Corneal complications following abuse of topical anesthetics

PURPOSE. To describe corneal complications in three patients following abuse of topical anesthetics. MATERIALS AND METHODS. We describe one case with bilateral corneal perforation, another with unilateral corneal perforation and a third case of chronic keratitis following excessive use of topical anesthetics. RESULTS. Two patients continued to instill topical anesthetic drops despite all recommendations to stop. The result was a bilateral corneal perforation in the first case and a large unilateral descemetocele in the second. The third patient who had chronic toxic keratitis discontinued the anesthetic drops and after the appropriate treatment the cornea returned to normal. Corneal grafting and conjunctival flaps were used to seal the corneal perforation but the long-term anatomical and functional results were very poor. CONCLUSIONS. The initial presentation of this rare clinical entity creates difficulties in reaching a correct diagnosis. A presumed acanthamoeba keratitis is the first choice among many similar conditions. Thus abuse of topical ocular anesthetic drops should be included in the differential diagnosis of cases of chronic keratitis as it may masquerade as acanthamoeba keratitis. A current or past history of psychiatric and mental disorders or psychoactive substance abuse is important in the diagnosis. Functional and anatomical results after appropriate treatment are usually poor. Psychiatric counselling is extremely helpful and is in fact mandatory in the management of these patients.