Central serous chorioretinopathy (CSC) is a self-limiting disease that usually associated with good visual prognosis. In some cases, however, CSC may persist and result in permanent retinal or retinal pigment epithelium (RPE) damage. Therefore, if the disease is persistent beyond the acute phase, an active treatment should be considered to prevent an irreversible damage to retinal function.

The pathophysiology of CSC is associated with abnormal choroidal circulation. Indocyanine green angiography (ICGA) has revealed dilated and congested choroidal vessel and leakage into the extracellular space that appears as area of hyperfluorescence seen in middle and late phase in eyes with CSC.

A goal of treatment has been focused on reducing choroidal hyperpermeability. Currently, photodynamic therapy with verteporfin (PDT) and intravitreal anti-VEGF (vascular endothelial growth factor)antibody injection are being tried in order to treat chronic CSC. PDT reduces choroidal hyperpermeability by inducing hypoperfusion of the choriocapillaris in the short term and choroidal vascular remodeling over time. Intravitreal anti-VEGF injection for the treatment of CSC also effectively reduces choroidal hyperpermeability by blocking vascular leakage. Both methods have shown to be effective with good functional outcome for treating chronic CSC in many reports, but until now there is no established standard treatment protocol for chronic CSC.

Bevacizumab (Avastin) and ranibizumab (Lucentis) have been used widely as anti-VEGF therapeutic agent for the treatment of age related macular generation (AMD) and macular edema of various reasons. A newly developed anti-VEGF drug, aflibercept (Eylea○R), shows higher affinity to VEGF and has a longer duration of effect in the vitreous.FDA approved aflibercept to treat wet type AMD and macular edema due to central retinal vein occlusion.

Until now, no study has been reported on the efficacy and safety of aflibercept for treating CSC. The aim of this study is to evaluate the efficacy and safety of intravitreal aflibercept injection for the treatment of idiopathic CSC

Single-center Double blind randomized Phase 2 interventional parallel study.

Group A : 2mg intravitreal Aflibercept(Eylea) injection at baseline, at 1 month, and at 2 month Group B : Sham injection at baseline, at 1 month, and at 2 month

At 3 month, 4 month, 5 month, and 6 month, PRN treatment of aflibercept injection or half-fluence photodynamic therapy may be done, if one of following conditions is fulfilled.

The PRN treatment method was decided by investigator's discretion.

Of patient who had persistent intra- or subretina fluid on SD-OCT

1. Central subfield thickness is not decreased to more than 50 micrometer compared with baseline central subfield thickness
2. Best-corrected ETDRS letter score dose not increased more than 5 letters than baseline (because of the persistent CSC).
3. Central subfield thickness is thicker than the previous exam
4. BCVA letter score is worse than the previous exam (because of the persistent CSC)

Inclusion Criteria:

• Clinical diagnosis of idiopathic CSC.
• 18 to 60 years old, woman and man.
• Subretinal fluid is found at OCT.
• Symptom duration is from 6 weeks to 4 months.
• Patient who agree to participate in the study.

Exclusion Criteria:

• Patient who was treated previously for CSC
• Patient who has choroidal neovascularization or other macular disease
• Patient who has other ophthalmologic disease that may affect patient's vision.
• History of any intraocular surgery, except cataract extraction prior to 3 months
• Patient who has active intraocular inflammation or infection
• Patient who has uncontrolled glaucoma IOP was more than 25 mmHg in spite of anti-glaucoma medication Visual field defect which affect best corrected visual acuity
• Patient who has been used systemic or topical carbonic anhydrase inhibitor within 1 month
• Cushing syndrome
• History of intravitreal steroid injection to study eye
• Patient who has been used or plan to use systemic drug which is toxic to crystalline lens, retina or optic nerve.
• Patient who has a known allergy to fluorescein or ICG
• Pregnant or breast-feeding woman
• Patient with contraindication to aflibercept Ocular or periocular infection Active severe intraocular inflammation Known hypersensitivity to aflibercept or to any of the excipients