Accumap testing will be performed before and two to three hours after treatment is initiated to lower IOP. In eye that have bilateral treatment, one eye will be assigned randomly to the study. The mean multifocal objective perimetry amplitude will be compared before and after IOP reduction. Also, the mean amplitudes of five circumferential zones will be compared before and after IOP lowering. Visual field testing and HRT testing will be performed before and after treatment as well if possible. Paired t-tests will be performed no pre-and post-treatment mean MOP amplitude values and circumferential zones to determine statistical significance. A second group of patients whose pressures will not be lowered will also be tested with Accumap at baseline and two hours afterwards, in order to examine reproducibility of mean MOP amplitude and mean circumferential amplitude. HVF and HRT testing will also be obtained on thes patients when possible.
