[Glaucoma after extremely severe chemical and thermal eye burns. Surgical possibilities]

Late secondary glaucomas after severe chemical or thermal eye burns are associated with diagnostic and surgical difficulties. Routine filtering surgery (trabeculectomy) has a low success rate. In these eyes aqueous shunt implantation and cyclophotocoagulation are alternative procedures.

In our retrospective study, the records of 12 patients with 14 severe eye burns (grade IV) were analyzed. Nine eyes were treated with an aqueous shunt device (six von Denffer and three Ahmed implants). Diode laser cyclophotocoagulation (Iris Medical Instruments) was performed in five eyes. The mean time interval between surgery and accident was 88.3 months (aqueous shunt) and 32.8 months (cyclophotocoagulation).

The mean follow-up was 45 +/- 36 months (von Denffer implant), 38 +/- 5 months (Ahmed implant), and 11 +/- 8 months (cyclophotocoagulation). Intraocular pressure (IOP) was reduced from 39 +/- 7 to 23 +/- 6 (von Denffer implants) and from 38 +/- 3 to 8 +/- 10 (Ahmed implants). Mean IOP before treatment with cyclophotocoagulation was 33 +/- 8 and 18 +/- 2 after treatment. Systemic carbonic anhydrase inhibitors were stopped in all patients. Visual acuity deteriorated in five of nine eyes treated with aqueous shunt devices and was unchanged or better in all eyes treated with cyclophotocoagulation. Multiple re-operations were necessary after aqueous shunt implantation. Severe complications leading to failure in these eyes were encapsulated bleb in four eyes, expulsive hemorrhage in one eye, and phthisis in one eye. Cyclophotocoagulation was repeated in two eyes. Severe complications were not observed.

IOP reduction was effective and comparable in both procedures. Because of the high incidence of severe complications after shunt surgery, we prefer cyclophotocoagulation for the treatment of intractable glaucoma after severe eye burns.