Consider pros, cons of SMILE enhancement options
Key takeaways:
- Surgeons need to know about available options in case enhancement is needed after SMILE.
- Surface ablation does not require flap creation, and off-label “cap-to-flap” technique has quick recovery.
ORLANDO —The need for enhancement procedures after SMILE is rare, but surgeons need to consider the advantages and disadvantages of each option, according to a speaker here.
In the literature, enhancement rates after SMILE (Zeiss) are under 4%, Nandini Venkateswaran, MD, said at Refractive Surgery Subspecialty Day at the American Academy of Ophthalmology meeting. Risk factors for higher rates of enhancement include older age and higher preoperative manifest refraction. Most enhancements occur in the first year after the initial SMILE procedure and typically occur for undercorrection of refractive error.
“What are our enhancement options if we fall into that scenario?” Venkateswaran, of Massachusetts Eye and Ear and Harvard Medical School, said. “Can we perform SMILE again? In theory, I suppose you could create a lenticule anterior or posterior to the original SMILE interface, but there’s only one case reported in the literature. If you think about the range of refractive errors that you are typically enhancing, at least in the United States, very low degrees of myopia or even hyperopia are not going to be within the treatment range for SMILE surgery.”
According to Venkateswaran, surface ablation can be a “wonderful option” for enhancement because it does not require flap creation. It is a tissue-sparing straightforward procedure but may have a slower and more painful recovery period with an increased risk for corneal haze, she said.
Venkateswaran recommended epithelial thickness mapping to help determine whether a patient is a good candidate for surface ablation.
“You want to ensure you have nice, homogenous epithelium to ensure epithelial stability,” she said. “Intraoperatively, as you’re removing the epithelium, depending upon the diameter you’re removing, you want to be mindful of not disrupting that SMILE incision.”
Another option is thin-flap LASIK of 80 µm to 90 µm, leaving around 30 µm to 40 µm of stromal bed for excimer ablation, but risks include tissue bridge perforation into the cap interface, buttonholing and gas bubble breakthrough. Alternatively, thick-flap LASIK entails creating a flap of 120 µm or larger. While this procedure bypasses the area of lenticule creation and extraction, “this does require substantial stromal thickness for the retention of corneal biomechanic stability,” according to Venkateswaran.
She also highlighted the CIRCLE technique, built into the software of the VisuMax laser (Zeiss) and available to surgeons outside the U.S., and the off-label “cap-to-flap” technique to convert a SMILE cap into a LASIK flap. Research shows that the cap-to-flap technique has better results compared with LASIK flap re-lifts and surface ablation, with one study outside the U.S. demonstrating comparable vision outcomes between CIRCLE and surface ablation in 24 eyes but faster vision recovery within 1 week in eyes that underwent CIRCLE.
“We just want to ensure the patient is OK to have a flap created,” Venkateswaran said.
Sources/Disclosures
Source:
Venkateswaran N. Enhancement options after small incision lenticule extraction (SMILE) surgery. Presented at: American Academy of Ophthalmology meeting; Oct. 17-20, 2025; Orlando.
Reference:
Disclosures: Venkateswaran reports consulting for Zeiss.
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