Inclusion Criteria:  40 individuals were required to have Proliferative Diabetic Retinopathy (PDR); 40 were required to have Non-PDR; 40 were required to be healthy, without any systemic disease.  Exclusion Criteria:  Glaucoma, Ocular trauma sequelae, Pathological myopia, Non-diabetic retinopathy, A history of previous ocular surgery, Endocrine disorders (e.g.,thyroidopathy, adrenal gland disorders, pituitary pathologies), Opacities interfering with fundus examination (e.g., corneal opacity, lens opacity, vitreous cloudiness other than diabetic haemorrhage).