Shallow anterior chamber is the most common complication early after glaucoma filtration surgery. Overfiltration is a common cause, mostly caused by improperly made scleral flap, oversized scleral fistula, poorly sealed flap and oversized filter bubble. 1, scleral flap is too thin, if the scleral flap is too thin is bound to contract significantly, plus the scleral flap suture is not tight, and the filtration is too strong. The scleral flap thickness should not be less than one-third of the scleral thickness during the operation. 2, the trabecular resection length is equal to the scleral flap, which actually causes the trabecular incision to correspond with the incision at both ends of the scleral flap, which is equal to the atrial water entering directly into the subconjunctiva, and it is easy to form a strong filtration, and the incidence of shallow anterior chamber increases significantly when the length of the trabecular resection is too long during surgery. Such shallow anterior chamber is usually treated conservatively with good results, and no special treatment is needed for shallow grade I anterior chamber. For cases of hyperfiltration, in addition to dilating the pupil, the lid surface of the corresponding part of the filter bubble can be covered with a small, poke-shaped pillow and gently wrapped with a bandage under pressure. If the inflammatory response in the anterior chamber is significant, subconjunctival injection of dexamethasone 2.5 mg is given once or twice/d. Instead of compressing the follicle, collagen-masked soft contact lenses can be worn. Alternatively, autologous blood can be used for intravesicular injection. Usually the atrium can be formed before 3 to 5 days of treatment. If conservative treatment is ineffective, anterior chamber reconstruction should generally be performed after 5 to 7 days of aggressive combination therapy for shallow grade II anterior chamber and 1 to 2 days for shallow grade III anterior chamber without improvement. The amount of anterior chamber air injection is appropriate to separate the cornea from the iris and the peripheral anterior chamber is formed. 3, conjunctival flap leakage, the conjunctival flap is the outer protective tissue of the filter bubble, despite the scleral flap decompression, but there is still some atrial water drainage to the subconjunctiva. Poor healing of conjunctival flap, needle eye, rupture, conjunctival incision with fascial inlay and poor fixation of conjunctival flap during surgery will make atrial water lose the protection of filtration barrier, resulting in atrial water leakage and shallow anterior chamber. Atrial water leakage also affects the healing of the conjunctival wound. Patients on combined antimetabolic drugs should be given high priority. If postoperative hypotony occurs in the shallow anterior chamber (usually with a flattened filtration bubble), the conjunctiva of the filtration zone should first be carefully examined under slit lamp for the presence of notch leakage. Fluorescein examination shows that there is a stream at the site of leakage. Preventive treatment, do not do subconjunctival injection in the filtration area, the scleral flap suture end should be buried under the tissue, with the dome as the base conjunctival flap should be firmly stretched and tightened from the front cover to about 0.5 to 1.0 mm before the corneal edge incision, in order to prevent postoperative conjunctival flap recession, scleral flap incision exposure and leakage from the anterior edge of the filtration bubble. Good conjunctival flap suturing is closely related to the success rate of surgery. For small leaks, local use of epidermal growth factor and other drugs to promote and protect epithelial tissues and pressure bandages can heal. For larger leaks like waterfall and scleral flap edge exposure due to conjunctival flap regression, surgical exploration should be actively taken to find the leaking site and close sutures in layers. 4, choroidal detachment, ciliary body choroidal detachment can also cause low intraocular pressure shallow anterior chamber, after conservative treatment, most choroidal detachment with the extension of time, the gradual increase in intraocular pressure can be self-relieved, if the choroidal detachment area is larger shallow anterior chamber continued and expanded shallow II or III degree no anterior chamber, and the need for surgical drainage of choroidal fluid and combined with anterior chamber gas injection are good results, this surgical method can be repeated several times This procedure can be repeated several times. At the end of the surgery, BSS fluid is injected into the anterior chamber through the puncture port to deepen the anterior chamber and raise the IOP to prevent postoperative hypotony. 5, malignant glaucoma, malignant glaucoma caused by shallow anterior chamber is often accompanied by increased intraocular pressure. The reason is that the ciliary muscle contraction sends ciliary ring block, the crystal suspensory ligament relaxes, the ciliary body and crystal equatorial part of the adhesion, atrial water retention behind the crystal, the crystal and iris are moving forward, the iris appears highly inflated, the anterior chamber generally becomes shallow atrial water discharge is obstructed, at this time can only inflow to the rear. This causes the vitreous to detach and move forward, so that the crystal pushes forward even more, the anterior chamber becomes more shallow, and the atrial angle closes again to form a vicious circle, so it is ciliary ring blocked closed angle glaucoma. For malignant glaucoma, early emergency measures should be taken to reduce the pressure at the back of the eye and break the ciliary ring block. At the same time, pharmacological treatment including hyperosmolar agents, carbonic anhydrase inhibitors and ciliary muscle paralyzing agents should be taken and supplemented with corticosteroids to reduce the inflammatory response and ciliary edema. If medication is ineffective after 4 to 5 days, surgical treatment may be changed. Surgical treatment includes vitreous puncture for fluid release and anterior chamber insufflation, or, if ineffective, crystal removal or vitrectomy.