Comparison of Macular Thickness in Diabetic Macular Edema Using Spectral-Domain Optical Coherence Tomography and Time-Domain Optical Coherence Tomography

Abstract

Purpose. To compare the macular thicknesses in diabetic macular edema (DME) measured with spectral-domain optical coherence tomography (SD-OCT) and time-domain (TD) OCT.Patients and Methods.The average macular thicknesses of 50 eyes of 29 patients with DME were measured using SD-OCT and TD-OCT.Results.The mean macular thicknesses measured with TD-OCT and SD-OCT were401.5±117.8 μm (mean ± SD) and446.2±123.5 μm, respectively. The macular thicknesses measured with the two devices were well correlated (Pearson's product moment correlation,r=0.977,P<0.001). A significant correlation was found between the best-corrected visual acuity and the retinal thickness measured by TD-OCT and SD-OCT (Pearson's product moment correlation, TD-OCT,r=0.34;P<0.05; SD-OCT,r=0.32;P<0.05).Discussion.The mean macular thickness measured with SD-OCT was about 45 μm thicker than that measured with TD-OCT. Attention should be paid when comparing data obtained using different OCT machines.