SMILE Eye Surgery Halo Effect

Understanding the Halo Effect After SMILE

Halo rings appear around lights when your eye’s optics shift during healing. SMILE reshapes the cornea through a small incision, removing a lenticule to correct nearsightedness and astigmatism. While SMILE avoids a large flap, corneal tissue still changes, and as your cornea heals, minor swelling and surface irregularities can cause light to scatter unevenly, creating visible halos.

Halos are most noticeable at night, under streetlights or car headlights. They tend to be more prominent in dim settings when pupils dilate. About 5% of SMILE patients experience noticeable halos soon after surgery.

How SMILE Surgery Changes Light Refraction

SMILE uses a femtosecond laser to carve a thin tissue layer within the cornea, removing a lenticule to reshape the corneal curvature. This allows light to focus properly on the retina. While SMILE doesn’t create a flap like LASIK, the process still causes slight edema (swelling) and remodeling in the cornea, leading to changes in how light bends. These changes result in halos, which fade as the cornea heals.

Typical Timeline: When Halos Peak and Fade

Most SMILE patients notice halos most intensely during the first two weeks after surgery. After this period, the halos gradually decrease in intensity:

• Week 1–2: Peak halo intensity, especially in low light
• Month 1: Noticeable reduction; small halos may remain
• Month 3: Most patients report clear night vision
• Month 6: Final corneal stabilization; halos nearly gone

Managing Halos During the Healing Phase

To ease halos while your eyes heal, follow these steps:

• Wear polarized sunglasses outdoors to reduce glare and light scatter.
• Avoid driving at night until halos fade. Use anti-glare glasses if necessary.
• Use preservative-free artificial tears to prevent dry eye, which can worsen halos.
• Follow post-op instructions for prescription eye drops to control inflammation and support tissue repair.
• Install night lights at home to limit sudden exposure to bright headlights.

Identifying Risk Factors for Persistent Halos

While most halos fade, certain factors can make them more likely or longer-lasting:

• Large pupils: Larger pupils can extend beyond the optical zone, causing light scatter.
• High prescription: Higher diopter corrections can remove more corneal tissue, leading to more irregularities.
• Dry eye syndrome: Dry eyes create uneven surface curvature, exacerbating halos.
• Night driving demands: Frequent low-light driving makes halos more noticeable even as they fade.

Preventive Tips for a Smooth Recovery

You can reduce the chance of severe halos by preparing your eyes before surgery and caring for them well afterward:

• Treat dry eyes in advance with prescription drops or punctual plugs.
• Avoid contact lenses before surgery to let your cornea regain its natural shape.
• Use anti-inflammatory medications as directed to minimize early swelling.
• Maintain follow-up visits for quick issue detection and correction.
• Limit caffeine and screen time, as they can worsen dryness and slow healing.