High Frequency Deep Sclerotomy (HFDS) ab Interno a Combination Surgical Intervention Using Cataract Surgery to Lower IOP

Inclusion Criteria: Patients suffering from primary open-angle glaucoma (POAG) inadequately controlled with maximum tolerated medical therapy and who will be treated with cataract surgery. Exclusion Criteria: * One eyed patients * Unwilling or unable to give consent, unwilling to accept randomization, or unable to return for scheduled protocol visits * The presence of extreme narrow angle with complete or partial closure in either eye, except for occludable angles treated with a patent iridectomy * Any abnormality preventing reliable applanation tonometry, any opacity or patient uncooperativeness that would restrict adequate examination of the ocular fundus or anterior chamber of either eye * The risk of visual field or visual acuity worsening as a consequence of participation in the trial, in the investigator's opinion * Any clinically significant, serious, or severe medical or psychiatric condition; any condition that, in the investigator's opinion, would interfere with optimal participation in the study or present a special risk to the patient * Participation in any other investigational study within 30 days prior to baseline visit