"Although the convenience of having surgery on both eyes on the same day is attractive, this practice is riskier than having two separate surgeries." Source: FDA website
Surgeons prefer bilateral simultaneous LASIK because it is easier and cheaper administratively, cutting post-op care in half. In a 2003 survey of American Society of Cataract and Refractive Surgery (ASCRS) members(1), 91% of respondents reported performing only simultaneous bilateral LASIK. However, performing LASIK on both eyes at the same time is not in patients’ best interest.
When one eye is done at a time, patients have the opportunity to assess the result and quality of vision in the treated eye before consenting to surgery on the fellow eye. Patients may not elect surgery in the 2nd eye if there are undesirable effects with the first eye. In effect, bilateral simultaneous LASIK deprives patients of informed consent for the 2nd eye.
As of 2015, about a quarter of Lasik surgeons still use a blade (as opposed to a laser) to create the Lasik flap. Microkeratome blades are FDA-cleared for single use, although surgeons routinely reuse the blade on the 2nd eye of the same patient. Having LASIK performed on one eye at a time ensures a new blade will be used for the 2nd eye. It is reported that the quality of the flap cut is reduced with reuse of blades. This may expose patients to an increased risk of complications in the second eye. Tissues remnants left on the blade from the first eye may be dragged into the interface of the second eye.
Complications can affect both eyes if treated simultaneously. Bilateral simultaneous LASIK places patients at risk of vision loss in both eyes.
(1) Leaming DV. Practice styles and preferences of ASCRS members--2003 survey. J Cataract Refract Surg. 2004 Apr;30(4):892-900.
LASIK injury reported to FDA: Patient refused treatment in the second eye due to complications with the first eye.
"I had lasik surgery on my left eye only despite my ophthalmologist's urging that i do both eyes. I had read of the possibility that i would see an aura around lights at night after surgery and did not want to take the chance that would happen on both eyes. I had it done on my eye with the worse vision, 14 diopters. After it was done my vision in that eye was about 1 diopter. It progressed to 3. 5 diopters fairly rapidly and is now at 6. 5 diopters. My complaint is that i read in an ophthalmology text book about six months after the surgery that surgery was not recommended for people with vision of 8 diopters or worse and also that it was not recommended for people of my age. I had the surgery done at a med ctr and the physician should have known this info, but he did not inform me even though i did ask the questions."
Simultaneous bilateral surgery violates the principles of informed consent.
Klaus D. Teichmann, MD:
"The editorial by a journal editor was overdue. I consider it particularly appropriate that simultaneous bilateral laser in situ keratomileusis (LASIK) is subjected to serious questioning. One can only marvel at the naive trust by patients in modern medicine and in their surgeons and the similarly naive convictions of surgeons that simultaneous bilateral LASIK is what the patients need.
It is not purely a safety issue; simultaneous bilateral surgery violates the principles of informed consent. Nobody can deny that experience with the first eye will render the patient better informed for consenting to the procedure being performed on the second eye. Simultaneous bilateral surgery deprives the patient of the possibility of gaining a better refracative outcome in the second eye and of judging the visual benefit of the surgery by comparing the operated eye +/- residual spectacle or contact lens correction with the corrected unoperated eye. Finally, simultaneous bilateral LASIK preempts a possible decision by the patient to choose another type of refractive surgery for his/her second eye, such as photorefractive keratectomy, intracorneal ring segments, or a phakic intraocular lens, or to postpone surgery on the second eye until better procedures become available if the result of LASIK on the first eye proves unsatisfactory. He/she may not have to wait very long."
Source: J Cataract Refract Surg, Volume 26, Number 10 Vol. 26, October 2000.
James J. Salz, MD on bilateral simultaneous LASIK
"In his 22 years of practice, he has never performed bilateral simultaneous RK, PRK, LASIK, clear lens extraction or cataract surgery because he is convinced that it is not in the patient’s best interest to do so. In fact, his refusal to perform simultaneous bilateral LASIK has earned him a reputation for bucking this LASIK trend.
As he states on his Website, http://www.drsalz.com, his decision not to do bilateral simultaneous LASIK comes down to a personal philosophy that the patient’s well-being should outweigh patient and surgeon convenience and any financial considerations for patients, surgeons and laser centers.
While the risk of infection is low in LASIK, Dr. Salz noted, it is not zero. To begin with, the technique itself is not completely sterile. Unlike cataract surgery, it is not performed in a hospital operating room with its required stringent sterility standards; in addition, the LASIK device cannot be completely sterilized because of the motor and cord.
Even if the risk of infection is only 1 in 5,000 with LASIK, given the potential risk of infection in both eyes with a bilateral approach, the risk is not justified, Dr. Salz said. Moreover, “The risk of simultaneous infection is indeed real, despite all the glowing statistics reported in the literature,” he said, citing the following incidents:
In a one-year period, Dr. Salz examined three patients for second opinions who had bilateral complications following LASIK. All three missed several weeks of work because of a combination of diffuse lamellar keratitis, epithelial ingrowth and epithelial abrasions. (He has since seen a fourth such patient.) Had the LASIK been performed unilaterally, these patients would have been able to function with a contact lens in the operated eye during treatment for DLK.
Lawrence Spivack, MD, a refractive surgeon in Denver, has reported DLK with temporary interface haze in 22 eyes following LASIK, most of which were bilateral cases.1 While the haze eventually cleared up, Dr. Salz questioned the wisdom of putting both eyes at risk for haze since the etiology and exact incidence is unknown.
At an Argentine Society of Ophthalmology meeting, Ricardo A. Dodds, MD, reported bilateral retinal detachments on the first postoperative day following bilateral LASIK.
There have now been two epidemics of mycobacterium infections following simultaneous LASIK. One, in Los Angeles, reported by N. S. Chandra et al., involved four patients and seven eyes.2 A second series occurred in Georgia and involved more than 20 patients.
Another argument to consider focuses on patient satisfaction after LASIK is performed. This is particularly an issue in patients with relatively low refractive errors who have the option of wearing contact lenses in the untreated eye.
“I have had several patients who had their first eye corrected with LASIK and found that the quality did not compare favorably to the vision they achieved with a contact lens on the untreated eye,” Dr. Salz said. “They could make the comparison because we performed the procedure unilaterally. And many of these patients chose not to do the second eye. While they are happy they did the first eye, they are glad they didn’t do the second eye. This patient choice is taken away with simultaneous bilateral LASIK surgery.”
Source: EyeNet Magazine, June 2002. Link to full text