Visual, Refractive, Dry Eye And Corneal Clarity Outcomes Of Small Incision Lenticule Extraction (Smile)

To report the visual, refractive and densitometric outcomes of small incision lenticule extraction (SMILE).

Envision Eye Centre, Sydney

Prospective study on 49 eyes of 25 patients that underwent SMILE for mild to moderate myopia (< 6 dioptres) and myopic astigmatism. Main outcome measures at 1 month included uncorrected visual acuity (UCVA) in logMAR, spherical equivalent (SE) in dioptres (D), wavefront higher order aberrations (HOA) and tear film osmolality (TFO). Corneal densitometry (CD) at 0-2mm, 2-6-mm zones at anterior 120 μm, mid-cornea and total corneal values were measured. 

 

Post SMILE, 95.91% of treated eyes had a postoperative logMAR UCVA of 0.0 or better. Mean preoperative SE was -3.61D ± 1.11D with mean postoperative refractive error of -0.07± 0.29D (p <0.0001). The mean preoperative refractive cylinder of 0.50 ± 0.58 D was reduced to 0.15 ± 0.25D (p <0.0001). Postoperative SE within ± 0.50 D and within 1.00 D was noted in 93.9% and 100% eyes respectively. 

 There was no statistically significant difference in TFO from preoperatively 299.42 ±12.18 to 295.05 ± 10.20 mOsm/l postoperatively (p=0.08). A significant increase in HOA was noted from 0.33 ± 0.09 to 0.68 ± 0.90 (p = 0.009). No significant changes in CD were noted except for a significant increase in the total mid-corneal layer (p <0.0001).

Early postoperative results indicate that SMILE is effective in correcting mild to moderate myopia and myopic astigmatism with good visual outcomes and favourable dry eye profile.