Refractive alternatives to LASIK

ByRolando Toyos, MD

Ophthalmology is undergoing a paradigm shift in how it is viewed and managed. Until recently, many practices were divided between LASIK and general ophthalmology. However, in increasingly more practices, LASIK and general ophthalmology are integrated. Cataract patients request spectacle independence common to LASIK patients. Recent advances in refractive and lens technology allow for many patients to be glasses-free, including senior patients. Because many patients are unsure of their options, it is important for ophthalmologists to learn about patients’ histories and expectations to determine the most appropriate procedures for desired outcomes. An understanding of patient expectations and the availability of various refractive techniques with nonsteroidal anti-inflammatory drugs allows for optimum management of vision correction.

An understanding of patient expectations and the availability of various refractive techniques with NSAIDs allows for optimum management of vision correction.
— Rolando Toyos, MD

LASIK alternatives

Not all patients requesting LASIK are aware of options more suited for their visual needs related to occupation or hobbies. A thorough examination and discussion help determine a patient’s visual needs and expectations. For example, a 40-year-old professional pool player who was myopic requested LASIK. The patient did not mind wearing glasses for distance or reading but wanted to be glasses-free for pool tournaments. Instead of full correction LASIK, the patient received blended intermediate vision correction, tailored to his pool-playing needs. Another example of a special-needs refractive patient was a 28-year-old professional basketball player with a visual acuity of -3 D with mild astigmatism and normal anatomy. He requested LASIK but had previously had four corneal abrasions, orbital fractures and eye trauma. Thus, Epi-LASIK was performed on this patient. Epi-LASIK or contact lenses may be a better treatment option than LASIK for patients with increased susceptibility of eye trauma or flap dislocation due to occupational or hobby-related hazards.

Epi-LASIK

Patients who are unable to have LASIK may be candidates for Epi-LASIK. My colleagues and I presented a study at the 2005 annual meeting of the European Society of Cataract and Refractive Surgeons that compared patients with myopic astigmatism who received bilateral or unilateral LASIK (60 eyes, 36 patients) to patients who received bilateral or unilateral Epi-LASIK (16 eyes, 10 patients).¹ One month postoperatively, better visual acuities were observed in the LASIK arm than in the Epi-LASIK arm. However, it was determined that a greater percentage of Epi-LASIK patients had visual acuities better than 20/20 at 3 months postoperatively compared to LASIK patients. Epi-LASIK patients also had fewer higher-order aberrations 3 months postoperatively than LASIK patients at the same time point. Epi-LASIK patients are counseled to expect visual acuities similar to LASIK 3 months postoperatively.

Epi-LASIK pearls

Epi-LASIK candidates include patients with a high risk of corneal abrasions including professional athletes and military personnel, patients with dry eye and patients with corneas less than 500 µm. Patients diagnosed with dry eye are Epi-LASIK candidates because dry eye can be exacerbated when corneal nerves are severed during flap creation with regular LASIK. Patients with corneas less than 500 µm, or patients whose corneal bed would be less than 270 µm after LASIK, are recommended for Epi-LASIK to reduce chances of corneal ectasia. Thinner corneas have an increased risk for ectasia, but Epi-LASIK requires no flap, so approximately 120 µm of corneal thickness is saved in this technique. Corneal haze is reduced by placing patients on 1,000 mg oral vitamin C for 2 weeks before and 3 months after Epi-LASIK, as well as applying chilled balanced salt solution to the eye before flap formation. Epi-LASIK patients are also placed on oral chondroitin and glucosamine for 3 months following surgery to promote corneal healing. NSAIDs prescribed following Epi-LASIK aid in pain control and may be used postsurgery to reduce overcorrection. Bromfenac sodium often results in better patient compliance than other NSAIDs following Epi-LASIK because it is dosed twice a day.

Uncorrected visual acuity - 3 months postsurgery

Figure. Epi-LASIK yields good visual outcomes in patients who cannot receive LASIK.¹

Figure courtesy of Rolando Toyos, MD.

Intacs pearls

Thorough examination of corneal topographies to rule out forme fruste keratoconus is an important step in preoperative LASIK or Epi-LASIK evaluations. Keratoconic patients are not candidates for LASIK or Epi-LASIK but may be candidates for Intacs (Addition Technology, Des Plaines, Ill.) corneal implants. My colleagues and I presented a study at the 2004 annual meeting of the American Society of Cataract and Refractive Surgeons (ASCRS) demonstrating that Intacs increased visual acuity and decreased higher-order aberrations, astigmatism and corneal steepness.² Patients who receive Intacs often report mild postoperative pain, itching and irritation within 3 weeks of implantation. This discomfort may cause patients to rub their eyes postoperatively, which can lead to anterior displacement of the Intac. Thus, patients are treated with NSAIDs for 4 days postoperatively to reduce discomfort and prevent eye rubbing. Patients with allergies often receive olopatadine hydrochloride ophthalmic solution to prevent rubbing.

