Ranibizumab Versus Low-fluence Photodynamic Therapy in the Treatment of Chronic Central Serous Chorioretinopathy

Prospective Study on the Efficacy and Safety of Intravitreal Ranibizumab Versus Low-fluence Photodynamic Therapy in the Treatment of Chronic Central Serous Chorioretinopathy

The purpose of this study is to compare the efficacy and safety of intravitreal ranibizumab injection versus low-fluence PDT in the treatment of chronic CSC.

Central serous chorioretinopathy (CSC) is characterized by serous detachment of the neurosensory retina. The pathophysiology of CSC is not certain and various theories are proposed including impaired function of retinal pigment epithelium (RPE), choroidal ischemia and choroidal hyperpermeability leading to RPE damage. Acute CSC with monofocal or paucifocal changes of RPE usually shows spontaneous resolution and has a favorable visual outcome. Chronic CSC is characterized by multifocal or diffuse decompensation of RPE associated with persistent detachment of neurosensory retina. This might lead to cystoid macular degeneration, foveal atrophy and damage to the foveal photoreceptor layer, consequently resulting in irreversible significant visual loss. Photodynamic therapy (PDT) was proposed for the treatment of chronic CSC. Modified parameters of PDT such as shortening of the time of laser emission and reduction of a total light energy have been suggested to reduce the irreversible damages induced by conventional PDT. Recently, intravitreal injection of antibody to vascular endothelial growth factor(VEGF) was proposed as a new treatment option based on the effect of anti-permeability. Several reports demonstrated acceptable outcomes after intravitreal bevacizumab injection, one of anti-VEGF agent. But the clinical results with ranibizumab are not reported yet. The purpose of this study is to compare the efficacy and safety of intravitreal ranibizumab injection versus low-fluence PDT in the treatment of chronic CSC.

Inclusion Criteria:

1. best-corrected visual acuity (BCVA) between 0.0 and 1.0 logarithm of the minimal angle of resolution (logMAR)
2. presence of subfoveal fluid persisting for 3 months or more on optical coherence tomography (OCT)
3. presence of leakage and multifocal/diffuse RPE decompensation on fluorescein angiography (FA)
4. choroidal vascular hyperpermeability and abnormal dilation of choroidal vasculature on indocyanine angiography (ICGA)

Exclusion Criteria:

1. previous treatment, such as laser photocoagulation, PDT, intravitreal injection of steroid or anti-VEGF agent
2. evidence of choroidal neovascularization
3. any other ocular diseases that could affect visual acuity
4. systemic steroid treatment in the previous 12 months
5. media opacity such as cataract that could interfere with adequate acquisition of OCT, FA and ICGA images