Evaluation of the inclusion of spectral domain optical coherence tomography in a telemedicine diabetic retinopathy screening program

To evaluate whether combining spectral domain optical coherence tomography with monoscopic fundus photography using a nonmydriatic camera (MFP-NMC) improves the accuracy of diabetic macular edema (DME) referrals in a teleophthalmology diabetic retinopathy screening program.We conducted a cross-sectional study with all diabetic patients aged 18 years or older who attended screening from September 2016 to December 2017. We assessed DME according to the three MFP-NMC and the four spectral domain optical coherence tomography criteria. The sensitivity and specificity obtained for each criterion were estimated by comparing them with the ground truth of DME.This study included 3,918 eyes (1,925 patients; median age, 66 years; interquartile range, 58-73; females, 40.7%; once-screened, 68.1%). The prevalence of DME ranged from 1.22% to 1.83% and 1.54% to 8.77% on MFP-NMC and spectral domain optical coherence tomography, respectively. Sensitivity barely reached 50% in MFP-NMC and less for the quantitative criteria of spectral domain optical coherence tomography. When macular thickening and anatomical signs of DME were considered, sensitivity increased to 88.3% and the false DMEs and non-gradable images were reduced.Macular thickening and anatomical signs showed the highest suitability for screening, with a sensitivity of 88.3% and a specificity of 99.8%. Notably, MFP-NMC alone missed half of the true DMEs that lacked indirect signs.