Adaptive Optics OCT Evaluation of Rhopressa's Effects on the Retinal Ganglion Cells in Glaucoma Patients

Inclusion Criteria: * All subjects will be 18 years of age or older * Subjects must be diagnosed with open-angle glaucoma and have had an eye exam within the past year * Subjects with glaucoma will have structural (optic nerve and retinal nerve fiber layer) and functional (visual field testing) defects consistent with the diagnosis of glaucoma * Subjects will have a corrected acuity of 20/50 or better and be able to fixate * Naïve to medication subjects or post washout IOP between 18 and 34 mmHg * Spherical equivalent from +3 diopters to -6 diopters, with a cylinder of \<-3 diopters * Subject is willing and able to comply with the protocol requirements and to remain in the study for its full duration, including all scheduled visits and follow-up assessments Exclusion Criteria: * Subjects with a known intolerance to netarsudil ophthalmic solution * Subjects with a known intolerance to, or contraindication for, timolol maleate * Any subject whom the investigator determines to be at unacceptable risk for the washout or believes is unlikely to complete the study * Subjects with retinal disease or optic neuropathies other than glaucoma that, in the opinion of the investigator, could confound the study assessments or outcome * Female subjects who are pregnant, breastfeeding, or of childbearing age who are not sterile or using an acceptable method of contraception during the study