Both surgeries use lasers to cut flaps in the cornea to alter its shape.

LASEK, laser-assisted subepithelial keratectomy, cuts only the outside surface of the cornea. LASIK, laser in situ keratomileusis, makes a deeper incision, Webmd.com said Friday.

To find out which procedure was better, researchers compared 122 eyes treated with LASIK to 122 eyes treated with LASEK.

"Both procedures seem safe, effective and predictable," researcher Dimitri Azar said.

Eyes treated with LASEK had slightly better vision, but Azar said the difference was too small for patients to notice.

The findings were reported in the December issue of the American Journal of Ophthalmology.