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

Abstract

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). 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 metamorphopsia. The sensitivity, specificity, and accuracy in the diagnosis of metamorphopsia were calculated against the Amsler grid. 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. 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.