Intraocular lens dislocation and tube shunt in the posterior chamber: a case report

BACKGROUND: To describe management of a case of intraocular lens (IOL) and capsular bag (CB) dislocation in an eye with an Ahmed glaucoma valve in the posterior chamber. CASE PRESENTATION: A 75-year-old pseudophakic man with open-angle glaucoma and diabetic retinopathy developed neovascular glaucoma. After two intravitreous injections of bevacizumab and panretinal photocoagulation were administered, the new vessels regressed. However, goniosynechiae were observed over 360° of the angle. An Ahmed glaucoma valve model FP7 was implanted with the tube in the posterior chamber with adequate intraocular pressure control. Nineteen years after cataract surgery, when the IOL-CB complex became dislocated, they were sutured transclerally to the sulcus without Ahmed glaucoma valve modification. After a coughing episode, the vitreous pushed the IOL-CB complex forward and the tube was behind the IOL-CB complex. A 25-gauge posterior vitrectomy was performed, and the tube was returned to in front of the optic of the IOL using a forceps tip through a sclerotomy. CONCLUSION: This case suggested that management of IOL-CB dislocation can modify glaucoma shunt function. A complete pars plana vitrectomy may be required in order to reposition the dislocated IOL-CB complex in the presence of a posterior chamber drainage tube implant.