Segmentation of spectral domain OCT volume scans of patients with no or minimal diabetic retinopathy

Purpose A comparison of thickness measurements of segmented spectral domain optical coherence tomography (OCT) derived topographic maps of patients with no or minimal diabetic retinopathy (DR) versus healthy controls. Methods Ninety‐nine patients, 44 with type 1 DM, and 36 with type 2 DM, with no or minimal DR underwent full ophthalmic examination, fundus photography and spectral domain OCT (3D OCT‐1000, Topcon). Following automated segmentation the mean thickness was calculated for 6 layers: 1/ Retinal Nerve Fibre Layer (RNFL), 2/ Ganglioncell layer (GCL) + Inner Plexiform Layer (IPL), 3/ Inner Nuclear Layer, 4/ Outer Plexiform Layer, 5/ Outer Nuclear Layer + Inner Segments (photoreceptor), 6/ Outer Segments (photoreceptor), in the ETDRS defined regions of the macula and compared to 76 age and sex matched healthy controls. Results The total retinal thickness in the diabetic patients was reduced compared to the healthy controls. In the diabetic patients both the mean RNFL and the mean OPL were significantly (p