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Published in: Lasers in Medical Science 3/2020

01-04-2020 | Incision | Original Article

Changes in corneal biomechanics during small-incision lenticule extraction (SMILE) and femtosecond-assisted laser in situ keratomileusis (FS-LASIK)

Authors: Kaiwei Cao, Lina Liu, Ting Yu, Feng Chen, Ji Bai, Ting Liu

Published in: Lasers in Medical Science | Issue 3/2020

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Abstract

Observe the influence of femtosecond laser cutting on corneal biomechanics during small-incision lenticule extraction (SMILE) or femtosecond-assisted laser in situ keratomileusis (FS-LASIK) and assess the biomechanical changes following the operation. Prospective, non-randomized study. A total of 80 eyes from 80 patients were treated with either SMILE or FS-LASIK. Parameters of inverse concave radius, deformation amplitude ratio 2 mm or 1 mm (DA ratio 2 mm or 1 mm), highest concavity radius (HC radius), biomechanically corrected intraocular pressure (bIOP), and central corneal thickness (CCT) measured by Corvis ST II were recorded at 1 day preoperatively, immediately after the lenticule or flap creation, during subsequent lenticule extraction or excimer laser ablation, and during follow-up at 1 week, 1 month and 3 months postoperatively. After lenticule creation, the DA ratio 2 mm or 1 mm was bigger (p < 0.05), meanwhile, CCT was thicker (p < 0.05) than with flap creation. Partial parameters changed significantly after lenticule creation or flap creation, and all parameters changed significantly after tissue removal. All parameters showed no significant differences between the two groups (p > 0.05) after operation. The variations in bIOP (ΔbIOP) after operation were significantly less than those in Δnon-contact IOP (p < 0.001) in two groups. Femtosecond laser cutting during lenticule creation has a greater impact on corneal biomechanics than flap creation. Both the femtosecond laser cutting and removal of tissue degrade corneal biomechanics; however, these effects may be predominantly a result of tissue removal. SMILE and FS-LASIK have no differences in corneal biomechanics when the same CCT is consumed. bIOP is more reliable after the operation, but further study is essential.
Literature
1.
go back to reference Anderle R, Ventruba J (2013) The current state of refractive surgery. Coll Antropol 37(Suppl 1):237–241PubMed Anderle R, Ventruba J (2013) The current state of refractive surgery. Coll Antropol 37(Suppl 1):237–241PubMed
2.
go back to reference Tataru CP (2017) The current state of refractive surgery. Rom J Ophthalmol 61(4):237–238CrossRef Tataru CP (2017) The current state of refractive surgery. Rom J Ophthalmol 61(4):237–238CrossRef
3.
go back to reference Wang JC, Hufnagel TJ, Buxton DF (2003) Bilateral keratectasia after unilateral laser in situ keratomileusis: a retrospective diagnosis of ectatic corneal disorder. J Cataract Refract Surg 29(10):2015–2018CrossRef Wang JC, Hufnagel TJ, Buxton DF (2003) Bilateral keratectasia after unilateral laser in situ keratomileusis: a retrospective diagnosis of ectatic corneal disorder. J Cataract Refract Surg 29(10):2015–2018CrossRef
5.
go back to reference Andreassen TT, Simonsen AH, Oxlund H (1980) Biomechanical properties of keratoconus and normal corneas. Exp Eye Res 31(4):435–441CrossRef Andreassen TT, Simonsen AH, Oxlund H (1980) Biomechanical properties of keratoconus and normal corneas. Exp Eye Res 31(4):435–441CrossRef
6.
go back to reference Schmack I, Dawson DG, McCarey BE, Waring GO 3rd, Grossniklaus HE, Edelhauser HF (2005) Cohesive tensile strength of human LASIK wounds with histologic, ultrastructural, and clinical correlations. J Refract Surg 21(5):433–445CrossRef Schmack I, Dawson DG, McCarey BE, Waring GO 3rd, Grossniklaus HE, Edelhauser HF (2005) Cohesive tensile strength of human LASIK wounds with histologic, ultrastructural, and clinical correlations. J Refract Surg 21(5):433–445CrossRef
11.
go back to reference Joda AA, Shervin MM, Kook D, Elsheikh A (2016) Development and validation of a correction equation for Corvis tonometry. Comput Methods Biomech Biomed Engin 19(9):943–953CrossRef Joda AA, Shervin MM, Kook D, Elsheikh A (2016) Development and validation of a correction equation for Corvis tonometry. Comput Methods Biomech Biomed Engin 19(9):943–953CrossRef
13.
go back to reference Lee H, Roberts CJ, Kim TI, Ambrosio R Jr, Elsheikh A, Yong Kang DS (2017) Changes in biomechanically corrected intraocular pressure and dynamic corneal response parameters before and after transepithelial photorefractive keratectomy and femtosecond laser-assisted laser in situ keratomileusis. J Cataract Refract Surg 43(12):1495–1503. https://doi.org/10.1016/j.jcrs.2017.08.019 CrossRefPubMed Lee H, Roberts CJ, Kim TI, Ambrosio R Jr, Elsheikh A, Yong Kang DS (2017) Changes in biomechanically corrected intraocular pressure and dynamic corneal response parameters before and after transepithelial photorefractive keratectomy and femtosecond laser-assisted laser in situ keratomileusis. J Cataract Refract Surg 43(12):1495–1503. https://​doi.​org/​10.​1016/​j.​jcrs.​2017.​08.​019 CrossRefPubMed
Metadata
Title
Changes in corneal biomechanics during small-incision lenticule extraction (SMILE) and femtosecond-assisted laser in situ keratomileusis (FS-LASIK)
Authors
Kaiwei Cao
Lina Liu
Ting Yu
Feng Chen
Ji Bai
Ting Liu
Publication date
01-04-2020
Publisher
Springer London
Published in
Lasers in Medical Science / Issue 3/2020
Print ISSN: 0268-8921
Electronic ISSN: 1435-604X
DOI
https://doi.org/10.1007/s10103-019-02854-w

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