LASIK is normally a very successful surgery. However, there are risks that you should understand.
Surface bruises or redness of the eye may occur, as a result of application of the suction ring, when creating the flap. This is of cosmetic nature only and has no bearing on visual outcome. This will typically resolve in about a week without treatment.
Although exceedingly rare with the IntraLase bladeless LASIK technique, surface irregularities may occur during the treatment. These irregularities (abrasions) more typically occur as a result of the patient’s age, due to a weaker bond between the surface and the underlying tissue. Typically, surface irregularities resolve without side effects. A “bandage” soft contact lens may be applied on the eye overnight to facilitate healing.
A flap imperfection is defined as an improper shape, position or thickness to the flap. Although bladeless IntraLase LASIK has been shown to be safer than the microkeratome technique of flap creation, imperfections in the flap may occur in exceedingly rare circumstances, which prevent proceeding with the laser vision correction portion of the treatment. Various studies indicate that imperfect flaps, interfering with ability to proceed with treatment, are less than 1%. In our experience, this incidence is approximately 1 in a 5,000 patients.
Flap alignment problems can result in visual symptoms described as distortion. Dr. Cassidy will personally reapply the flap at the time of surgery in all patients and re-inspect the flap carefully before the patient is released from our facility. At any LASIK center, the patient should not hesitate to ask, whether their surgeon will be managing their flap from the beginning to the end of the surgery. Various studies indicated that frequency of this event might be approximately 2 to 3 for every 100 cases. In our practice, we observe less than 1 per 1000 incidents of flap alignment disturbance.
The extreme rare case of an infection is considered a serious complication. According to the literature, the incidence of post LASIK infection is about 1 in 5,000.
Our doctors have had one incident of infection, performing over 20,000 refractive procedures. We attribute this low incidence to the fact that our LASIK procedures are performed in our state licensed and accredited outpatient surgery center. Most laser centers only rely on a “laser suite.”
Dr. Cassidy and our team use meticulous surgical techniques with specialized surgical instruments to remove excess fluid from the surface of the eye and to use pure oxygen to dry the flap and “shrink wrap” the flap into proper position which improves flap placement. The surgeons personally monitor patients postoperatively, in order to quickly identify any potential problems. This is how we differentiate ourselves from volume-driven “assembly line” approach LASIK factories.
Another serious but infrequent complication is inflammation under the flap or diffuse lamellar keratitis (DLK). Various studies indicate a frequency as high as 3 to 5%. The treatment is usually successful with frequent instillation of steroid eye drops or re-lifting and irrigating under the flap, if the condition is persistent. We are proud to report our incidents of DLK is less than 1 in 5,000 cases. Treatment with eye drops, only, has been successful 100% of the time with our patients. We have not had to lift a flap yet. None of our patients have lost any quality of vision, as a result of this event. Again, we attribute our low incidence and mild involvement of this side effect to our licensed and accredited surgical center employing a sterile environment, specialized equipment, and our attention to detail to one patient at a time.
Postoperative Flap Alignment Problems
Postoperative flap alignment problems may occur as a result most commonly of patients simply rubbing or bumping their eyes in the immediate postoperative interval. Patients need to take personal responsibility of avoiding risky behavior that could affect their otherwise uneventful recovery. Like any surgical procedure, a sufficient postoperative healing interval is required before returning to normal activities. If a flap is disturbed, the patient will require a trip back to surgery for realignment of the flap.
A condition of progressive corneal weakening referred to as keratoconus may occur with or without laser vision correction and is thought to be genetically predisposed. It has a prevalence in the general population of 1 in 2000.
This condition can sometimes be identified in pre-screening testing for laser vision correction patients by determining the thickness and shape of the cornea. If keratoconus is diagnosed, than laser vision correction is contra indicated. However, keratoconus may occur later, even in the presence of normal testing for corneal thickness and normal corneal shape. The clinical manifestation of keratoconus, referred to as ectasia after laser vision correction, may result in a worsening of vision requiring progressive changes in glasses or contact prescription and may require further corneal surgery. The incidence of this complication is reported to be about 1 in 5,000.
Patients who have a thinner than normal cornea or a steeper or irregular cornea shape may be at higher risk of keratoconus. Those patients that require a higher refractive error correction may be more prone to manifest ectasia. Rather than traditional LASIK with a flap, patients with these findings may be better candidates for other treatment options, such as surface laser known as Photorefractive Keratectomy (PRK) or Intraocular Contact Lens (ICL). With the introduction of the thin flap IntraLase LASIK technique, the thickness and shape of the flap is much more predictable and precise, compared to the traditional microkeratome technique, enabling some patients, who would otherwise not be considered a good candidate for a flap, to now be treated with IntraLase LASIK.
The most common side effect is the need to undergo an “enhancement procedure” for over or under correction of the treatment goal. Various studies indicate as high as 10 to 25% incidence of enhancement, depending on the source. The higher the degree of nearsightedness, farsightedness, or astigmatism, the greater the probability that re-treatment may be needed.
Although we do not discourage more challenging higher treatments, our enhancement rate still remains quite low at approximately 3% for custom LASIK. If enhancement is necessary, we recommend waiting three to six months after the initial treatment, at which time a special technique is used to elevate the previously created flap before application of additional laser is applied for the final correction. The flap is then reapplied and heals back into its natural position much in the same way as the initial treatment.
Dryness of the surface of the eye or dry-eye feeling may occur after LASIK due to what most Ophthalmologist contribute to a diminished blink reflex, due to reduced corneal sensation. These symptoms are usually mild and temporary in nature and usually respond to frequent instillation of artificial tears or inflammatory eye drops. However, there are reports, although exceedingly rare, of continuing severe dry-eye syndrome.
Patients may experience temporary night glare or halos after LASIK. This condition typically occurs in patients who already experience some of these symptoms prior to LASIK. There are reports, although exceedingly rare, of glare, halos, star burst, and double vision symptoms of debilitating nature.
In our experience, it is extremely rare for night glare, halos or diminished night vision to persist. Pre-existing large pupils may contribute to these symptoms. We make special effort to screen patients, pre-op, for these predisposing factors and inform patients of these potential side effects. We will use appropriate treatment options now available to eliminate or reduce night vision symptoms with the latest “true” Wavefront guided VISX CustomVue Excimer laser.
For patients with larger pupils, “true” custom treatment is highly recommended as having distinct advantages over other types of laser treatments. Be cautious with claims that the Wavefront “optimized” Allegretto Wave Laser addresses night vision symptoms to the same level as a “true” Wavefront “guided” system, such as the VISX CustomVue. The Allegretto Wave Laser does not address most higher order aberrations, which often contribute to night vision complaints. Only VISX CustomVue has been shown in clinical trials to substantially reduce the incidence of these symptoms.
Other complications and risk factors can occur and are explained in our standard informed consent session. The above explanation is not intended to explain every possible potential risk but may act as a guide, so you can be an informed potential candidate for LASIK. Patients should realize there are no guaranteed results with surgery, and glasses or contacts may still be necessary after surgery. Although, patients over 45 years of age may require reading glasses, it is extremely rare in our practice that other forms of glasses or contacts will be needed. There is an extremely remote possible risk of vision loss, but Moretsky Cassidy LASIK Vision has never had a patient lose sight as a result of refractive surgery. Good patient compliance certainly improves the outcome of LASIK results. One-on-one patient attention by our doctors enable our patients an opportunity to ask questions and understand the process better, and hence better comply with instructions.