INDOCYANINE GREEN ANGIOGRAPHY of FUNDUS

Indocyanine green angiography (ICG) is a diagnostic test that uses a special dye and a camera to take detailed images of the blood vessels in the retina, the light-sensitive layer of tissue at the back of the eye. Like fundus fluorescein angiography (FFA), ICG is used to detect and diagnose a variety of eye conditions, including diabetic retinopathy, age-related macular degeneration, and retinal detachment.

The ICG test begins with an injection of the dye indocyanine green into a vein in the arm. The dye circulates through the bloodstream and reaches the blood vessels in the retina, making them visible on the camera. The camera captures a series of images of the retina as the dye is circulating through the blood vessels.

The ICG test is typically performed by an eye doctor, such as an ophthalmologist or optometrist. The procedure usually takes about 30 minutes to an hour, and the patient is usually able to return to normal activities immediately after the test.

Like FFA, ICG is a safe and well-tolerated procedure, however, some people may experience mild side effects such as a warm sensation or a metallic taste in the mouth, or an allergic reaction to the dye. These side effects are usually temporary and will resolve on their own.

The images obtained during the ICG test are analyzed by the eye doctor to detect any abnormalities in the blood vessels of the retina, such as leakage, blockages, or abnormal growth of new blood vessels. The test can also detect changes in the retina itself, such as the presence of scar tissue or fluid accumulation.

One of the main advantages of ICG over FFA is that it can detect blood flow in deeper layers of the retina, including the choroid, a layer of blood vessels located between the retina and the sclera. This makes it particularly useful in the diagnosis and management of choroidal neovascularization, a condition characterized by the growth of new blood vessels in the choroid that can lead to vision loss.

It's important to note that ICG is not a substitute for a comprehensive eye exam. An eye exam should be done regularly to detect and treat any eye problem as soon as possible.

In conclusion, Indocyanine green angiography (ICG) is a diagnostic test that uses a special dye and a camera to take detailed images of the blood vessels in the retina. It's used to detect and diagnose a variety of eye conditions, particularly choroidal neovascularization, and to monitor the progression of the disease and the effectiveness of treatment. It's a safe and well-tolerated procedure, however, it should be done in conjunction with regular comprehensive eye exams to detect and treat eye problems as soon as possible.

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