LASIK and IOLs

Nowhere in ophthalmology is the paradigm shift in treatment choices more evident than in options for hyperopic and presbyopic patients. Multifocal IOLs have allowed for improved treatment options for these patients. My colleagues and I presented a study comparing conventional myopic LASIK correction to conventional hyperopic LASIK correction at the 2004 annual meeting of the ASCRS.³ We observed that more than 90% of patients receiving myopic correction had visual acuities of 20/25 or better, compared with approximately 50% of patients receiving hyperopic LASIK correction. Thus, conventional LASIK may not be the best corrective option for hyperopic patients. Furthermore, LASIK does not stop the progression of presbyopia. My colleagues and I compared the previously mentioned data to data presented at the 2005 annual meeting of the ASCRS and compared the postoperative results of hyperopic patients who received LASIK to the postoperative results of hyperopic patients who received IOLs.^3,4 More than 75% of hyperopic patients who received IOLs had visual acuities of 20/25 or better. Thus, multifocal IOLs may be a better alternative than LASIK for hyperopic patients. Furthermore, multifocal IOLs are a better alternative to LASIK for hyperopic presbyopic patients because they allow patients to achieve better distance vision while correcting their presbyopia.

Refractive IOL pearls

Posterior capsule opacification can be reduced by using the AquaLase handpiece (Alcon, Fort Worth, Texas) to polish the posterior capsule following natural lens removal.⁵ Development of new handpieces to allow for efficient and safe posterior capsule polishing is underway. Use of NSAIDs postoperatively for 4 to 6 weeks is recommended to reduce the risk of cystoid macular edema (CME). Furthermore, optical coherence tomography is effective in detecting postoperative CME.⁵

Conclusion

Ophthalmologists are evaluating LASIK and other refractive treatment options to achieve optimum outcomes. Ophthalmologists must take advantage of Epi-LASIK, corneal implants and refractive lens exchange to meet patients’ expectations. NSAIDs are also being used with refractive surgery to optimize patient healing and comfort. As studies progress, breakthroughs in refractive surgery and vision correction will continue.

References

Toyos R, Youngerman S, Andrews P. Epi-LASIK vs. Custom Cornea LASIK: comparison of higher order aberrations, visual acuity and patient satisfaction. Paper presented at: XXIII Congress of the European Society of Cataract and Refractive Surgeons; September 13, 2005; Lisbon, Portugal.

Toyos R, et al. Intacs increased visual acuity and decreased higher-order aberrations, astigmatism and corneal steepness. Paper presented at: Annual Meeting of the American Society of Cataract and Refractive Surgeons; 2004; San Diego, Calif.

Toyos R, et al. Conventional myopic LASIK correction vs. conventional hyperopic LASIK correction. Paper presented at: Annual Meeting of the American Society of Cataract and Refractive Surgeons; 2004; San Diego, Calif.

Toyos R, et al. Hyperopic patients who received IOLs. Paper presented at: Annual Meeting of the American Society of Cataract and Refractive Surgeons; 2005; Washington, DC.

Toyos R, Youngerman S. AquaLase versus ultrasound prior to ReSTOR IOL implantation: Clinical and visual outcome analysis. Poster presented at: XXIV Congress of the European Society of Cataract and Refractive Surgeons; September 2006; Lisbon, Portugal.

Discussion

Eric D. Donnenfeld, MD: Do patients with diabetes need more NSAID therapy, before or after cataract surgery, than conventional cataract patients? What are other instances in which ophthalmologists use more NSAIDs in patients who have cataract surgery?

William B. Trattler, MD: Patients with preexisting epiretinal membranes should receive more doses of NSAIDs because they have a membrane pulling on the retina that predisposes them to retinal swelling. Patients who had previous retinal surgery should also receive more NSAIDs because they are at a higher risk of developing postoperative CME. In these patients, I pretreat for at least 1 week before surgery.

Rolando Toyos, MD: Ophthalmologists are using preoperative optical coherence tomography (OCT) on patients who had previous retina surgery. If abnormalities appear on OCT, then those patients receive an NSAID for a longer time.

Donnenfeld: A patient with a history of CME in the first eye and patients who have complicated surgery involving vitreous loss require additional therapy.

Toyos: During cataract surgery, patients with high myopia experience movement in the vitreous and pulling on the retina. Patients with high myopia are treated longer than patients who do not have high myopia.

Donnenfeld: Although no literature exists about myopia and CME, patients with high myopia are at greater risk of developing CME than patients who do not have myopia. Treating them longer than other patients may be advisable.