Trabeculectomy Versus Peripheral Iridectomy Plus Goniotomy in Advanced PACG

Who May Qualify: 1. Age 45-80 years. 2. Eyes diagnosed with advanced PACG who meet following criteria a, b, and c; or a, b, and d: 1. PAS: ≥180° range, including nasal and inferior quadrants; 2. IOP \>21 mmHg with or without anti-glaucoma medications (the medications include the maximally tolerated medications), taken with the Goldmann applanation tonometer; 3. Glaucomatous optic neuropathy (cup-to-disc \[C/D\] ratio ≥0.7, C/D asymmetry \>0.2, or rim width at the superior and inferior temporal areas \<0.1 of the vertical diameters of the optic disc); 4. Glaucomatous visual field defects (nasal step, arcuate scotoma, and paracentral scotoma on a reliable Humphrey analyzer and a mean deviation of ≤-12 dB). 3. No or mild cataracts and uncorrected visual acuity of ≥0.63 (Early Treatment Diabetic Retinopathy Study chart); 4. Axial length of ≥20 mm. Who Should NOT Join This Trial: 1. History of ocular surgery or trauma. 2. Retinal disease that influences the collection of ocular parameters or other types of glaucoma, including open-angle glaucoma, secondary angle-closure glaucoma, steroidal glaucoma, angle recession glaucoma, neovascular glaucoma, nanophthalmos, and pseudoexfoliation syndrome. 3. Monophthalmia (best-corrected visual acuity of \<0.01 in the non-study eye). 4. An International Standardized Ratio of \>3.0, for patients receiving warfarin or anticoagulant therapy before surgery. 5. Patients with serious systemic diseases. 6. Pregnant or lactating women. If both eyes are eligible for the study, the eye with the worse visual field or optic nerve will be included. Always talk to your doctor about whether this trial is right for you.