It’s a question that causes hot debate on the internet: Does having large pupils disqualify a person from being a good candidate for LASIK, PRK, or LASEK? You may have heard that when a person has large pupils, they will experience visual disturbances like glare and halos, especially at night, after undergoing these refractive surgeries. Is that necessarily true? And is there a pupil size that is too large for LASIK? To answer, let’s examine the evidence by considering what the latest studies show. We’ll also consider how refractive surgery technology has advanced in recent years.
How the PRK/LASEK/LASIK Laser Works
The original Summit laser applied treatment to a 4mm optical zone without a blend. Since a normal pupil size in adults varies from 2 to 4 mm in diameter in bright light, this optical zone generally provides excellent visual acuity during the day. However, pupil size in adults varies from 4 to 8 mm in the dark, and this was likely associated with nighttime halo and glare complaints in certain patients. In the early days, as a precaution many patients were told they were not a suitable candidate for LASIK or other refractive surgeries because of the laser’s limitations.
While proper screening is still vital for potential refractive surgery candidates, modern lasers now treat larger zones and have a blend that, in many cases, extends out to 9mm making this problem much less significant.
LASIK Pupil Size: What the Studies Show
According to the FDA’s PROWL studies, which specifically asked questions about visual disturbances including glares and halos post-LASIK, “less than 1 percent of patients experienced difficulty performing usual activities following LASIK surgery due to any one symptom.” These results take into consideration feedback from patients with a variety of pupil sizes.
Other studies have dug deeper into whether large pupils affect the outcome of refractive surgery. Here are a few examples and the findings:
- Effect of preoperative pupil size on quality of vision after wavefront-guided LASIK by Annie Chan and Edward E Manche – This study looked at 102 eyes and came to this conclusion: “Twelve months after wavefront-guided LASIK surgery, large pupil size does not positively correlate with any postoperative visual symptoms.”
- Evaluation of the relationship between ablation diameter, pupil size, and visual function with vision-specific quality-of-life measures after laser in situ keratomileusis by Steven Schallhorn, Mitch Brown, Jan Venter, Keith Hettinger, and Stephen Hannan – Nearly 300 patients responded to a questionnaire after LASIK surgery. From their responses, the researchers found that “larger pupil diameter is not significantly associated with postoperative satisfaction and visual function as measured with the RQL.”
- The role of the mesopic pupil on patient-reported outcomes in young patients with myopia 1 month after wavefront-guided LASIK also by Steven Schallhorn, Mitch Brown, Jan Venter, Keith Hettinger, and Stephen Hannan – This study looked at the relationship between low-light pupil size and patient-reported outcomes one month after wavefront-guided LASIK in young patients with myopia. Over 10,000 patients participated in this study. The findings? “Low-light pupil diameter was not predictive of surgery satisfaction, ability to perform activities, or visual symptoms at 1 month postoperatively.”
And the studies don’t stop there. As the American Refractive Surgery Counsel (RSC) affirms, “Data from published studies of modern LASIK techniques fail to demonstrate a relationship between pupil size and the quality of postoperative vision. People with large pupils or thin corneas can safely have LASIK.” The article goes on to cite over a dozen studies that reinforce that assertion.
Clearly, large pupil size is not a disqualifying factor for patients who are interested in clearer vision through refractive surgery, be it PRK, LASEK, or LASIK procedures.
What Conditions Do Affect LASIK Outcomes?
Of course, not everyone is a good candidate for LASIK or other refractive surgeries. Conditions that could disqualify a patient include the following:
- The patient is too young. Generally speaking, LASIK is performed on patients 18 years or older. This is because it takes time for the eyes to mature, and until they do, their vision can change or fluctuate. The eyes need to have reached a stable state, before performing refractive surgery, which brings us to our next point…
- The patient’s prescription is not stable. Even adult patients should have a stable prescription for at least one year prior to the surgery. Certain diseases, or pregnancy and breastfeeding, can cause hormonal fluctuations that can cause a patient’s vision to fluctuate. In these cases, a patient may need to wait before having refractive surgery.
- The patient has a disease that can affect wound healing. Certain conditions, such as autoimmune disease or immunodeficiency states can potentially disqualify a patient from refractive surgery.
- The patient is taking medications that could affect LASIK outcomes. Some medications can affect how a patient’s body heals or can cause their vision to fluctuate, which is a risk factor for refractive surgery.
Of course, every patient and every situation is different, which means the best way to know if you qualify for LASIK, PRK, LASEK or any other kind of eye surgery is to get a thorough examination and discuss your vision goals with an experienced professional. CLEI’s team of experts have decades of experience practicing all forms of refractive surgery. In fact, we pioneered many of them. Thanks to our ample experience, and our extensive testing before surgery, we have been able to help many patients who were told they do not qualify for LASIK successfully undergo the procedure with excellent outcomes. If you truly don’t qualify for LASIK, then we have multiple alternative options to offer you for improved vision and quality of life.
Schedule an appointment with us today to start your journey to improved vision. We cater to individuals who live nearby, as well as long-distance and international patients. If you’ve been told “there’s nothing we can do for you,” then we would love to offer you a second opinion.
