Optical Coherence Tomography (OCT)


Technology in the eye care field is racing ahead at a lightning pace. We now have the ability to diagose many eyes conditions way ahead of conventional techniques, and one of the greatest advances in this area is Optical Coherence Tomography or O.C.T.  O.C.T. is similar in some ways to the results we see when we do an ultrasound on some other part of the body, but rather than ultrasound, O.C.T. uses light. It creates an image of tissues of the retina so we can see down through the cell layers in three dimensions. The best analogy is that of a cake. If we view a cake from the top only we have no idea of the layers underneath that constitute how the cake layers are made and it’s the same with conventional diagnostic techniques. When an eyecare professional looks at the back of your eye they only see the top layer of the cake, they can’t see what is happening below the surface. O.C.T. however changes all that. It gives us a very accurate snapshot in minute detail of the health of the macular area of the retina including the optic nerve head.

Healthy macula scan
This is a scan of a healthy macula. The dark stripes are the shadows of blood vessels.

The scan below is of a patient of ours who has diabetes. It looks quite different to the one above. The diabetic macula oedema can clearly be seen as swelling and sacks of fluid.

OCT scan of diabetic macular oedema
Thiis is an OCT scan of diabetic macular oedema

Fortunately there is now treatment available if the oedema is diagnosed early enough. Diabetics in particular should be having regular eye examinations as they are particularly susceptable to complications.

Posted by Murray O'Brien on September 23, 2013