The primary focus of this study is to assess intraocular pressure and complication rates between patients who receive mitomycin-C using a sponge versus no-sponge.

Inclusion Criteria:

1. Men or women aged 18 years and older at screening.
2. Diagnosis of chronic angle-closure glaucoma or open-angle glaucoma, phakic or pseudophakic, with visual field or optic disc changes characteristic of glaucoma.
3. Suitable candidate for trabeculectomy with Ex-PRESS glaucoma filtration device with MMC in the superonasal quadrant in the study eye which the physician deems as medically necessary.
4. Capable and willing to provide consent

Exclusion Criteria:

1. Unable or unwilling to provide consent

2. Any previous ocular surgeries in the study eye preventing placement of the trabeculectomy with Ex-PRESS glaucoma filtration device with mitomycin-C in the superonasal quadrant

3. Any previous glaucoma drainage devices in the study eye

4. Any abnormality other than glaucoma in the study eye that could affect applanation tonometry.

5. Presence or history of any abnormality or disorder that could interfere with the study procedure or prevent the successful completion of the study.

6. Presence or history of uveitis within 10 years or any other ocular infection or inflammation within 14 days before day 1.

7. Any significant unstable cardiovascular, hepatic, renal, respiratory, gastrointestinal, endocrine, immunologic, dermatologic, hematologic, neurologic, or psychiatric disease.

8. Known Pregnancy or Breastfeeding

   Physical and Laboratory Findings

9. Conjunctival scarring precluding a superonasal implantation location.

10. Vitreous in the anterior chamber.

11. Abnormality preventing reliable applanation tonometry in the study eye.