Comparison of 120- and 140-μm SMILE Cap Thickness Results in Eyes With Thick Corneas. Issue 10 (October 2016)

• Record Type: Journal Article
• Authors: Liu, Manli; Zhou, Yugui; Wu, Xianghua; Ye, Tiantian; Liu, Quan
• Is Part Of: Cornea. Volume 35:Issue 10(2016)
• Publication Date: 2016-10
• Subjects: small incision lenticule extraction -- cap thickness -- in vivo confocal microscopy -- 3-dimensional optical coherence tomography -- scanning electron microscope; Cornea -- Periodicals; Cornea -- Periodicals; Cornée -- Périodiques; 617.719
• DOI: 10.1097/ICO.0000000000000924
• Languages: English
• ISSNs: 0277-3740

Abstract

Abstract : Purpose: To evaluate clinical outcomes after small incision lenticule extraction (SMILE) with different cap thicknesses in thick corneas. Methods: Forty patients with central corneal thickness of more than 560 μm were recruited in this prospective, randomized, masked, paired-eye study. Patients were randomized to receive SMILE with a 120-μm cap thickness in 1 eye and 140-μm cap thickness in the other. Uncorrected and corrected distance visual acuity (CDVA), contrast sensitivity (CS), higher-order aberrations (HOAs), and morphologic modifications of corneal architecture were measured during the 3-month follow-up period. Results: Postoperative refractive outcomes, visual outcomes, CS, and the changes in HOAs were similar between both groups. The persistence of brightly reflective particles in the corneal interface layer was 1388.6 ± 219.5/mm 2 in eyes with 120-μm cap thickness and 54.7 ± 8.6/mm 2 in eyes with 140-μm cap thickness ( P < 0.001). The hyperreflectivity line at the interface layer almost disappeared in all eyes with 140-μm cap thickness, and it still persisted in 43% of the fellow eyes at 3 months postoperatively. The anterior surfaces of lenticules in the 140-μm cap thickness group exhibited more smoothness than in the 120-μm cap thickness group. Conclusions: There was a lower level corneal wound-healing response after SMILE with a 140-μm cap thickness than with a 120-μm cap thickness, although the thickness of cap creation did not affect visual outcomes by 3 months postoperatively.