The authors describe a prospective study of 40 participants (20 healthy and 20 with glaucoma) enrolled to compare the measurements of the optic nerve head (ONH) parameters given by time domain (TD) and spectral domain (SD) optical coherence tomography (OCT). Visual field examinations were also carried out using SITA standard 24-2. Cirrus HD-OCT ONH imaging was then carried out using the optic disc cube. A second operator then performed Stratus OCT ONH imaging a few minutes later consisting of six radial scans on the ONH. In both healthy and glaucoma subjects the authors found that the Cirrus HD-OCT provided higher CDR measurements than Stratus. Differences were also seen with measurements of the disc and rim areas.