If the eye condition you have requires diagnostic testing to assess blood flow within the retina, such as macular degeneration, diabetic retinopathy, or retinal vein occlusion to name a few, it is important that you are aware of the different testing options available to you.
INTRAVENOUS FLUORESCEIN ANGIOGRAPHY
The first testing option is called intravenous fluorescein angiography or IVFA. In this test, a special dye called fluorescein is injected into the bloodstream through an intravenous needle in the arm. As the dye flows through the retina, a technician takes pictures to allow the ophthalmologist to see the pattern of blood flow in the eye and detect any abnormalities. Your skin will appear yellow for a day or two afterwards because of the dye. The colour will disappear as the dye is filtered out of the body by the kidneys, and your urine will turn dark orange for approximately 24 hours following the test. IVFA requires the placement of an intravenous needle and carries a 1/10,000 risk of a severe allergic reaction. It is not uncommon for patients to feel nausea as the dye is injected. Because of these issues, IVFA is only performed in a hospital setting, and as a result there are sometimes delays associated with accessing this test. IVFA remains the gold standard for assessing blood vessels in the retina. It is covered by OHIP.
The second testing option is called OCT angiography. This test uses a special imaging technology that is able to detect the movement of blood cells within blood vessels to assess blood flow within the retina. Unlike IVFA, it does not require an intravenous needle to be inserted and also does not require the use of fluorescein dye, and therefore is safe enough to be performed in our office. OCT angiography is new technology and is not completely interchangeable with IVFA, but early reports are very positive regarding its usefulness in diagnosing and monitoring retinal disorders. It is not yet covered by OHIP. It is our hope that the test will be covered by OHIP sometime in the future.