What is progressive retinal atrophy?
The cells of the retina receive light stimuli from the external environment and transmit the information to the brain where it is interpreted to become vision. In progressive retinal atrophy (PRA), deterioration of the retinal cells causes blindness. The retina lines the back of the eye. The inner layer is the neural retina (called simply the retina) which has 9 layers, the outermost of which consists of the photoreceptor cells – the rods and cones. The outer layer of the retina is the retinal pigmented epithelium (RPE). In dogs the retina is not mature until 6 or 7 weeks of age. The term progressive retinal atrophy covers several types of inherited degeneration (deterioration) of the retina. Sub-classifications of PRA are based on the age at which dogs show signs of the disease and the type of retinal cell which is affected. Generalized PRA: These diseases affect primarily the photoreceptor cells. Both eyes are similarly affected and dogs eventually become totally blind. i) Early onse
