Abstract
Abstract: :
Purpose: In cicatrizing corneal diseases (chemical burns, ocular cicatricial pemphigoid,Stevens-Johnson syndrome,etc) a keratoprosthesis can be valuable but it is often complicated by severe glaucoma. A glaucoma shunt is effective but the development of an unusually thick capsule around the shunt plate can still leave the pressure unexpectedly high.Theoretically, the intraocular pressure may then be lowered by connecting additional tubing from the shunt plate to a cavity with an epithelial lining where fibrous tissue may not form to block the aqueous flow, i.e., the lacrimal sac or the sinuses. In exploring this hypothesis it must be shown that immediate intraocular infection is not a major problem. Methods: Five patients with keratoprosthesis and Ahmed valve shunt had a silicone tubing placed between the shunt and the lacrimal sac or the ethmoid sinuses. Three of the patients had Stevens-Johnson syndrome, one had ocular cicatricial pemphigoid and one had repeated graft failures. Four of the five patients had uncontrollable glaucoma. The patients were followed for seven, six, three and two months respectively. Results: No infection occurred in any of the patients and the intraocular pressures remained normal. Conclusion: On a short term basis it seems that implanting tubing to divert aqueous humor from a glaucoma shunt (distal to the valve) to the lacrimal sac or ethmoid sinuses will not necessarily result in ocular infection in keratoprosthesis patients. Long-term studies will be necessary to determine the effect of such shunts on the intraocular pressure.