Prospective, single-arm, single-center, non-randomized, non-comparative study including naïve patients attending our center diagnosed with glaucoma, who have been recommended treatment with direct selective laser trabeculoplasty (DSLT) by their ophthalmologist and who are under no hypotensive medication. DSLT treatment will be performed with the Voyager DSLT system; it will consist of the application of 120 laser pulses of preset 3 ns and a preset 400 μm spot size, with an energy of 1.8 mJ delivered to the limbus through a full 360 degrees. The study will evaluate the effect of DSLT on intraocular pressure (IOP). Baseline IOP will be the IOP measured with Goldman applanation tonometry by the investigator on the day of treatment, prior to the application of DSLT. Patients will be seen one week (±2 days), one month (±7 days), three months (±15 days), six months (±30 days) and 12 months (±40 days) after DSLT treatment. In each of these visits, the attending ophthalmologist will measure IOP with Goldmann applanation tonometry and record the presence of any relevant ocular signs and query patients regarding potential adverse events. The study´s main end-point will be percentage reduction in IOP six months after DSLT compared to baseline.