A Clinical Study Comparing the Inflammatory Response of the Ex-Press Mini Shunt to Trabeculectomy

Inclusion Criteria: All subjects must: 1. Be willing and able to provide written Informed Consent. 2. Be able and willing to follow instructions on the use of post- operative medication and likely to complete the entire course of the study. 3. Be male or female of any race at least 18 years of age. 4. Have medically uncontrolled glaucoma for which they have elected to undergo surgery. 5. Diagnosed with primary open angle glaucoma, pigmentary or pseudoexfoliation glaucoma. Exclusion Criteria: No subject may: 1. Have any contraindication to intraocular surgery. 2. Diagnosed with: primary angle closure glaucoma, normal tension glaucoma, secondary glaucoma, neovascular glaucoma. 3. Have any active ocular disease other than glaucoma that would interfere with study parameters (such as: uveitis, ocular infection, or severe dry eye). Subjects with mild chronic blepharitis, age-related macular degeneration and background diabetic retinopathy may be enrolled at the discretion of the investigator. 4. Have laser ALT or SLT within the past 3 months or cataract surgery within the last six months. 5. Require use of ocular NSAID or systemic steroids. 6. Have known allergy or sensitivity to mitomycin C 7. Have corneal abnormalities that would interfere with the ability to obtain an adequate laser flare measurement. 8. Be concurrently enrolled in an investigational drug or device study or participation within the last 30 days in any investigational drug or device study. 9. Be pregnant, nursing, planning a pregnancy, or be of childbearing potential and not using a reliable form of contraception (a woman is considered of childbearing potential unless she is postmenopausal, has had a uterus and/or both ovaries removed, or has had a bilateral tubal ligation). 10. Have a situation or condition that in the investigator's opinion may put the subject at significant risk, may confound the study results, or may interfere significantly with participation in the study.