Information on Common Eye Disorders
 
Retina And Vitreous

Fluorescein Angiography
 
CMV retinitis is a serious eye infection of the retina, the light-sensing nerve layer that lines the Fluorescein angiography, a clinical test to look at blood circulation inside the back of the eye, aids in the diagnosis of retinal conditions associated with diabetes, age-related macular degeneration, and other eye abnormalities. The test can also help follow the course of a disease and monitor its treatment. It may be repeated on multiple occasions with no harm to the eye or body.

Fluorescein, a harmless orange-red dye, is injected into a vein in the arm. The dye travels through the body to the blood vessels in the retina, the light-sensitive nerve layer at the back of the eye. A special camera with a green filter flashes a blue light into the eye and takes multiple photographs of the retina. The technique uses regular photographic film. No X-rays are involved.

If there are abnormal blood vessels, the dye leaks into the retina or stains the blood vessels. Damage to the lining of the retina or atypical new blood vessels may be revealed as well. These abnormalities are determined through a careful interpretation of the photographs by an ophthalmologist.

The dye can discolor skin and urine until it is removed from the body by the kidneys. There is little risk in having fluorescein angiography, though some people may have mild allergic reactions to the dye. Severe allergic reactions have been reported but very rarely. Being allergic to X-ray dyes with iodine does not mean you'll be allergic to fluorescein. Occasionally, some of the dye leaks out of the vein at the injection site, causing a slight burning sensation that usually goes away quickly.
Indocyanine Green Angiography (ICG)
CMV retinitis is a serious eye infection of the retina, the light-sensing nerve layer that lines the ICG angiography is a clinical test used to detect abnormal blood vessels in the choroid, the layer of blood vessels under the retina. These abnormal blood vessels, typically associated with macular degeneration, may cause bleeding, scarring, and vision loss. If the blood vessels can be restricted by laser surgery, vision loss may be stabilized or improved.

Indocyanine, a harmless green dye, gives off infrared light. When injected into the bloodstream, the dye travels through the veins to the blood vessels in the eye. A video camera connected to a computer picks up the infrared light and makes a picture of the blood's circulation. No film or x-rays are involved.

Following the test, the liver removes the dye. There is little risk in having an ICG angiogram. Some people may have mild allergic reactions and, although rare, a few severe allergic reactions have been reported in people allergic to iodine, X-ray dyes and shellfish.
Lattice Degeneration

Lattice degeneration is thinning and weakening of the retina, the light-sensitive layer of cells lining the back of the eye, that can lead to a retinal tear.

The vitreous, a clear gel-like substance that fills the inside of the eye, is contained in a sac loosely attached to the retina. As one ages, the vitreous takes on a more fluid consistency and the sac sometimes separates from the retina. In lattice degeneration, there are places where the sac is strongly attached to the retina and pulls on it. This pulling weakens the retina and creates lattice lesions that look like white crisscrossing lines on the retina.

If part of the vitreous sac becomes detached from the retina, the friction and pulling where it is still attached can create a tear in the retina. Lattice degeneration can sometimes cause retinal detachments when holes or tears in the lattice formation permit vitreous fluid to get under the retina.

Fortunately, most people with lattice degeneration do not develop a retinal detachment. Preventive treatment of lattice degeneration has not been shown to prevent retinal detachment, but lattice degeneration should be monitored. If you have a history of lattice degeneration, you should be aware of the symptoms of retinal tears and detachment.