infectious keratitis following excimer laser refractive surgery

infectious keratitis occurs rarely after laser refractive surgery, however the high volume of these procedures and young patient age render the prevention, diagnosis and treatment of this complication of utmost importance. early onset infectious keratitis is usually caused by gram positive bacteria while late onset cases are due to other microorganisms such as atypical mycobacteria, nocardia asteroides and fungi. fortified topical antibiotics, selected based on smear and culture results, are the mainstay of therapy. in post-lasik cases, flap lifting and irrigation, and scraping and culture of the ablated bed must be performed; the flap must be amputated for diagnostic and therapeutic purposes when it is frankly necrotic. underlying risk factors such as blepharitis and dry eye must be recognized and adequately treated prior to surgery. strict attention to instrument and surgical field sterility, use of therapeutic bandage contact lenses with high oxygen transmissibility for a maximum period of 72 hours, and prophylactic broad-spectrum topical antibiotics decrease the incidence of this major sight-threatening complication.