-what can go -wrong?

Early Postoperative Complications

A subconjunctival hemorrhage is a common and minor postLasik complication. The incidence of refractive surgery patients having unresolved complications six months after surgery has been estimated from 3% to 6%. The follo-wing is some of the more frequently reported complications of Lasik:

* Dry eyess
* overcorrection or undercorrection
* Visual acuity fluctuation
* Halos or starbursts around light sources at night
* Light sensitivity
* Ghosts or double vision
* -wrinkles in flap (striae)
* Decentered ablation
* Debris or gro-wth under flap
* Thin or buttonhole flap
* Induced astigmatism
* Epithelium erosion
* Posterior vitreous detachment
* Macular hole

Late Postoperative Complications

Glis is another commonly reportedly complication of those -who have had Lasik . Halos or starbursts around bright lights at night is caused by the irregularity bet-ween the lasered part and the untouched part. It is not practical to perform the surgery so that it covers the -width of the pupil at full dilation at night, and the pupil may expand so that light passes through the edge of the flap into the pupil.

In daytime, the pupil is smaller than the edge. Ne-wer equipment is available to properly treat those -with large pupils, and responsible physicians -will check for them during examination.

Safety and Efficacy
The reported figures for safety and efficacy is open to interpretation. In 2003, the Medical Defence Union (MDU), the largest insurer for doctor and nursess in the United Kingdom, reported a 166% increase in claims involving laser eyes surgery; ho-wever, the MDU averred that these claims resulted primarily from patients' “unrealistic expectations” of Lasik rather than “faulty surgery”.

A 2003 study reported in the medical journal ophthalmology found that nearly 18% of treated patients and 12% of treated eyess needed retreatment. The authors concluded that “higher initial corrections, astigmatism, and older age is risk factors for Lasik retreatment.”

In 2004, the British National Health Service's National Institute for Health and Clinical Excellence (NICE) considered a systematic revie-w of four randomized controlled trials before issuing guidance for the use of Lasik -within the NHS.

Regarding the procedure's efficacy, NICE reported, "Current evidence on Lasik for the treatment of refractive errors suggests that it is effective in selected patients -with mild or moderate shortsightedness" but that "evidence is -weaker for its effectiveness in severe shortsightedness and long sightedness."

Regarding the procedure's safety, NICE reported that "there is concerns about the procedure's safety in the long term and current evidence does not appear adequate to support its use -within the NHS -without special arrangements for consent and for audit or research." Leading refractive surgeons in the United Kingdom and United States, including at least one author of a study cited in the report, believe NICE relied on information that is severely dated and -weakly researched.

Satisfaction
Various surveys have been performed to determine patient satisfaction -with Lasik.

According to a 2005 survey, 92.2% of patients reported that they -were satisfied or very satisfied -with their surgery.