Background: thirty patients underwent full ophthalmic examination, including a review of medical history, best-corrected visual acuity, slit-lamp biomicroscopy, intraocular pressure measurement, gonioscopy, dilated fundoscopic examination, automated perimetry, and OCT at 1 month and after 6 months. Objectives: the aim of the study was to assess RNFL thickness, ONH clinically and by OCT and correlate RNFL thickness by OCT with visual fields by standard automated perimetry in glaucoma patients, highlighting the usefulness of OCT in glaucoma patients where diagnosis by standard means were not confirmatory. Patients and methods: All patients were scanned using SD-OCT (RS-3000; Nidek) after dilation with 1% tropicamide eye drop and the images were acquired by a single operator. Also, standard automated perimetry was conducted using the SITA 24-2 of the Humphrey Field Analyzer program (Carl Zeiss Meditec) with a Goldmann size III stimulus on a 31.5-apostilb background. Results: There was a statistically significant difference between patients at 1 month and after 6 months as regards OCT (RNFL), on comparison between the four quadrants at 1 month the mean of the inferior quadrant was > superior > temporal > nasal respectively. After 6 months the mean of the four quadrants as well as the total RNFL thickness decreased but only the decrease in the temporal quadrant and total RNFL thickness was statistically significant (P=0.003, P=0.044 respectively). Conclusion: An OCT would be significantly informative early in the disease course to diagnose a preperimetric glaucoma, to confirm on a visual field, and to follow up glaucoma progression.