The two researchers, Baris Sonmez of the David Geffen School of Medicine at the University of California at Los Angeles and Robert K. Maloney of the Maloney Vision Institute, call the condition, which has been reported since 1998, central toxic keratopathy. Their paper appeared in the American Journal of Ophthalmology.
In their study, the eye specialists reviewed the medical history and clinical photographs of 14 of their patients who had the disorder. Of the 23 eyes that were involved, 19 had been treated with LASIK (short for laser in situ keratomileusis), and four with a similar procedure, PRK, or photorefractive keratotomy.
The cornea clouding generally started three to six days after the surgery. It was noticed only in the cornea’s dead center, where the greatest laser energy was received. The clouding negatively affected the eyes’ focus, making them hyperopic. But the opacification abnormality cleared up in two to 18 months.
The researchers warned doctors to steer away from treating the condition with corticosteroids. Since the clouding isn’t an inflammation, they said, using these drugs would increase the risk of glaucoma, cataracts and vision loss.
After seven patients’ corneas cleared, they underwent successful LASIK surgeries – and experienced no further cornea clouding. The fact this didn’t recur, Sonmez and Maloney said, suggests that “some external inciting factor is necessary” for the condition to develop. The two researchers hypothesize that it is “a toxic reaction to some substance that undergoes photoactivation by the laser.”