Figure 6. Ganglion cell layer analysis on optical coherence tomography (μ) in different diabetic retinopathy stages. *Control versus NPDR and PDR: significant differences, with the control having higher GCA thickness. NoDR versus PDR: significant difference, with NoDR having higher GCA thickness. NPDR versus PDR: no significant differences. OCT - optical coherence tomography, GCA - ganglion cell analysis, NoDR - no diabetic retinopathy, NPDR - non-proliferative diabetic retinopathy, PDR - proliferative diabetic retinopathy.