There are very few inherent risks and complications involved in LVC surgery. In spite of our very best efforts and the best technology, there will be some results that are less than ideal. You must make a decision based upon the best information available whether or not the potential benefits of your contemplated surgery outweigh the risks. Although it is not possible to list every potential risk or complication that may result from the procedure, many of them are described below:
Halos / Starbursts: Some patients will notice glare, halos or starbursts around objects at night or in dim-light conditions. Patients who notice these effects may need to wear glasses to drive at night. For the vast majority, these symptoms are temporary. However, others will continue to experience them for several months or longer. During your pre-operative evaluation, we will determine whether or not you are at high risk for seeing long-term halos. These side effects tend to be less noticeable the closer you get to the ideal correction of your refractive error. Note that CustomLASIK reduces the frequency of glare, halos or starbursts problems following treatment and results in clearer, crisper vision compared to treatments performed by conventional LASIK.
Dry eyes: Increased dryness of the eyes is a common, but generally temporary, complication arising from LASIK, CustomLASIK, IntraLase, or PRK. It typically lasts for several months, though some patients may experience dryness for a longer period of time. It is important to use lubricating drops frequently. If the eyes remain dry for prolonged period, there are other drops or techniques that can help. Patients who have dry eyes prior to the procedure are likely to experience dry eyes after the procedure.
Infection: All eye surgeries carry with them the possibility of infection. This is an extremely rare occurrence, with a 1 in 10,000 treated eyes. Fortunately, as the laser vision correction techniques have developed over the years, firmly established protocols now exist which dramatically minimize the risk of infection. Most infections respond well to antibiotic treatment.
Diffuse Lamellar Keratitis (DLK) or “Sands of the Sahara”: Some patients develop an inflammatory reaction between the flap and the corneal bed, called Diffuse Lamellar Keratitis (DLK) or “Sands of the Sahara.” Patients with DLK may not show any symptoms at all or may experience blurred vision and tearing. DLK can generally be treated with eye drops and rarely results in any permanent impairment of vision.
Retinal detachment: Although retinal detachment is not usually considered a specific complication of laser vision correction surgery, it is at least a possibility. Even without any surgical intervention, myopic patients are always at risk for retinal detachment and LASIK may not alter this risk.
Anesthesia or drug reactions: As with all types of surgery, there is a possibility of complications due to anesthesia, drug reactions, or other factors which may involve other parts of your body. The patient must inform the doctor if they have ever had a reaction to any kind of anesthesia.
Corneal scarring: There are corneal irregularities which can rarely occur. The worst case scenario could be corneal scarring. The risk of corneal haze or scarring is more in PRK than in LASIK.
Equipment malfunction: The microkeratome, IntraLase and Excimer lasers have proven to be very elegant, very dependable devices for creating the corneal flap and reshaping the cornea. Nevertheless, we are working on the cornea which is about 0.6mm thick, and as with any device, the microkeratome, IntraLase, and Excimer laser are not perfect. In spite of out best efforts, there are times when they produce a less than ideal result. We will not begin your procedure unless our equipments are functioning properly. Additionally, we might have to stop at the safest possible point if a malfunction should develop.
Surgical team: The less the experience of the surgeon and team, the greater is the risk. But even with the best available equipment and the most experienced surgeons, complications can and do occur. The only way to avoid all risks of surgery is not to have the surgery done at all. As a generality, the more serious the risk, the less likely it is to occur.
Vascular occlusion: When the suction ring is applied to the eye to create a corneal flap, the pressure inside the eye increases significantly and most patients notice either a dimming or a complete loss of light in the eye. As the suction ring is removed, the vision is restored within a few seconds. There is a less than 1 in 1,000,000 probability that when the suction ring interrupts the blood supply to the eye, permanent damage to the retina and loss of vision can result. Note that unlike microkeratome, IntraLaseemploys a suction ring that uses low vacuum.
Increased pressure in the eye: The drugs used during the first week after surgery, on rare occasions, may cause increased pressure in the eye. This raised pressure needs to be closely monitored and may require additional topical and/or oral medications. It is important for you to return to NeoVision Eye Center for scheduled follow-up visits to monitor your eye pressure in order to modify the medication schedule as needed.
Eyelid droop: The eyelids have a natural tendency to droop with age. The eyelid speculum that is used in the procedure may hasten this process.
Corneal ectasia: A certain minimum amount of corneal tissue must remain under the flap after the laser has achieved tissue removal. The amount of remaining tissue relates directly to the long-term stability of the cornea. Less than optimum remaining cornea may result in bulging, called ectasia. This problem can be avoided by precise pre-operative measurements and creating an optimum corneal flap during surgery.
Improper corneal flap: The corneal flap may be of improper or irregular thickness or incompletely cut. Such problems may require that the procedure be stopped until the surgeon can safely cut a new flap. There is also a small risk that the hinge of the flap may be cut from the cornea (also known as a “free flap”). In most instances of “free flap” the surgeon can still perform the laser treatment. This detached flap is repositioned and covered with a bandage contact lens to promote healing. Note that the IntraLase laser may avoid partial and “buttonholed” flaps, corneal wrinkles, and flaps that are too thick.
Increased light sensitivity and vision fluctuations: Patients’ eye may become extremely sensitive to light and glare after the procedure. Visual acuity may also fluctuate. These conditions are generally temporary and usually go away within 1-3 months
Epithelial defects: The epithelium in some eyes is only loosely attached to the corneal surface. Such eyes are at increased risk for epithelial erosions or defects, especially as the microkeratome passes over the corneal surface. In some cases, this risk is identified before surgery and the patients are advised accordingly. There are, however, occasional patients where there are no pre-operative clues. In addition, older patients are more likely to have occult areas of this weakened skin. Note that the IntraLase laser may better avoid some of the epithelial irregularities and sloughing.
Epithelial ingrowth: Epithelial cells can appear as either “isolated pockets or nests” under the LASIK flap. This may result due to improper healing at the edge of the flap. Most of these are fairly easy to successfully eliminate. Note that the IntraLase flap follows the curvature of the cornea and produces a flap with vertical edges, unlike the edges left by a microkeratome. This difference in flap architecture may reduce the chance of corneal epithelial ingrowth.
Under-correction or over-correction
: The healing response of the eye occasionally counteracts the precisely calibrated removal of tissue by laser. While the treatment of your refractive error is designed to completely neutralize your refractive error (unless otherwise agreed upon with your surgeon) this treatment is based on an average eye’s healing response. If your eye heals differently from the “average”, this may result in an over- or under-correction. A patient’s tolerance for under-correction or over-correction varies. In majority of instances, the over- or under-correction can be corrected with glasses, contact lenses, or additional surgery.
It is important that you understand this possible outcome and accept it as one of the risks of surgery. If this should occur, you will probably be disappointed with your result. Under- or over-corrections are actually the most common undesirable result or complication of surgery. Significant over-corrections occur about 1% of the time.
Re-treatment or enhancements: The vast majority of patients require only one refractive treatment. Due to each individual’s prescription level and unique physiology, however, an additional treatment or enhancement may be required. The additional procedure can involve all of the risks and side effects as discussed before for the primary procedure. As always, this risk should be weighed against the expected or desired benefit. The patient must generally wait at least three to six months after the first treatment and must have adequate corneal tissue and stable vision. Results cannot be predetermined or guaranteed.