Patient Management
Why Wait?
Our patients want same-day, bilateral LASIK. Here are some compelling reasons to give them what they want.
By Richard J. Duffey, M.D., Mobile, Ala.

Few would argue with the statement that LASIK has emerged as the dominant refractive surgery for correcting nearsightedness, farsightedness and astigmatism worldwide. However, some debate does continue over whether we should perform the surgery unilaterally -- one eye at a time -- or bilaterally, in one operating room (OR) visit.

Most refractive surgeons are offering bilateral LASIK, (See "Standard of Care,"), and more patients are requesting it. Here, we'll look at why the standard of care has shifted.

The intraocular distinction

Ophthalmology does have a longstanding tradition of operating on one eye at a time as a conservative approach to patient care. A closer inspection of that tradition, however, demonstrates that its applicability is primarily with intraocular surgery.

Certainly, the risk of endophthalmitis from cataract surgery can result in devastating visual loss. So few would challenge the merits of operating on one eye and waiting to make sure that endophthalmitis isn't a reasonable possibility before performing surgery on the second eye. However, strabismus and blepharoplasty surgery and other extraocular procedures have been performed bilaterally for decades. The apparent distinction is extraocular vs. intraocular, with the extraocular procedures presenting almost negligible endophthalmitis risks.

We also have the argument that if we operate on two eyes, we have two times the risk of complications. This is a reasonable argument to consider in the risk-to-benefit ratio.

LASIK-specific complications

But let's take a closer look at complications specific to LASIK and evaluate them in a unilateral vs. bilateral scenario.

• Corneal infection. This is a relatively rare complication, probably occurring in less than one in several thousand surgeries. It generally takes 3 to 7 days to diagnose bacterial keratitis following LASIK. That means a surgeon must wait at least 1 week between eyes to be relatively sure that infection hasn't occurred in one eye before embarking on the second.
• Diffuse lamellar keratitis. DLK is typically diagnosed on the first postoperative day and requires immediate diagnosis, treatment and surveillance. This is perhaps the best argument against bilateral, same-day surgery because DLK can be diagnosed so early, allowing the second surgery to be done relatively quickly after the first, once DLK has been eliminated as a potential complication in the first eye.
  Interestingly, in my practice, the incidence of surgical intervention in DLK is approximately one in 1,200 surgeries. Furthermore, DLK tends to be unilateral or at least more severe in one eye, rarely requiring bilateral intervention whether the surgeries are done on the same day or separated by a defined period of time. In other words, if DLK develops in one eye, the likelihood that it will develop in the second eye and require surgical intervention, whether the surgery is done on the same day or days or weeks later, remains low.
• Epithelial ingrowth. The incidence of epithelial ingrowth requiring surgical intervention in my practice is also approximately one in 1,200 surgeries. Epithelial ingrowth is typically diagnosed at the 1-month post-op visit, and often requires several more weeks of follow-up before surgical needs are well defined. Again, to eliminate this complication in one eye before the second eye surgery would require weeks, if not months, between surgeries for our LASIK patients.
• Irregular astigmatism, central and paracentral islands, and slow wound healing. These are potential complications in all LASIK patients. The occurrence in my practice is in 1% of surgeries. Most are unilateral and seldom diagnosed until 2 to 4 weeks after surgery. Any presence earlier than that is often related to flap edema and is transient. If visual acuity is excellent 1 day post-op, the likelihood of irregular astigmatism is extremely low, allowing second-eye as soon as possible.
• Flap complications. The one common flap complication that requires excellent judgment on bilateral vs. unilateral surgery is an epithelial problem such as an epithelial slide, tear or defect. If central in nature, where it will affect visual acuity in the early postoperative period, I recommend postponing the second eye surgery until the first eye has adequate vision for the patient to function normally. Sometimes that may be only several days, but can be several weeks. This is especially true if a large defect occurs, for example, in a hyperopic female patient with a large flap and dry eyes and/or map-dot-fingerprint dystrophy for an underlying condition.
  The most common postoperative flap complication is a slipped flap or significant striae formation that limits visual acuity. A slipped flap diagnosis is typically made on the first postoperative day and necessitates surgical intervention. In my practice (where more than 95% of patients choose to have bilateral, same-day surgery), I have yet to see bilateral slipped flaps on the first postoperative day in the past 5 years. Flap striae that require surgical intervention are also typically unilateral. It often takes weeks before a surgeon can make a definitive decision on surgicalintervention.

Bilateral benefits

With those points in mind, we can look at the advantages of bilateral, same-day LASIK surgery:

• Saving time. LASIK patients tend to be active, time-conscious people. By performing bilateral, same-day surgery we can reduce the OR visits and postoperative follow-up visits by half, providing a considerable time savings for these patients.
• Limiting patient discomfort. The most common complaint that I received when I performed strictly unilateral surgery was about the healing period and the anisometropia between the eye surgeries. Bilateral surgery eliminates this.
  Although more than 95% of patients return to normal activities within a day of their surgery, they still require a significant period for general wound healing with complaints of dry eyes, scratchiness and light sensitivity. Patients appreciate the opportunity to go through this extended healing process in both eyes simultaneously.
• Added safety. I believe there's also an added safety feature to bilateral LASIK. If the first surgery went perfectly, you minimize the odds of a blade-related complication in the second eye when you use the original blade in the same OR setting.

Patient/surgeon preferences

When deciding whether to perform unilateral or bilateral surgery, we must consider the preferences of both patient and surgeon. I always let the patient choose which option he feels is better for his schedule, personality, etc. If a patient chooses unilateral surgery, I don't have the right to override that decision. However, if a patient chooses bilateral simultaneous surgery, I reserve the right to do only unilateral surgery because of pre-existing problems or intraoperative complications requiring a delay on the second eye.

In 1996, the first year I performed LASIK, I did unilateral surgery on all patients and waited 2 weeks before operating on the second eye. That time decreased to 1 week and then 4 days. By mid-1997, the waiting period was 1 to 2 days.

At that time, I had bilateral simultaneous LASIK performed on my own eyes and was able to witness firsthand the advantages of going through the procedure just once with half the amount of follow-up time and no anisometropia. From that point, I began providing bilateral simultaneous surgery for my patients who chose this option, the percentage of which steadily rose from approximately 70% to the current number of more than 95%.

A timely choice

Simultaneous bilateral LASIK, when combined with the proper precautions and appropriate informed consent, is an excellent option for our LASIK patients. It really has become the documented standard of care in the United States. 

Dr. Duffey is a cornea, refractive and cataract specialist at Premier Medical Eye Group in Mobile, Ala.