Assessment of the optic disc to measure neuroprotection.

In early glaucoma, axonal loss and optic disc change occur in the absence of detectable changes in psychophysical measurements, such as those obtained from standard automated perimetry. Accurate assessment of the anatomy of the optic disc is therefore necessary to document change. The measurement of optic disc topography with scanning laser ophthalmoscopy has been shown to be accurate, reproducible, diagnostically valid, and an accurate reflection of the underlying anatomic status of the optic disc and retinal nerve fibre layer. Validated techniques have been developed to detect change over time in the surface topography of the optic disc. Ultimately, real-time in vivo analysis of the health of retinal ganglion cells should provide the best method of assessing the advisability and adequacy of treatment and the potential value of neuroprotective therapies.