Quantification of Metamorphopsia in Resolved Idiopathic Central Serous Chorioretinopathy: An Analysis Using M-CHARTS, Amsler Grid, and Optical Coherence Tomography

Abstract

Purpose: To quantify metamorphopsia in patients with resolved idiopathic Central Serous Chorioretinopathy (CSCR) using M-CHARTS and compare the results with the traditional Amsler grid and optical coherence tomography (OCT). Patients and Methods: For the purpose of this study, all consecutive cases of patients with resolved CSCR were evaluated for metamorphopsia (using the standard Amsler grid and M-CHARTS) and spectral domain OCT. The OCT images were analyzed for the following five parameters: central macular thickness, pigment epithelial detachment, retinal pigment epithelial bumps, discontinuation in the inner segment/outer segment junction or the external limiting membrane, fibrinous exudates in the subretinal space, and hyperreflective dots in the intraretinal and/or subretinal layer. Binary logistic regression was used to find the association between metamorphopsia and foveal morphology. Cohen’s Kappa was used to determine the agreement between the M-CHARTS and Amsler grid for diagnosing metamor-phopsia. The sensitivity, specificity, and accuracy in the diagnosis of metamorphopsia were calculated against the Amsler grid. Results: Of 41 eyes, Amsler Grid detected metamorphopsia in 39.02%, and M-CHARTS detected metamorphopsia in 53.66%. The agreement rate of detection between the two tests was moderate (Kappa=0.52). M-CHARTS had a sensitivity of 87.50%, a specificity of 68.00%, a positive predictive value of 63.64%; and a negative predictive value of 89.47% for the diagnosis of metamorphopsia compared to the Amsler grid. The presence of PED in OCT was significantly associated with metamorphopsia. Conclusion: M-CHARTS can be a useful ancillary test to detect and quantify metamorphopsia even after fluid resolution in CSCR. Structural changes in macular morphology as observed with OCT can predict the likelihood of metamorphopsia.