If your eye doctor needs to examine your retina, she or he may suggest optical coherence tomography. OCT is a noninvasive test that uses light waves to create 3D or cross-section images of the retina’s layers. The images allow the doctor to compare the thickness of your retinal layers with those in a healthy eye. This helps achieve an accurate diagnosis.

You’ll receive eye drops to dilate the pupils, and you’ll sit in front of the OCT device while resting your chin on a support. Scanning takes about five to ten minutes.

OCT enables diagnosis of eye conditions such as:

• Macular degeneration
• Glaucoma
• Diabetic eye disease
• Optic nerve damage
• Macular holes

Because it uses light rays, OCT isn’t suited for conditions that prevent light from passing through your eyes, such as cataracts or bleeding.