Abstract
Objectives
To compare outcomes of femtosecond-enabled deep anterior lamellar keratoplasty (FE-DALK) and standard deep anterior lamellar keratoplasty (S-DALK).
Methods
An open label, randomized controlled trial (Kensington Eye Institute, Toronto, ON, Canada) including 100 eyes of 97 participants with either keratoconus or corneal scarring, randomized to either FE-DALK (n = 48) or S-DALK (n = 49). Primary outcomes: postoperative astigmatism and surgically induced corneal astigmatism (SIA) – both at 15 months. Secondary outcomes: 6-, 12- and 15-month postoperative uncorrected- and best spectacle-corrected visual acuity, steep and flat keratometry, manifest sphere and astigmatism, rate of conversion to penetrating keratoplasty (PK), big-bubble success, central corneal thickness, endothelial cell count and complications.
Results
In intention-to-treat analysis, mean postoperative astigmatism in the FE-DALK (n = 30) and S-DALK (n = 30) groups at 15 months was 7.8 ± 4.4 D and 6.3 ± 5.0 D, respectively (p = 0.282) with an adjusted mean difference of 1.3 D (95% CI −1.08, +3.65). Mean SIA (arithmetic) was 9.2 ± 7.8 and 8.8 ± 5.4 D, respectively (p = 0.838) with a mean difference of 0.4 D (95% CI −3.13, +3.85). In an analysis of successful DALK cases only, mean postoperative astigmatism in the FE-DALK (n = 24) and S-DALK (n = 20) groups at 15 months (after excluding 4 eyes with AEs) was 7.3 ± 4.4 and 6.2 ± 4.9 D, respectively (p = 0.531) with an adjusted mean difference of 0.9 D (95% CI −1.94, +3.71). Mean SIA (arithmetic) was 9.1 ± 7.8 and 7.9 ± 4.6 D, respectively (p = 0.547) with a mean difference of 1.2 D (95% CI −2.70,+5.02). Comparison of secondary outcomes showed only weak statistical evidence.
Conclusions
In this randomized controlled trial, FE-DALK and S-DALK showed comparable functional and anatomical outcomes.
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Data availability
The datasets generated and analyzed during the current study are not publicly available to protect individual privacy but are available from the corresponding author on reasonable request following the approval of the University of Toronto Research Ethics Board.
References
Shimmura S, Tsubota K. Deep anterior lamellar keratoplasty. Curr Opin Ophthalmol. 2006;17:349–55.
Tan DTH, Mehta JS. Future directions in lamellar corneal transplantation. Cornea. 2007;26:S21–8.
Reinhart WJ, Musch DC, Jacobs DS, Lee WB, Kaufman SC, Shtein RM. Deep anterior lamellar keratoplasty as an alternative to penetrating keratoplasty a report by the american academy of ophthalmology. Ophthalmology. 2011;118:209–18.
Archila EA. Deep lamellar keratoplasty dissection of host tissue with intrastromal air injection. Cornea. 1984;3:217–8.
Gaster RN, Dumitrascu O, Rabinowitz YS. Penetrating keratoplasty using femtosecond laser-enabled keratoplasty with zig-zag incisions versus a mechanical trephine in patients with keratoconus. Br J Ophthalmol. 2012;96:1195–9.
Kamiya K, Kobashi H, Shimizu K, Igarashi A. Clinical outcomes of penetrating keratoplasty performed with the VisuMax femtosecond laser system and comparison with conventional penetrating keratoplasty. PLoS ONE. 2014;9:1–6.
Alio JL, Abdelghany AA, Barraquer R, Hammouda LM, Sabry AM. Femtosecond laser assisted deep anterior lamellar keratoplasty outcomes and healing patterns compared to manual technique. Biomed Res Int. 2015;2015:397891.
Li S, Wang T, Bian J, Wang F, Han S, Shi W. Precisely controlled side cut in femtosecond laser-assisted deep lamellar keratoplasty for advanced keratoconus. Cornea. 2016;35:1289–94.
Shehadeh-Mashor R, Chan CC, Bahar I, Lichtinger A, Yeung SN, Rootman DS. Comparison between femtosecond laser mushroom configuration and manual trephine straight-edge configuration deep anterior lamellar keratoplasty. Br J Ophthalmol. 2014;98:35–39.
