Aim. A cross-sectional study was performed to examine the alterations of the retinal pigment epithelium– (RPE–) photoreceptor complex layer in type 2 diabetes mellitus (DM) without diabetic retinopathy (DR), using spectral-domain optical coherence tomography (SD-OCT). Methods. Patients with type 2 DM without DR and healthy controls without DM were recruited. All participants underwent examinations including SD-OCT. The thickness measurements of the retinal neural layers were calculated after automatic segmentation. An independent-sample t-test was used to compare the means of the thickness of retinal neural layers in patients with DM and healthy controls. Results. Sixty-seven eyes from 67 patients with DM and 30 eyes from 30 healthy controls were included in this study. No significant differences were found in age (P = 0.601), gender (P = 0.560), axial length (P = 0.414), best-corrected visual acuity (P = 0.963), or intraocular pressure (P = 0.112) between the two groups. There were significant increases in the hemoglobin A1c value (P < 0.001) and mean thicknesses of the RPE–photoreceptor complex layer in the foveal area (P = 0.027) and paracentral area (P = 0.001) in the DM group compared to the control group, whereas the thickness of the retinal nerve fiber and ganglion cell layers in the foveal and paracentral areas between the two groups showed no significant differences. Conclusion. Lesions in the RPE–photoreceptor complex are present without vascular abnormalities, which may precede the alterations of ganglion cells in patients with type 2 DM.

Objective. To investigate the thicknesses of macular inner retinal layers in children with anisometropic amblyopia using spectral domain optical coherence tomography (SD-OCT). Methods. Thirty-seven children with anisometropic amblyopia and fifty-seven children with normal vision were recruited in the study. Both eyes of children with anisometropic amblyopia and the right eyes of normal controls underwent scanning with the Spectralis OCT. The segmentation of retinal layers was performed automatically to measure individual inner retinal layers in the five sectors of the macular. An independent sample t -test was applied to compare the mean layer thicknesses of anisometropic eyes and fellow eyes with those of control eyes. Results. There was no significant difference in the total macular thickness between amblyopic and control eyes. However, in the peripheral macular area, three of the four quadrants of both the ganglion cell layer (GCL) and the inner plexiform layer (IPL) thicknesses were significantly reduced in amblyopic eyes compared to control eyes. Moreover, two of the four quadrants of the GCL thickness and three of the four quadrants of the IPL thickness in the peripheral macular area were significantly reduced in fellow eyes than in control eyes. Conclusion. The SD-OCT data revealed differences in the thicknesses of some macular inner retinal layers in both eyes of children with anisometropic amblyopia compared with those with emmetropia, indicating that structural changes might exist in the retina of children with amblyopia.