Risk factors of shallow anterior chamber other than hypotony after ahmed glaucoma valve implant

PURPOSE: To find the risk factors of shallow anterior chamber following hypotony after Ahmed glaucoma valve implant. METHOD: The retrospective study was carried out with patients who had postoperative intraocular pressure 5'mm Hg or below at 2 consecutive visits after Ahmed glaucoma valve implant surgery. They were divided into 2 groups by the depth of anterior chamber and various factors were compared including age, sex, diabetes, hypertension, glaucoma type, previous intraocular surgery, preoperative visual acuity, refractive error, lens status, corneal thickness, endothelial cell count, axial length, preoperative intraocular pressure, number of preoperative glaucoma medications, use of carbonic anhydrase inhibitor, gonioscopic examination results, and use of ligation suture. RESULTS: Groups with younger age (P=0.041), myopia (P=0.003), and fewer previous intraocular surgeries (P=0.000) showed higher risk and partial ligation of the tube (P=0.000) showed protective effect of shallow anterior chamber by hypotony after Ahmed valve implant. CONCLUSIONS: When performing Ahmed glaucoma valve implant surgery in patients with more risk factors of shallow anterior chamber, preventive procedures and proper management can improve the success rate of the implant and reduce its complications.