REGIONAL SCLERAL THICKNESS AS A RISK FACTOR FOR CENTRAL SEROUS CHORIORETINOPATHY.

Abstract

To evaluate regional sclera thicknesses as possible risk factors for central serous chorioretinopathy (CSC). Patients with CSC and controls were evaluated with contact B-scan ultrasonography using a 20 Mhz concentric phased array ultrasound unit and enhanced depth imaging optical coherence tomography to measure the scleral thickness at the equator and posterior pole. The resultant data were evaluated using univariate analysis and generalized estimating equations. There were 40 patients with CSC with a mean age of 58 years and 23 controls with a mean age of 60.7 years (P = 0.31). The mean subfoveal scleral thicknesses were 1.3 mm in the CSC group and 0.86 mm in the control group (P < 0.001). The mean equatorial scleral thickness was 0.61 mm in the CSC group and 0.42 mm in the control group (P < 0.001). Using generalized estimating equations, the equatorial scleral thickness (P = 0.001), posterior scleral thickness (P < 0.001), and subfoveal choroidal thickness (P = 0.032) were independent predictors of CSC. Once these variables were entered into the equation, neither sex nor age were significant predictors. Generalized estimating equation analysis showed that equatorial, but not posterior, scleral thickness was a significant predictor of subfoveal choroidal thickness. Scleral thicknesses of the posterior and equatorial portions of the eye were found to be significant predictors of CSC, consistent with what was proposed in the theory of venous overload choroidopathy. Direct measurement by high resolution ultrasonography provides independent information about specific regions of the sclera and also avoids making speculative assumptions derived from anterior segment measurements.