Risk Factors for Retinal Detachment
There are a number of risk factors for retinal detachment. These include:
- Cataract surgery
- Diabetic retinopathy and retinopathy of prematurity
- Family history
- Myopia (nearsightedness)
- PVD complicated by small tears (usually in patients over 50)
- Retinal detachment in one eye increases risk for the other eye
- Thinning of the retina
- Traumatic injury to the eye
Signs and Symptoms of Retinal Detachment
Initial symptoms of PVD are called flashes and floaters. As the vitreous shrinks and condenses, it may "tug" on the retina. When this happens, people often see a split-second flash of light, usually in their peripheral vision.
As the vitreous shrinks away from the retina, small fragments of the retina may break off. The vitreous also condenses and may form opaque spots. The fragments and opacities (floaters) appear as small circles, specks, or fine threads in the vision field.
In most people with PVD, floaters become less noticeable as the vitreous continues to detach from the retina. They generally settle to the bottom of the eye, moving out of the field of vision. There is no treatment for floaters and it may take several months for them to become less bothersome or disappear completely. Surgical removal of floaters is controversial because the risk outweighs any benefit.
The sudden appearance of spots or flashes can indicate a tear in the retina. A sudden increase in the number and size of floaters may also be a warning that the retina is tearing. This is sometimes referred to as a "shower of floaters."
Wavy or watery vision may also be a sign that the retina is detaching. Sometimes people notice a dark shadow or the appearance of a "curtain" being pulled over their field of vision. This generally is experienced in the peripheral (side) vision, which is where retinal detachment often begins. Blurred central vision indicates that retinal detachment is progressing and the result is significant, permanent vision loss unless it is repaired.
Retinal detachment usually develops gradually, causing noticeable symptoms, but in some cases it occurs suddenly. This causes total vision loss in the affected eye. Total vision loss can also be caused by a retinal tear that bleeds into the vitreous.
Retinal Detachment Diagnosis
The earlier the diagnosis is made, the greater the chance to restore vision. Diagnosis is based on symptoms and a thorough examination of the retina.
An ophthalmoscope is used to examine the retina. This is a small hand-held instrument consisting of a battery-powered light and a series of lenses that is held up to the eye. The doctor is able to see the retina and check for abnormalities by shining the light into the eye and looking through the lens. Eye drops are placed in the eyes to dilate the pupils and provide better visualization. When this is done, an indirect ophthalmoscope is used. This instrument is worn on the specialist's head and a lens is held in front of the patient's eye. It allows a greater, wider view of the retina.
Examination with a slit lamp microscope may also be done. This microscope enables the doctor to examine the different parts of the eye under magnification. After instilling drops to dilate the pupil, the slit lamp is used to detect retinal tears and detachment.
A visual acuity test may also be indicated to assess vision loss. This test involves reading letters from a standard eye chart.