Cause

Causes of retinal detachment are:

• Tears or holes in the retina. These may lead to retinal detachment by allowing fluid from the middle of the eye (vitreous gel) to collect under the retina. A common cause of retinal tears is posterior vitreous detachment (PVD). An eye or head injury or other eye disorders, such as lattice degeneration, a condition in which the retina becomes very thin, may also cause tears or holes in the retina.
• Traction on the retina. Traction pulls the retina away from the layers beneath it. The most common cause of this problem is proliferative diabetic retinopathy, a condition that leads to the growth of scar tissue that can pull on the retina.
• Fluid buildup under the retina. Fluid buildup causes the layers of the retina to separate, resulting in retinal detachment. Fluid buildup may be caused by inflammation or disease in the retina, in the layer just beneath the retina (choroid), in blood vessels, or in tissues in the eye.

For more information about and pictures of the eye and how it works, see Eye Anatomy and Function.

Symptoms

Most cases of retinal detachment begin when the vitreous gel that fills the center of the eye shrinks and separates from the retina (called posterior vitreous detachment, or PVD). Symptoms of PVD include:

• Floaters in your field of vision. Floaters are thick strands or clumps of solid vitreous gel that develop as the gel ages and breaks down. Floaters often appear as dark specks, globs, strings, or dots. Floaters may also be caused by loose blood or pigment from tears in the retina.
• Flashes of light or sparks when you move your eyes or head. These are easier to see against a dark background. The brief flashes occur when the vitreous gel tugs on the retina (vitreous traction). These flashes usually appear at the edge of your visual field.

Having floaters or flashes does not always mean that you are about to have a retinal detachment, but you should not ignore these symptoms. Call your doctor to discuss whether you need to have an eye exam.

If you have new or sudden flashes or floaters, darkness over part of your visual field, or a new loss of vision that does not go away, call your eye doctor or regular doctor right away. Floaters and flashes may be warning signs of retinal detachment. A sudden shower of what appear to be hundreds or thousands of little black dots across the field of vision is a distinctive sign of blood and/or pigment in the vitreous gel and may indicate a retinal detachment. This requires immediate medical attention.

In rare cases, a retinal detachment can occur without warning. The first signs may be:

• A shadow or curtain effect across part of your visual field that does not go away. Because detachments usually affect peripheral (side) vision first, you may not notice a problem until the detachment has gotten bigger.
• New or sudden vision loss. Vision loss caused by retinal detachment tends to get worse over time. Sudden vision loss is a medical emergency.