From November 18 to 20, 2022, eyecare practitioners from around the world gathered online for Eyes On 2023, a 3 day educational summit offering up to 9 hours of COPE-accredited CE and CME providing the latest innovations in the ophthalmic industry.
Enjoy this presentation from Justin Schweitzer, OD, FAAO, and Vance Thompson, MD, and don't forget to check out our list of future events!
Please note these videos are provided for review only.
When discussing comprehensive refractive surgery in 2023, we’re discussing more than just surgery on the cornea. The conversation needs to include phakic intraocular lenses (IOLs), lens replacement, and even the option of foregoing surgery in favor of using glasses or contact lenses. Having a meaningful conversation with patients about their options and expectations is paramount to achieving successful surgical outcomes.
Refractive surgery and best-corrected image quality
The refractive surgery we ultimately choose for a patient must be the one that will leave them with the best image quality. We can’t live and die by the Snellen chart; we focus a lot on best-corrected visual acuity (BCVA), but what we need to focus on is best-corrected image quality (BCIQ). One of the best ways to assess a patient’s image quality is to ask them about their vision in low light.
Suppose a patient struggles to see in low light situations, such as driving at night in unfamiliar areas. In that case, they are probably not a good candidate for a corneal refractive procedure, as this would indicate an underlying corneal surface issue.
If the patient feels they still see well under those conditions, that's an indicator that their tear film, epithelium, and stroma are probably healthy, and that they would do well with corneal correction, such as photorefractive keratectomy (PRK), laser assisted in-situ keratomileusis (LASIK), or small excision lenticule extraction (SMILE).
With new technologies, we can now look at a patient’s cornea and identify high-order aberrations and irregularities that we couldn’t have years ago. That being said, the phoropter remains an integral part of assessing a patient’s subjective image quality. If a patient continues to have blur after a refraction that is resolved by adding a gas-permeable lens, then that patient likely has some ocular surface issue that needs to be resolved if they hope to move forward with a corneal refractive procedure. These patients may ultimately be better suited for a lens-based procedure or phakic IOL.
The value of patient education in refractive surgery
Although the lens' accommodative abilities weaken as we age, there are still circumstances where a patient may benefit from pseudo-accommodation. When we remove the lens, even in a patient who is in their mid-50s, we are creating absolute presbyopia, so it’s vital that we have a discussion with that patient about what that means. This is another example of how simple communication with a patient can greatly alter the direction of their refractive surgery.
The most powerful focusing element of the eye is the tear film. Evaluating a patient’s tear film does not have to mean investing in any kind of high-tech machinery. A simple patient questionnaire or corneal staining can easily tell you what you need to know.
Every patient who is a candidate for corneal refractive surgery has to be considered not just based on their vision but their optics, biomechanics, and corneal sensation as well. If all of these parts are not considered, even in the most successful of procedures, you may end up with a disappointed patient.
Photorefractive keratectomy pearls
Each corneal procedure has its strengths and weaknesses. PRK is best suited for patients with low correction, patients who suffer from dry eye, or if there's a concern about map dot dystrophy. There are also occupational considerations; if a patient plays contact sports and there's a risk of damaging a LASIK flap, although rare, that may be enough to opt for PRK over LASIK.
“A happy tear film is the most important part of a successful corneal surgery.”
Post-operatively, there is some discomfort with PRK, and the patient will wear a bandage contact lens for several days. The patient will also experience light sensitivity and tearing that will cause fluctuations in vision. Once the bandage contact lens is removed, the patient may notice a decrease in vision as the epithelium continues to heal, and it could take a month or as many as 4 months before optimal vision is achieved.
It’s important to educate the patient about these facts and be encouraging during the healing process. Delayed epithelial regrowth is a major complication of PRK, and there are clinical ways we can promote faster growth, such as punctal plugs or reducing the use of a steroid, but talking with the patient about their lifestyle can also help improve epithelial growth.
Simply turning off a ceiling fan or wearing a shield or swimmer’s goggles at night can help promote growth. Swimmer’s goggles keep water out, but in the case of a dry eye patient, they keep moisture in and prevent rubbing at night, both of which are valuable for healing.
Comparing LASIK and SMILE procedures
The major reason that SMILE is one of the fastest-growing corneal procedures in the world is that it brings together what we love about PRK (no flap) with what we love about LASIK (faster visual return and no pain). SMILE heals faster and results in fewer dry eye symptoms than LASIK. Significant studies suggest that it is also superior biomechanically, but visually, SMILE and LASIK are comparable postoperatively.
“SMILE requires very exact centering of the laser, whereas LASIK does not, making LASIK a technically easier procedure for the surgeon.”
If the laser isn’t exactly centered when the flap is cut, it can be corrected with LASIK, whereas with SMILE, it cannot. Another benefit of LASIK over SMILE is that if a patient requires topography or wavefront-guided surgery, they must rely on LASIK or PRK, as those procedures are not yet available with SMILE.
When to use phakic IOLs
Phakic IOLs are foldable devices placed between the iris and the natural lens. They bridge the gap between refractive surgery and cataract surgery, maintaining the corneal integrity for patients who may be interested in a multifocal or depth-of-focus lens in the future. One of the drawbacks of phakic IOLs is that patients need to be seen yearly after surgery to monitor the endothelium.
Lens-based procedures for refractive correction
1) Light adjustable lenses
The light adjustable lens (LAL) has silicone polymers and macromers, which are photosensitive, allowing the lens power to be adjusted and customized within the eye. If a refractive change needs to be made, it can be done a month after the initial surgery. Up to three changes can be made before finalizing the lens for the patient. This lens achieves the balance between precise vision and adjustability; however, it is only available as a monofocal lens.
2) Trifocal lenses
There are still halos and glare with a trifocal lens, as with older multifocal lenses. The benefit of a trifocal lies in the continuous vision of near, intermediate, and distance, getting a patient closer to the type of vision they had with a pre-presbyopic eye.
“The ideal trifocal experience is often three steps plus time.”
The first three steps are spending 4 to 6 months optimizing the image quality by first undergoing cataract surgery, then laser enhancement if necessary, and finally, a YAG capsulotomy. The second part is allowing the brain the 6 months needed to get used to its new optical system through neural adaptation. If the patient understands this and is willing to go forward with this journey, they will likely be very satisfied with the outcome.
3) Small aperture lenses
Recently FDA-approved, small aperture lenses will soon be available and will be a powerful tool in refractive cataract surgery in the United States, as it already is in many other places worldwide. These lenses are placed in the non-dominant eye and can achieve significant near vision without compromising distance vision.
Refractive surgery in 2023
Having a checklist of the basic things that need to be remembered and addressed before, during, and after refractive surgery is an excellent way to stay sharp and guarantee quality work.
- Ask every patient about eye rubbing and pillow diving.
- Invest in modern-day diagnostics.
- Approach the diagnosis of dry eye as “guilty until proven innocent.”
- Educate patients on all of their non-surgical and surgical visual options.
- Respect image quality and refractive endpoint.
- Get to know the patient well enough to make the “If I were you” recommendation.
- If you do their best option, do it well; if you don’t do their best option, refer to a specialist.
- Perform quality surgery.
- Finish the refractive job you started with attention to both image quality and refractive goal.
- Take care of your unhappy patients.
You will be left with a very high rate of patient satisfaction if you take the time to learn about your patient (both clinically and in their lifestyle), educate them about their options and what their expectations should be, and make choices that will do the most good for the patient, such as referring them to another physician if the patient’s best option is not your specialty.
