Imaging Glaucoma.

Optical coherence tomography (OCT) is changing the way glaucoma is studied and diagnosed. Glaucoma damages retinal ganglion cell (RGC) axons at the optic disc, and the resulting retrograde degeneration destroys the RGC bodies. OCT allows for a noninvasive measurement of both retinal nerve fiber (RNF) and RGC layer thickness. In this article, OCT techniques are described for studying the thinning of these layers due to glaucoma. We have learned that there is more damage to the macula (central ±8 deg) than previously thought, and a simple anatomical model provides an explanation for this finding. Further, OCT technology has led to improved understanding of the relationship between RGC and RNF layer loss and behavioral data. Finally, another imaging technique, adaptive optics, has allowed a better visualization and understanding of details that are often difficult or impossible to see with current OCT technology.