Chan CC, Ritenour RJ, Kumar NL, Sansanayudh W, Rootman DS. Femtosecond laser-assisted mushroom configuration deep anterior lamellar keratoplasty. Cornea. 2010;29:290–5.
Anwar M, Teichmann KD. Big-bubble technique to bare Descemet’s membrane in anterior lamellar keratoplasty. J Cataract Refract Surg. 2002;28:398–403.
Melles GR, Lander F, Rietveld FJ, Remeijer L, Beekhuis WH, Binder PS. A new surgical technique for deep stromal, anterior lamellar keratoplasty. Br J Ophthalmol. 1999;83:327–33.
Shehadeh-Mashor R, Chan C, Yeung SN, Lichtinger A, Amiran M, Rootman DS. Long-term outcomes of femtosecond laser-assisted mushroom configuration deep anterior lamellar keratoplasty. Cornea. 2013;32:390–5.
Alpins NA, Goggin M. Practical astigmatism analysis for refractive outcomes in cataract and refractive surgery. Surv Ophthalmol. 2004;49:109–22.
Moher D, Schulz KF, Altman DG, Lepage L. The CONSORT statement: revised recommendations for improving the quality of reports of parallel-group randomized trials. Ann Intern Med. 2001;134:657–62.
Liu YC, Wittwer VV, Yusoff NZM, Lwin CN, Seah XY, Mehta JS, et al. Intraoperative optical coherence tomography-guided femtosecond laser-assisted deep anterior lamellar keratoplasty. Cornea. 2019;38:648–53.
Guindolet D, Nguyen DT, Bergin C, Doan S, Cochereau I, Gabison EE. Double-docking technique for femtosecond laser-assisted deep anterior lamellar keratoplasty. Cornea. 2018;37:123–6.
Gogri PY, Bore MC, Rips AGT, Reddy JC, Rostov AT, Vaddavalli PK. Femtosecond laser-assisted big bubble for deep anterior lamellar keratoplasty. J Cataract Refract Surg. 2021;47:106–10.
Lucisano A, Giannaccare G, Pellegrini M, Bernabei F, Yu AC, Carnevali A, et al. Preliminary results of a novel standardized technique of femtosecond laser-assisted deep anterior lamellar keratoplasty for keratoconus. J Ophthalmol. 2020;2020:5496162.
Yoo SH, Hurmeric V. Femtosecond laser-assisted keratoplasty. Am J Ophthalmol. 2011;151:189–91.
Deshmukh R, Stevenson LJ, Vajpayee RB. Laser-assisted corneal transplantation surgery. Surv Ophthalmol. 2021;66:826–37.
Acknowledgements
We would like to acknowledge Professor Noel Alpins for his assistance and guidance in the planning of vector analysis in the study, and Ms. Fei Zuo for her assistance in data analysis.
Funding
This study is funded by Kensington Research Institute.
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NSo was responsible for designing the study, drafting the protocol, analysis planning, interpreting results, and drafting the manuscript. WH was responsible for designing the study, drafting the protocol, recruiting participants, collecting data, interpreting results, and revising the manuscript. MM was responsible for analysis planning, interpreting results and revising the manuscript. HFC was responsible for recruiting participants, collecting data, and revising the manuscript. DSR was responsible for recruiting participants, collecting data, and revising the manuscript. ARS was responsible for recruiting participants, collecting data, and revising the manuscript. MCB was responsible for recruiting participants, collecting data, and revising the manuscript. CCC was responsible for recruiting participants, collecting data, and revising the manuscript. KET was responsible for analysis planning, performing the analysis, interpreting results, and revising the manuscript. MP was responsible for designing the study, drafting the protocol, and revising the manuscript. VS was responsible for recruiting participants, conducting follow-up testing, collecting data, and revising the manuscript. NSi was responsible for designing the study, analysis planning, drafting the protocol, supervising study procedures, recruiting participants, collecting data, interpreting results, and revising the manuscript.
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Sorkin, N., Hatch, W., Mimouni, M. et al. A randomized controlled trial comparing femtosecond-enabled deep anterior lamellar keratoplasty and standard deep anterior lamellar keratoplasty (FEDS Study). Eye 37, 2693–2699 (2023). https://doi.org/10.1038/s41433-023-02387-1
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DOI: https://doi.org/10.1038/s41433-023-02387-1