Visual Recovery

Most patients notice an improvement in their vision immediately upon completion of their surgery. By the next day vision is often dramatically improved. However, patients should understand that, while fast visual recovery characterizes the operation, it can take several months before some patients achieve their final vision after LASIK. Several studies^1-2 demonstrate that the vision of a number of patients continued to improve up to six months post-operatively. During that time, patients may experience slight fluctuations in vision throughout the day. These symptoms generally diminish with time.

Crispness of Vision

For some patients, vision after LASIK matches the sharpness of vision they had with glasses or contact lenses before LASIK. However, many patients notice that 20/20 vision after LASIK can be different from 20/20 vision with contact lenses before LASIK, especially gas permeable contact lenses. The images seen through eyes treated by LASIK are often described as not being as "crisp" as those seen through glasses. This condition, referred to in ophthalmic literature as "loss of contrast sensitivity," may not affect your acuity as it is measured on an eye chart, but it can be noticeable in your daily life as a slight loss of sharpness.

The majority of patients do adjust to this change; however some do have difficulty in the first few months following surgery. Fortunately, these symptoms often dissipate within the first six months of surgery. Several published scientific papers have measured patients' pre-operative and post-operative contrast sensitivity, and nearly all have reported that it returns to pre-operative levels within the first six months.^3-7

Dry Eyes

Some patients experience dry eyes post-operatively. The symptoms can vary widely - from being relatively asymptomatic, to intermittent dryness at certain times during the day, to feeling the typical dry sensation much or all of the day, sometimes accompanies by blurry vision or an increase in glare and halos. When the dry eye is treated, those symptoms diminish.

Clinical dry eye is comparatively easy to diagnose and the great majority of patients respond well to treatment options ranging from use of preservative-free eye drops to insertion of punctal plugs, depending on the severity of the case. For almost all patients, dry eye symptoms gradually subside over the first few weeks or months after LASIK surgery. If you suspect that you may have post-operative dry eye, you should contact your doctor's office for an evaluation.

Glare/Halos/Starbursts

Many LASIK patients notice a temporary decreased in night vision with symptoms that include glare, halos, and starbursts. The experience of the phenomena can range from mild to severe. We provide detailed information regarding the incidence of these symptoms in our Quality of Vision section.

These symptoms usually subside within by six weeks or so for the vast majority of patients who experience them. However, some will continue to experience them for a greater length of time.

There are several potential causes of decreased night vision. The most common is the normal mild swelling of the LASIK flap, which resolves within a few weeks of surgery. Many researchers believe that patients who have pupils that exceed the ablation zone may be more likely to experience decreased night or low-light vision following LASIK than the general population. Another cause is incomplete correction of the nearsightedness, farsightedness or astigmatism. Clinical dry eye can also contribute to the experience of glare and halos. Rarely the cause is mild irregularities that the LASIK surgery produces in the shape of the cornea.

Depending upon the cause, those patients who experience significant, persistent glare, halos or starbursts have several treatment options. Enhancement procedures may be an option, but not everyone is eligible for an additional procedure. Eligibility for enhancements depends on a number of factors that a doctor must evaluate. For some patients, prescription eye drops to prevent dilation of the pupil at night to reduce the symptoms of decreased night vision may be an option. However, this pharmaceutical approach is not successful for all people, and it also can represent a significant expense over time. Diagnosis and treatment of clinical dry eye may alleviate many of the symptoms. Toric contact lenses may be prescribed for those who have astigmatism. Future advances in laser technology offer great promise.

Overcorrection, Undercorrection & Regression

Nearsighted patients who experience an overcorrection will become farsighted and will notice immediately that they can no longer see near objects as well. Conversely those who have been undercorrected will notice that objects in a distance are still not perfectly clear.

Farsighted patients who experience an overcorrection will become nearsighted and will notice immediately that they can no longer see objects at a distance clearly. Those who have been undercorrected will notice that near objects are still not totally in focus.

If an over or undercorrection has occurred, the ophthalmologist will discuss your treatment options. Generally, surgeons prefer to wait approximately 3-6 months to perform an enhancement to ensure that the final vision has been achieved. As that point, either a hyperopia or myopia LASIK procedure will be performed to correct the residual error, if the patient and doctor believe it is appropriate.

Conventionally, regression is defined as a shift in initial visual outcome. In this situation, the sharpness of vision that occurs soon after surgery diminishes as the eye regains a small amount of its original nearsightedness, farsightedness, or astigmatism. Regression can occur quickly, within the first few weeks after surgery, but it also can occur slowly over time. Patients who experience regression will notice their vision changing progressively (not a fluctuation during the day). Typically, the ophthalmologist will evaluate the regression to determine its cause and review treatment options with the patient. Typically, an enhancement procedure can be performed to correct the residual error, just as is done to treat an undercorrection or overcorrection.

DLK

As we mention in our Risk & Complications section, diffuse lamellar keratitis (DLK) is a unique and relatively rare post-operative condition following LASIK. Non-severe forms have been estimated in 1% of cases; severe cases comprise only about 1 in 5,000 surgeries.⁸
Patients should understand that at the early stages of the condition, they most likely will not experience symptoms they would be able to discern, and only upon examination by a doctor could this condition be detected. When caught early, the inflammation associated with DLK is easy to treat. Patients should be aware, however, that while approximately 80% of the condition will clear up within the first 24 to 48 hours, it could take several weeks until the condition completely subsides.
We emphasize that this condition can be treated without significant visual loss when it is detected and treated early. Therefore it is imperative that all patients maintain their surgeon's recommended post-operative follow-up examination schedule.
Patients should carefully review their immediate post-operative expectations with their ophthalmologist prior to the surgery. They should discuss the follow up schedule and all post-surgical instructions. Then, if you notice something about your vision that deviates from your doctor's expectations, you should notify his/her office immediately.

Other Potential Complications

We emphasize that all patients should notify their doctor at once if they have any questions about their recovery after surgery. Only a doctor who has performed an examination of your eyes and has a complete medical history can accurately determine if your situation is within normal limits or requires care.