Two Cases of Malignant Glaucoma after Ahmed Valve Implantation

Abstract

Purpose: To report two cases of malignant glaucoma after Ahmed valve implantation.Case summary: (Case 1) A 76-year-old female with angle closure glaucoma in the right eye underwent Ahmed valve implantation. To reduce the risk of corneal endothelial failure, the tube tip was located in the sulcus. Eight days after surgery, surgical iridectomy was performed due to intraocular pressure elevation and a shallow anterior chamber. Three weeks later, vitrectomy was performed due to intraocular pressure elevation with a shallow anterior chamber. Recurrent intraocular pressure elevation was resolved after tip reposition into the vitreous cavity. (Case 2) A 93-year-old female with pseudoexfoliation glaucoma underwent Ahmed valve implantation in the left eye. Five days after surgery, the intraocular pressure increased with a shallow anterior chamber; the remnant cortex and prolapsed vitreous body were present in the anterior chamber. She underwent anterior chamber washing and surgical iridectomy; however, the increase in intraocular pressure with a shallow anterior chamber worsened after 1 month; thus, anterior vitrectomy was performed.Conclusions: Malignant glaucoma after Ahmed valve implantation is considered very rare. However, if risk factors such as short axial length, zonular weakness, old age, or female gender are present, as in these cases, there may be an increased risk of malignant glaucoma developing after Ahmed valve implantation.