OCT Scanning

When deciding whether or not to have an OCT scan, people sometimes say to me "See if you find anything during the eye examination that requires a scan."

But if I've found a problem just from looking in the eye, I usually don't need a scan to confirm it. The point about the OCT is that it enables us to see beneath the surface, to give information that I don't already know; to see what I haven't already seen.

This is particularly useful for glaucoma and macular degeneration, which I talk about separately. But it also shows up diabetic changes in the eye; it helps to distinguish between benign and malignant pigment spots; and it's even been used to diagnose a child at risk of getting colon cancer.

Using the Topcon OCT, we also get a photograph of the retina, which is really useful for seeing the changes to blood vessels that occur with raised blood pressure or high cholesterol levels. When you can combine the surface view and the view underneath, you get the complete picture. I recently saw a lady who had quite poor vision, especially in one eye, and cataracts. The OCT revealed a hole in the macula in one eye. But it also showed that a cataract operation in the other eye would restore her vision to normal.

In the 18 months since we've had the OCT, we've done thousands of scans. Most of them have shown normal, healthy eyes. But some have shown problems at a much earlier stage than we would otherwise have detected them. This has meant earlier and therefore more effective treatment, and much sight has been saved. I'm often thankful that we now have this technology.

David Donner