Elsevier

Ophthalmology

Volume 122, Issue 4, April 2015, Pages 669-676
Ophthalmology

Original article
Dry Eye Disease after Refractive Surgery: Comparative Outcomes of Small Incision Lenticule Extraction versus LASIK

https://doi.org/10.1016/j.ophtha.2014.10.004Get rights and content

Purpose

To compare small incision lenticule extraction (SMILE) versus LASIK for post-refractive dry eye disease.

Design

Prospective, comparative, nonrandomized clinical study.

Participants

Thirty patients scheduled for bilateral myopic SMILE and 30 age-, sex-, and refraction-matched patients scheduled for bilateral myopic LASIK were enrolled and followed for 6 months after the surgery.

Methods

Complete evaluation of dry eye disease was performed at 1 and 6 months postoperatively, which included vision-related quality of life (Ocular Surface Disease Index [OSDI]), clinical examinations (tear film breakup time [TBUT], Schirmer I test, corneal staining), and tear osmolarity measurements, together with an overall severity score. Function and morphology of the corneal innervation were evaluated by corneal esthesiometry and subbasal nerve imaging using in vivo confocal microscopy (IVCM).

Main Outcome Measures

Overall analysis of dry eye disease and corneal innervation.

Results

High incidence of mild to moderate dry eye disease was observed in both groups 1 month postoperatively, which remained significantly higher in the LASIK group than in the SMILE group 6 months after surgery (overall severity score [0–4]: 1.2±1.1 vs. 0.2±0.4, respectively, P < 0.01), leading to more frequent use of tear substitutes over the long term. Corneal sensitivity was better in SMILE than in LASIK eyes 1 month postoperatively (3.5±1.79 vs. 2.45±2.48, respectively, P < 0.01) and then recovered to statistically similar values at 6 months. Corneal nerve density, number of long fibers, and branchings as assessed by IVCM were significantly higher in the SMILE group compared with the LASIK group 1 and 6 months after surgery. Corneal sensitivity was negatively correlated with dry eye-related corneal damage (R² = 0.48, P < 0.01), and the long fiber nerve density was independently correlated with the OSDI score (R² = 0.50, P < 0.01) and the Schirmer test (R² = 0.21, P < 0.01) 6 months postoperatively.

Conclusions

The SMILE procedure has a less pronounced impact on the ocular surface and corneal innervation compared with LASIK, further reducing the incidence of dry eye disease and subsequent degradation in quality of life after refractive surgery.

Section snippets

Methods

This prospective, comparative, nonrandomized clinical study was conducted in the Clinical Center for Investigation of Ocular Surface Pathology (Quinze-Vingts National Ophthalmology Hospital, National Institute for Health and Medical Research 503, Paris, France) in accordance with the Declaration of Helsinki, Scotland amendment, 2000. Previous approval was obtained from the National Ethical Research Committee (Comité de Protection des Personnes Ile de France V, National Agreement Number 10793).

Results

No adverse effects occurred in any of the 120 procedures. Six-month postoperative best-uncorrected visual acuity and residual spherical equivalent were not statistically different between SMILE and LASIK eyes, as detailed in Table 1. Morphologic parameters including the keratometry, epithelial thickness, and total thickness of the cornea, and the mean depth of the interface, as assessed by OCT, did not differ between the 2 groups.

Discussion

Dry eye is still the most frequent complication of refractive surgery.14 Post-refractive dry eye disease is an immediate issue because the patients' visual comfort and quality of life dictate their overall satisfaction.15 On a more global scale, ocular dryness after refractive surgery may lead to permanent pain, visual fluctuations, and the need for daily treatment, which affects health status, quality of life, and vision when it lasts for months or even years. New corneal procedures, such as

References (41)

  • A.J. Kanellopoulos et al.

    Comparison of corneal sensation following photorefractive keratectomy and laser in situ keratomileusis

    J Cataract Refract Surg

    (1997)
  • T.U. Linna et al.

    Recovery of corneal nerve morphology following laser in situ keratomileusis

    Exp Eye Res

    (1998)
  • Y. Murakami et al.

    Prospective, randomized comparison of self-reported postoperative dry eye and visual fluctuation in LASIK and photorefractive keratectomy

    Ophthalmology

    (2012)
  • A. Leonardi et al.

    Cytokine and chemokine levels in tears and in corneal fibroblast cultures before and after excimer laser treatment

    J Cataract Refract Surg

    (2009)
  • J.C. Erie et al.

    Long-term keratocyte deficits in the corneal stroma after LASIK

    Ophthalmology

    (2004)
  • Eye health statistics at a glance. Compiled by American Academy of Ophthalmology. Available at:...
  • The definition and classification of dry eye disease: report of the definition and classification subcommittee of the International Dry Eye Workshop

    Ocul Surf

    (2007)
  • N. Deschamps et al.

    The impact of dry eye disease on visual performance while driving

    Am J Ophthalmol

    (2013)
  • M.P. Calvillo et al.

    Corneal reinnervation after LASIK: prospective 3-year longitudinal study

    Invest Ophthalmol Vis Sci

    (2004)
  • Y. Feng et al.

    The effect of hinge location on corneal sensation and dry eye after LASIK: a systematic review and meta-analysis

    Graefes Arch Clin Exp Ophthalmol

    (2013)
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    Financial Disclosure(s): The author(s) have made the following disclosure(s):

    A.D.: Consultant – Alcon, Thea, Abbott Medical Optics, Bausch & Lomb; Grants/grants pending – INSERM and UPMC University Paris 6; Inventor – 2 patents belonging to INSERM. C.B.: Board member and consultant – Alcon, Allergan, MSD, Thea, Santen; grants/grants pending – Allergan, MSD, Thea, Santen; Co-inventor – 2 patents belong to INSERM.

    Public grant from the French National Institute of Health and Medical Research. The funding organization had no role in the design or conduct of this research.

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