When a retinal tear occurs, retinal blood vessels may also be torn. When this happens, blood spills into the vitreous cavity; this is called a vitreous hemorrhage. Becauses there is a tear in the retina, a retinal detachment may also occur. The combination is difficult to treat because the hemorrhage prevents the surgeon from seeing the retina and finding the hole. In such a case, a special technique called ultrasonography is necessary to help make the diagnosis of retinal detachment beneath the hemorrhage.

Ultrasonography is a harmless and painless test. It is like the sonar on a submarine. Sound waves are sent into the eye. They travel through the hemorrhage and bounce off of the retina. The returning sound waves make an image on a monitor and allow the doctor to see whether the retina is attached or detached.

If a patient has a combined vitreous hemorrhage and retinal detachment, a vitrectomy must be performed to remove the blood so that the surgeon can see the retina. Also, a scleral buckle is placed around the eye. Because of the combination of retinal detachment and vitreous hemorrhage, the eye is at high risk for developing proliferative vitreoretinopathy.