Comparative analysis of retinal structure was performed in patients with POAG and control healthy group using spectral OCT and histology. An apparent similarity of tomographic and histological patterns of retinal changes was found in patients with POAG. These results make OCT potentially appropriate method for vital examination of retinal structure in glaucomatous eyes including early stages of the disease. Degeneration of all retinal layers is revealed. Blood flow deficiency due to sclerosis and hyalinosis of uveal vessels is considered to be an immediate cause of outer and intermediate retinal layers degeneration.