Inclusion Criteria:  Aged 45-80 Diagnosed with advanced PACG: meet with (1) (2) (3) or (1) (2) (4) (1)more than 180-degree synechial closure of anterior chamber angle on gonioscopy and it should cover the nasal and inferior quadrants for surgical purposes; (2) IOP> 21millimeters of mercury (mmHg) with or without anti-glaucoma medication; (3) Significant glaucomatous optic neuropathy [cup-to-disc (C/D) ratio≥0.7, or C/D asymmetry > 0.2, or the rim width at superior and inferior temporal < 0.1 vertical diameters of optic disc); (4) With glaucomatous visual field defects, such as nasal step, arcuate scotoma and paracentral scotoma (on reliable Humphrey analyzer using Swedish interactive threshold algorithm (SITA)-Standard 24-2 or 30-2 algorithm); mead deviation ≤-12dB). Patients without clinically significant cataracts with a visual acuity of more than 0.63 (ETDRS LogMAR), or no cataract surgery indication for next 3 years; Axial length≥ 20mm Patients voluntarily participate in the study with signed informed consent and agreed to follow up according to the study plan.  Exclusion Criteria:  History of intraocular surgery or ocular trauma Concomitant with other types of glaucoma, including: primary open angle glaucoma, various types of secondary glaucoma (secondary angle-closure glaucoma, steroidal glaucoma, secondary angle regression glaucoma, neovascular glaucoma, inflammatory secondary glaucoma, true microophthalmia, pseudoexfoliation syndrome, etc.); The International Standardized Ratio (INR) > 3.0 for patients receiving warfarin or anticoagulant therapy before surgery; People with retinal disease that affects the collection of ocular parameters; Long-term local or systemic use of glucocorticoids; Monophthalmia (corrected visual acuity less than 0.01 in non-study eyes); Complicated with serious systemic diseases; Pregnant or lactating women.