Inner and outer retinal thickness mapping of nonproliferative diabetic retinopathy by spectral-domain optical coherence tomography.

Abstract

To report inner retinal thickness (IRT), outer retinal thickness (ORT), and total retinal thickness (TRT) mapping of nonproliferative diabetic retinopathy (DR). Spectral-domain optical coherence tomography (SD-OCT) images were obtained in 31 study participants with nonproliferative DR. Semi-automated software generated IRT, ORT, and TRT maps. IRT, ORT, and TRT in each macular subfield were compared between groups with and without increased central subfield thickness. There were statistically significant differences in IRT, ORT, and TRT between groups (P < .007). In participants with nonproliferative DR with increased central subfield thickness, TRT was significantly increased in parafoveal and perifoveal inferior subfields (P < .001). In these subfields, both IRT and ORT were significantly increased (P < .007) compared to those in participants without increased central subfield thickness. Mapping of inner and outer retinal thickness shows promise for monitoring depth-specific thickness alterations by macular subfields due to DR.