The retina is the light sensitive tissue in the back of the eye. When light hits the retina, the image is transmitted via the optic nerve to the brain. Retinal detachment occurs when there is a parting of this light sensitive tissue from the nourishing, supportive tissues underneath. The detachment can be focal or involving the entire retina. Symptoms of retinal detachment include sudden blindness, lethargy, and a poor appetite. Causes of detachment are numerous: elevated blood pressure, systemic inflammatory conditions (due to infection or immune mediated events), trauma, and tumors. Your veterinarian can diagnose retinal detachment by visualizing the inner portions of the eye with a light source; the retinal tissue can be seen floating away from the back of the eye. Small areas of detachment may require ultrasound to visualize. Once a definitive diagnosis of retinal detachment is made, further testing (e.g.: blood work, blood pressure, imaging) must be done to determine the cause of the detachment. Treatment should be done without delay and aimed at treating the underlying cause to provide the best chances of restoring vision. Repair of the retina may require surgical intervention; occasionally enucleation (surgical removal of the eye) may be necessary to relieve pain in an already blind eye.