Multi-center, prospective, randomized, controlled clinical trial to compare selective laser trabeculoplasty (SLT) and Argon laser trabeculoplasty (ALT) in pseudoexfoliation glaucoma and ocular hypertension patients. IOP will be recorded, at baseline, 6 weeks, 6 months and 1 year after the laser procedure.

This study derives from a clinical observation that laser treated eyed with PXF glaucoma may have a similar long-term response rates when either ALT or SLT is performed. Some authors have considered that there is a risk of IOP elevation in the immediate post laser period with ALT or SLT as a complication to be related to denser angle pigmentation (20,48). (46) No long-term analysis comparing response rates of both laser treatments in these types of patients has been done.

Primary objective is to determine which laser therapy has more IOP lowering effect as primary or adjunctive treatment in eyes diagnosed with ocular hypertension and glaucoma associated to PXF. Response rates will be compared between groups at long-term.

Secondary objective is to determine the relationship between the type of laser therapy performed and angle pigmentation, number of applications, and amount of energy used with age, number and type of medication used post laser and phakic status.

Inclusion Criteria:

• Only patients with clinical evidence of unilateral or bilateral open angle pseudoexfoliation ocular hypertension (IOP > 22mmHg) or glaucoma (Evidence on Humphrey 30-2 or Goldmann of nerve fiber layer damage) with uncontrolled IOP, over 18 years of age, and are willing to participate in the study will be included. If increased IOP is bilateral then the worst eye will be treated.

Exclusion Criteria:

• Patients will be excluded if they have evidence of any glaucoma other than pseudoexfoliative open angle, if the trabecular meshwork cannot be seen in 360 degrees, if they had previous laser therapy ALT or SLT, if they have advanced visual field defect (split fixation or a scotoma within 10 degrees fixation), taking any systemic or topical steroids, have had any previous ocular surgery (glaucoma or cataract extraction included) or laser within the previous six months, if they are monocular patients, if they have any corneal disease precluding the angle evaluation and treatment, or if they had ocular trauma.