Typical acute angle-closure glaucoma has several different clinical stages, divided into the preclinical stage, prodromal stage, acute attack stage, intermittent stage, chronic stage, and absolute stage. The acute attack stage is mainly characterized by severe headache, eye pain, photophobia, tearing, and significant deterioration of vision, often reduced to counting fingers or hand motion, and may be accompanied by systemic symptoms such as nausea and vomiting. Physical signs include eyelid edema, mixed congestion, corneal epithelial edema, and the appearance of small droplets under the slit lamp. Patients may complain of rainbow vision, which primarily occurs due to the large number of small vesicles in the swollen corneal epithelium and the spaces between epithelial cells.