Scar Removal

PTK ( Photo Therapeutic Keratectomy ) is a phototherapeutic keratectomy operation performed with an excimer laser. The primary aim of phototherapeutic keratectomy is to reduce scarring. After part of the scar is removed, the cornea relaxes over the following months, which reduces its irregular curvature. Correction of the corneal curvature is undertaken 4 to 6 months later during a second laser operation, wavefront-guided PRK ( Photorefractive Keratectomy ).

If the corneal scar is shallow and small – with opacities extending no deeper than a quarter of the cornea’s thickness – it can be removed in a way that avoids a corneal transplant. The PRK procedure, which smooths and “polishes” the cornea with an excimer laser, is an effective method for superficial corneal opacities and scars. How the operation proceeds:

• the operation takes from a few seconds to a few minutes, is painless and is performed on an outpatient basis

• eye drops are usually sufficient for anaesthesia – the numbing effect lasts for 15-30 minutes after the procedure

• fine particles are removed from the clouded area – the wound heals within around three days For deeper and more extensive scars, the upper layer of the cornea (the epithelium) can first be removed so that the laser can remove the actual clouded parts of the cornea, scars or deposits as accurately as possible. The deeper the corneal tissue is removed, the greater the likelihood that the procedure will leave the patient somewhat long-sighted. As a rule, for every 20 micrometres of tissue removed, the patient shifts by 1 dioptre towards long-sightedness. Thanks to the excimer laser and a special laser profile, the diseased tissue can usually be removed and the cornea gently “polished”, eliminating the need for a transplant. After the operation, a dressing is placed over the eye. A contact lens may also be used for protection. Very rarely, infectious keratitis or ulcers may develop under the contact lens applied as a dressing. Immediate ophthalmological review and treatment are then required.

– more intense pain together with watering, burning, redness of the eye, light sensitivity and a foreign-body sensation in the eye – lasting around 24 hours

• mild eye pain – subsiding after around 4 days

• increased sensitivity of the eye to external stimuli

• noticeable visual disturbances – excessive light sensitivity and glare rings around light sources (the halo effect), which may last up to several months

• somewhat poorer vision at dusk and in the dark – in the first months after the operation NOTE: mild to moderate opacities in the areas where the cornea was treated may appear around a month after the operation, but they will gradually fade over four months and as a rule disappear completely after around two to three years.

Serious complications with PTK are so rare that no statistical probability can even be given, but bear in mind that previous illnesses and a patient’s individual characteristics can influence how often complications occur. In isolated cases the healing process is so vigorous that scarring occurs which may necessitate a further procedure, which in many cases improves the situation. However, this is usually performed several months after the first operation. Post-procedure complications may include side effects of the medication prescribed by the ophthalmologist, for example a hypersensitivity reaction of the ocular surface to the preservatives contained in eye drops, intolerance to antibacterial medication, or a rise in intraocular pressure induced by drops containing cortisone. The corneal scar removal procedure can restore full or partial clarity to a clouded cornea. If the PTK method is used to treat a cracked corneal surface, the upper cell layers of the cornea can generally stabilise to the point that no new cracks appear in the affected area.