How is diabetic retinopathy diagnosed?

When you see an ophthalmologist for DR assessment and diagnosis, you will have eye drops administered to enlarge (dilate) the pupils temporarily so that they can examine the retina and macula.

Sometimes, in addition to clinical examination, your ophthalmologist may order additional tests and evaluations, such as:

• Fundus Fluorescein Angiogram (FFA)
  In this test, a fluorescent dye is injected into a vein in your arm. Over the next few minutes, photographs are taken of the blood vessels in your eye as the dye passes through. This helps to highlight abnormal or "leaky" blood vessels, or areas of the retina where blood flow is insufficient. Uncommonly, complications due to the injection can arise, such as nausea, or in very rare cases, severe allergic reactions or heart problems.
  
  
• Optical Coherence Tomography (OCT)
  OCT is similar to an ultrasound scan, except that the latter uses sound waves to capture images. OCT uses light waves instead, and can capture very detailed, cross-sectional images of the retina and macula. OCT is a good method for the assessment of DME. OCT imaging is very fast and convenient. You will be asked to place your head on a chin rest and hold still for several seconds while the images are obtained. The light beam used is painless, and unlike X-rays, does not involve any radiation.
   
  
• Optical Coherence Tomography Angiography (OCT-A)
  In some cases, the blood vessels in the retina can be examined with OCT-A. Based on the same technology as OCT, OCT-A uses light waves to capture very detailed images of blood vessels in the eye.  OCT-A does not require any fluorescent dye injection, and also does not involve any radiation.
  
  

 OCT scan showing diabetic macular edema