Indocyanine Green Angiography (ICG) is a diagnostic procedure which utilizes digital photography to produce a choroidal map of the retina by tracing the contrast dye (indocyanine green) as it slowly sinks into the tissue of the eye. This is another excellent method for visualizing retinal circulation.In contrast to fluorescein angiography (FA), ICG is of particular value in studying choroidal circulation while investigating macular disease.
by tracing the flow of a contrast dye (fluorescein) through blood vessels in the eye. These digital images help doctors evaluate the retina and diagnose and track problems such as diabetic retinopathy, macular degeneration, abnormal vessel growth, swelling, leaking, retinal detachment, cancer and/or tumors.
The ICG exam begins after the patient is comfortably seated and positioned face first while relaxing in front of the retinal camera by an ophthalmic technician. After an early pair of digital photos are taken for a baseline image and to insure clarity and focus; the patient is then injected in the arm with the contrast dye (indocynanine green).Within 1 minute after the injection of the contrast dye and the immediate removal of the needle; the ophthalmic technician proceeds to take the first pair of retinal photographs as the indocynanine green highlights the eye tissue for the ophthalmic camera. This is followed by 3 more series of digital images at 5 minute intervals for comparison, which conclude at15 minutes after the initial injection of contrast dye.
The ICG exam generally takes about 15-20 minutes to perform.