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• Certain systemic medications (e.g., isotretinoin, amiodarone, sumatriptan,
levonorgestrel implants, colchicine)
• Under 21 years of age (FDA labeling should be consulted for each laser)

Surface Ablation Techniques
Photorefractive Keratectomy
In PRK, the central corneal epithelium is removed and the excimer laser is used to ablate

Bowman’s membrane and superficial corneal stroma over the entrance pupil.
Laser Epithelial Keratomileusis and Epi-LASIK

Laser epithelial keratomileusis (LASEK) is a modification of PRK that attempts to preserve
the epithelium. After alcohol is applied to the corneal epithelium, an epithelial trephine
and spatula are used sequentially to score, loosen, and roll up the epithelium, which
remains attached at a nasal or superior hinge. Photoablation is then performed, and the

epithelium is unrolled back over the central corneal stroma. A bandage contact lens is used
for several days until the surface re-epithelializes.

An alternative surface ablation procedure to LASEK is epi-LASIK. Instead of using alcohol to
loosen the epithelium, an epikeratome is used to dissect an epithelial sheet from
Bowman’s membrane. The epikeratome is similar in design to a mechanical microkeratome
used for LASIK. Instead of using an oscillating sharp blade to incise the cornea beneath
Bowman’s membrane, the epikeratome uses a blunt oscillating separator that moves
across the cornea held under high pressure with a suction ring. This separator lifts a sheet

of epithelium from Bowman’s membrane. The laser ablation is then performed and the
epithelial sheet is either replaced or discarded. Visual recovery and discomfort with LASEK
and epi-LASIK are similar to PRK and are prolonged relative to LASIK.

Alternatives for patients who are Lasik Rejects:
For eyes with THIN CORNEA
· PRK / LASEK / EPI-LASIK
· SBK (Sub Bowman’s Keratomileusis)
· Intra corneal Rings
· Phakic IOL (ICL)
For eyes with ABNORMAL SHAPE
· Intra corneal Rings (INTACS, Kera rings )
· Phakic IOL

Phakic IOLs

Phakic IOLs fall into three broad categories:
• Anterior chamber angle-fixated lenses, originally introduced by Baikoff and Joly
• Anterior chamber iris-fixated lens, introduced by Fechner and Worst

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