was composed of normal eyes (n = 20, as a control). We also investigated a correlation between the ONL thickness and best corrected visual acuity (BCVA).

Results: The mean age was 45.7 ± 7.2 (ranged from 27 to 55 years). The mean follow-up period was 14.2 months (minimum 6, maximum 24 months). The mean ONL and OL thickness in Group 1 were significantly thinner than Group 3 (p < 0.005). The ONL thickness was correlated with the BCVA (r = 0.681, p = 0.001). Thirty-tree patients had improvement in BCVA after treatment. Discontinuity of the IS/OS junction was found in 15 eyes (88.2%) in Group 1, in 5 eyes (27.7%) in Group 2 and in no eyes in Group 3.

Discussion: We demonstrated that prolonged serous detachment results in photoreceptor cell loss (apoptosis) and thinning of the ONL. Thinning of the ONL correlates with poorer vision, which has been found by other investigators. Furthermore, vascular endothelial growth factor (VEGF) may be neuroprotective to the photoreceptors which might explain the additional thinning in the patients treated with ranibizumab. This raises the possibility that treatment with VEGF inhibitors may be unfavourable to patients with CSC, even though it speeds recovery and vision does improve.

Conclusion: Intravitreal ranibizumab injection leads to thinning of the ONL and the OL in patients with resolved CSC. The ONL thickness reduction and discontinuity of the IS/OS junction results in poor visual prognosis in resolved CSC eyes.

Keywords: Central serous chorioretinopathy; external limiting membrane; inner outer segment; outer layer; outer nuclear layer; pectral-domain optical coherence tomography; ranibizumab; retinal layers.