1. Morphometry and spectral parameter assays: Clinical correlative studies in primary and secondary glaucoma subgroups: This is a volunteer study to obtain volumetric measurements of age-related changes in the ciliary body and individual ciliary muscle components. The study will provide baseline values for treatment monitoring studies of glaucoma therapeutics. There is minimal risk that the ultrasound procedure may reveal an occult ocular disease process, but the probability is very small. Patients will be informed and assisted in obtaining appropriate care if any abnormality is seen.