Clear-lens extraction has been considered as first-line therapy for primary angle closure glaucoma(PACG) and application of toric intraocular lens (IOLs) leads to better postoperative visual acuity, yet little is known about the prevalence of corneal astigmatism in PACG patients. We intend to make biometry examination for Chinese PACG patients, to obtain keratometry (K) , axial length (AL) and so on, and demographics data will also be recorded. We will study the prevalence of corneal astigmatism before glaucoma surgery in Chinese patients with PACG. Furthermore, differences of corneal astigmatism between primary angle-closure glaucoma and cataract patients will be explored. Finally, the prevalence of corneal astigmatism before glaucoma surgery in Chinese patients with PACG will be portrayed and can be instructive to the IOLs' manufactering.

Biometry examination contains keratometry (K) , axial length (AL), central anterior chamber depth, visual field loss(mean deviation, MD), choroidal thickness(CT), range of goniosynechia, and stage of PACG.

Demographics data contains age, gender, and eye.

Inclusion Criteria:

• Patients who are phakic and aged 40 years or older , and had newly diagnosed primary angle closure with intraocular pressure 30 mm Hg or greater or primary angle-closure glaucoma, will be recruited during preoperative screening at Zhongshan Ophthalmic Center.

Exclusion Criteria:

• Patients with corneal disease, irregular astigmatism, previous corneal or intraocular surgery, or a history of ocular inflammation will be excluded.

Primary angle closure was defi ned as iridotrabecular contact, either appositional or synechial, of at least 180° on gonioscopy, and primary angle-closure glaucoma as reproducible glaucomatous visual fi eld defects, glaucomatous optic neuropathy, or both, and intraocular pressure greater than 21 mm Hg on at least one occasion.