Psychophysical measurement of glaucomatous damage

Within the past twenty years, a number of new psychophysical test procedure s have been adapted for use in perimetry and visual field testing. These pr ocedures are designed to measure the functional properties of different typ es of retinal ganglion cell subpopulations. Although many of these new proc edures exhibit better performance characteristics than standard automated p erimetry, no single test procedure appears to be decidedly superior to all others. Comparison of multiple functions in patients with early glaucomatou s damage suggests that visual function losses are not selective for specifi c retinal ganglion cell subpopulations in all patients. For evaluation of t he efficacy of neuroprotective agents in glaucoma, one of the challenges fa cing the development of new psychophysical tests is to be able to distingui sh visual function losses that are due to ganglion cell drop-out ("dead" ce lls) from those that are due to malfunctioning retinal nerve fibers ("sick" cells). (C) 2001 by Elsevier Science Inc. All rights reserved.