Chronic Central Serous Chorioretinopathy (cCSC): Differential Diagnosis to Choroidal Neovascularisation (CNV) Secondary to Age-Related Macular Degeneration (AMD)

Central neurosensory detachments (NSD) with time-dependent height constitute a disease called central serous chorioretinopathy (CSC), if not arising from uveitis, choroidal neovascularisations (CNV) or leaking retinal vessels. In 10 % of these patients, CSC develops into a chronic disease with recurrent NSD, atrophy of photoreceptors and severe drop in visual acuity. This review article summarises recent progress in understanding this disease and its appearance in funduscopy, FLA, ICG, OCT, autofluorescence as well as its progress, therapy and possible development into secondary CNV. The provided examples illustrate the progression of acute CSC into chronic CSC and with CNV over years. The different appearance of polypoidal choroidal vasculopathy (PCV) in ICG and some of the signs of atypical chronic CSC are discussed. To distinguish between cCSC and wet AMD - both exhibiting leakage in FLA - typical signs are helpful, e.g., "gravitational tracks", retinal precipitates and missing drusen. However, in small lesions, it may be difficult or almost impossible to ensure the correct diagnosis of the underlying disease. The same holds for occult and classic secondary CNV in cCSC vs. CNV in AMD, where photodynamic therapy (PDT) can be successful only in cCSC-CNV and in cCSC without CNV. Corticosteroids often lead to further impairment, even in cases of atypical cCSC, when frequently misdiagnosed as uveitis. As a duration of NSD of more than 4 months is suspected to induce an impairment of photoreceptors, regular examinations are necessary not only in chronic CSC but also after acute CSC (as this form can develop into chronic CSC), while effective therapies are available to resolve the NSD (PDT, anti-VEGF).