What OCT imaging shows about your eye health
A closer look at optical coherence tomography — the painless scan that reveals what a standard eye exam cannot.
What is OCT?
Optical coherence tomography (OCT) is a non-invasive imaging test that uses light waves to capture detailed, cross-sectional pictures of the retina — the light-sensitive tissue at the back of the eye. It works much like an ultrasound, but uses light instead of sound, producing images with micrometre-level detail in just a few seconds.
Why it matters
A standard eye exam can show the surface of the retina, but OCT reveals its individual layers — including fluid, swelling or thinning that is not visible to the naked eye. This makes it one of the most useful tools for catching retinal disease early, often before a patient notices any change in vision.
Conditions OCT helps diagnose and monitor
- Diabetic macular edema — swelling in the macula from diabetic eye disease
- Age-related macular degeneration — both the dry and wet forms
- Macular holes and epiretinal membranes
- Response to anti-VEGF injections over time
- Glaucoma-related changes to the optic nerve
What to expect during the scan
OCT is quick, painless and requires no needles or injections. Patients rest their chin on a support while the machine captures images of the retina, usually while the pupils are dilated for the clearest view. Most scans take under 10 minutes, and results are available the same visit.
Key takeaway
OCT gives Dr. Abir a detailed, layer-by-layer view of the retina — turning what would otherwise be invisible changes into clear, trackable data that guides treatment decisions.