Prospective Evaluation of the Efficacy of Pascal Laser Iridotomy and Pascal Laser Peripheral Iridoplasty: A Pilot Study

Objective: The main objective of this study is to evaluate the efficacy of Pascal Laser Iridotomy and Pascal Laser Peripheral Iridoplasty in lowering intraocular pressure and opening up the angles in patients with narrow angles, primary angle closure and primary angle closure glaucoma.

The specific objectives are to evaluate the pain and inflammation associated with the procedure and its possible adverse effects on the lens and corneal endothelium.

Study Design: Prospective, interventional case series Study Population: Healthy males and females with appositional angle closure aged 21 y/o and above Methods: Potential participants are evaluated by a glaucoma specialist in National University Hospital. If they are identified as having appositional angle closure they are invited to participate in the study and assigned to either iridotomy or iridoplasty depending on the mechanism of angle closure present. Pupil block for Pascal Laser Iridotomy and plateau iris and angle crowding for Pascal Laser Peripheral Iridoplasty. If they agree to participate they will undergo visual acuity, slit lamp examination, intraocular pressure determination by Goldmann Applanation Tonometry, gonioscopy, optic nerve head evaluation by indirect ophthalmoscopy and lens evaluation by LOCS III opacity grading system. Humphrey visual field examination using 24-2 SITA standard algorithm and stereodisc photos will be obtained if not done within the past 12 months. Anterior segment OCT and laser flare meter will also be performed prior to the procedure. Enrolled patients will be divided into 2 groups. The first group will be assigned to Pascal Laser Iridotomy. The primary mechanism of angle closure in this group is pupillary block. The second group will be assigned to Pascal Laser Peripheral Iridoplasty. This group has non-pupil bock mechanisms which include plateau iris or angle crowding. After the laser procedure, follow-up examinations will be done 1 hr post laser, 1 week, 1 month, 3 months and 6 months.

Outcome Measures: The primary outcome measures are the intraocular pressure difference pre and post laser and the opening of angles. Secondary outcome measures are pain and inflammation associated with laser procedure, lens and corneal endothelial changes.