Evaluation of 2 Cap Thickness Outcomes 1 Year After Refractive Lenticule Extraction Smile Compared to Femto-LASIK
Small incision lenticule extraction (SMILE, VisuMax, Carl Zeiss Meditec) treatment represents an alternative technique to treat myopic and astigmatic patients. Former studies showed comparable visual recovery as well as visual and aberrometric results compared to the Femto-LASIK technique. This study addresses the question, whether a residual cap of 140μm produces visual outcomes as predictable, safe and effective as 130μm caps compared to 100μm flaps.
The current investigation presents comparative results of 50 eyes in each SMILE group compared to 50 eyes in the Femto LASIK group. Follow up was performed between 1 day and up to 12 month after treatment. Results were evaluated by wave front analysis and subjective refraction. Patients were questioned for dry eye symptoms, comfort and recovery.
Concerning safety and efficiency of each method we could not detect significant differences. All three laser treatments, both SMILE groups and the Femto-LASIK group represented state-of-the-art status of both parameters. All groups showed a remarkable mean UDVA of < 0.05 logMAR one year after treatment. Visual recovery in the SMILE groups was as fast as with the Flap-based LASIK. Less dry eyes as well as better patient comfort and less pain sensation were observed in the SMILE groups.
Visual recovery, safety, effectiveness and predictability shows similar results in all 3 groups, while deficits in comfort were greater in the Femto LASIK group. No dry eye sensations were observed in the SMILE group. The tissue removal in deeper corneal layers and a small incision of only 2-3mm may result in more stable corneas after SMILE surgery. Therefore we clearly favor the SMILE technique in any aspects compared to the traditional FLAP-based LASIK.