Phototherapeutic keratectomy, or PTK, is a surgical procedure used to treat diseases of the corneal surface. PTK seeks to make the surface of the cornea clearer and smoother. It is considered a medical procedure, and, as such, is often covered by insurance. It is different from photorefractive keractectomy (PRK) or laser-assisted sub-epithelial keractectomy (LASIK), both of which seek to improve vision and decrease the patient's need for corrective lenses. Phototherapeutic keratectomy can, however, improve vision problems caused by corneal surface diseases, such as scarring, corneal dystrophies, or recurrent epithelial erosion syndrome.
PTK is an alternative approach to traditional therapies for diseases of the corneal surface. Prior to the advent of laser eye surgery, treatments relied upon special eye lubrication, manual corneal resurfacing, corneal transplants, and contact lens bandages. Laser therapies such as PTK allow surgeons to correct abnormalities on the surface of the cornea more effectively.
Before undergoing the phototherapeutic keratectomy procedure, patients are usually sedated. The eye area is typically cleaned and sterilized, and anesthetic eye drops are administered to control pain during the procedure. The eyelids are held open by an eyelid holder during the surgery.
The procedure itself takes only a moment or two to perform. Patients are generally asked to focus on a target light while the laser does its work. Afterward, the surgeon typically examines the cornea to verify the results.
Patients may need to shield their eyes with dark glasses for up to three days following phototherapeutic keratectomy. Changes in vision are common during the first five days of recovery. Many patients will experience discomfort as the eye heals. Medicated eye drops, oral pain medications and contact lens bandages can be used during the recovery period. Most patients will be able to resume work and other normal activities within three to five days, though, in some, vision changes can last up to six months.
Patients undergoing phototherapeutic keratectomy can usually expect an improvement in vision over the long term. The effects are normally permanent. Side effects usually go away quickly. Some patients may experience continued sensitivity to light and glares, and may see halos around lights, indefinitely.
Most patients will need a new eyeglass or contact lens prescription, and some may become longsighted after treatment. Alternatives to PTK involve corneal transplants. Surgeons may also scrape the cornea to smooth it by hand.