• Reduce the trauma and the time taken for patient rehabilitation.
• The prevailing trend is to perform a mitomycin- C (MMC)-augmented trabeculectomy and trabeculectomy with ologen implants in a trial to decrease bleb failure as a common post- trabeculectomy complication.
• Is to develop a measurement protocol by OCT-A imaging and characterization of the bleb vascularity changes in glaucoma patients before and after surgery.

The main purpose of this project is to compare bleb vascularity changes using optical coherence tomography (OCT-A) between mitomycin- C (MMC)-augmented trabeculectomy and develop trabeculectomy with ologen implants to determine whether bleb vascularity measurements during preoperative and early postoperative periode could act as surrogate parameters to predict surgical outcomes.

Glaucoma often existent in the elderly population. Measuremets of bleb vascularity beginning to become an essential part of the glaucoma specialist's clinical and operative took. As investigators continue to collect data both clinically and in the laboratory, these various imaging modalities will shepherd surgeons into a more precise and predicable era of glaucoma surgeries.

Inclusion Criteria:

• patients older than 18 years of age with primary or secondary open-angle glaucoma.
• Primary OAG (POAG) diagnosed on the basis of IOP measurements more than 21 mmHg, open angle on gonioscopy (Grade 3 or 4 on Schaffer grading system for angle width), glaucomatous visual field defects consistent with glaucomatous optic disc changes.
• PNAG was diagnosed by the presence of narrow or occludable angle on gonioscopy (Grade 2, or 1 on Schaffer grading system for angle width in at least 180° of the total circumference of the angle in primary position without indentation), glaucomatous optic disc changes, visual field defects and IOP more than 21 mmHg

Exclusion Criteria:

• pregnant or lactating female.
• previous intraocular surgery
• one-eyed patients.
• previous ocular trauma.
• uveitis-induced glaucoma, neovascular glaucoma, aphakic/pseudophakic glaucoma
• systemic connective tissue disease and missing more than 3 follow-up visits.
• Trabeculectomy augmented by either MMC or Ologen implant was indicated to study subjects if they had uncontrolled IOP under maximum antiglaucoma medications (3 antiglaucoma drugs) or due to poor socioeconomic status.