Objective: To analyze the factors that affect the dynamic cyclotorsion component (DCC) during femtosecond laser in situ keratomileusis (FS-LASIK). Methods: In this retrospective study, we analyzed 500 patients (1 000 eyes) who underwent bilateral FS-LASIK for correction of myopic astigmatism from June 2015 to July 2016 at Eye Hospital, Wenzhou Medical University. Ablation was performed using the SCHWIND AMARIS (750S) excimer laser system, and the magnitude of dynamic cyclotorsion was recorded during the operation. Differences of DCC between left and right eyes were compared with paired t-tests. The factors that affect DCC were analyzed using multivariate linear regression. The main factors were age, eye (right or left), gender, spherical equivalent (SE), pre-ablation spherical and astigmatism,ablation zone, ablation time, central ablation depth, and temperature and humidity in the laser cavity. The cut-off points were measured using receiver operating characteristic curves. Results: The mean DCC amplitude was 1.61°±0.90°, with 1.50°±0.85° in right eyes and 1.71°±0.94° in left eyes (t=-4.85, P<0.001).
The mean dynamic cyclortorsion degree (absolute value) was 1.44°±0.93°, with 1.32°±0.91° in right eyes and 1.56±0.95° in left eyes (t=-4.87, P<0.001). Ablation time (β=0.022, P<0.001), age (β=-0.026,P<0.001), eye (right or left, β=-0.213, P<0.001), and humidity in the laser cavity (β=-0.018, P=0.008) were statistically significant factors for the DCC amplitude. Eye (right or left, β=-0.238, P<0.001), age (β=-0.019, P=0.001), and humidity in the laser cavity (β=-0.016, P=0.025) were significant factors for the absolute degree of DCC. Conclusions: Ablation time, age, eye (right or left), and humidity in the laser cavity can affect the DCC during binocular FS-LASIK.
Neuhann IM, Lege BA, Bauer M, et al. Static and dynamic rotational eye tracking during LASIK treatment of myopic astigmatism with the Zyoptix laser platform and Advanced
Control Eye Tracker. J Refract Surg, 2010, 26(1): 17-27. DOI:10.3928/1081597X-20101215-03.
[2]
Chang J. Cyclotorsion during laser in situ keratomileusis. JCataract Refract Surg, 2008, 34(10): 1720-1726. DOI: 10.1016/j.jcrs.2008.06.027.
[1]
Neuhann IM, Lege BA, Bauer M, et al. Static and dynamic rotational eye tracking during LASIK treatment of myopic astigmatism with the Zyoptix laser platform and Advanced
Control Eye Tracker. J Refract Surg, 2010, 26(1): 17-27. DOI:10.3928/1081597X-20101215-03.
[2]
Chang J. Cyclotorsion during laser in situ keratomileusis. JCataract Refract Surg, 2008, 34(10): 1720-1726. DOI: 10.1016/j.jcrs.2008.06.027.
[3]
Tjon-Fo-Sang MJ, de Faber JT, Kingma C, et al. Cyclotorsion: a possible cause of residual astigmatism in refractive surgery. J Cataract Refract Surg, 2002, 28(4): 599-602.
Arba-Mosquera S, Arbelaez MC. Three-month clinical outcomes with static and dynamic cyclotorsion correction using the SCHWIND AMARIS. Cornea, 2011, 30(9): 951-957. DOI:
[3]
Tjon-Fo-Sang MJ, de Faber JT, Kingma C, et al. Cyclotorsion: a possible cause of residual astigmatism in refractive surgery. J Cataract Refract Surg, 2002, 28(4): 599-602.
Alio JL, Pachkoria K, El AA, et al. Laser-assisted in situ keratomileusis in high mixed astigmatism with optimized,fast-repetition and cyclotorsion control excimer laser. Am J
Alio JL, Pachkoria K, El AA, et al. Laser-assisted in situ keratomileusis in high mixed astigmatism with optimized,fast-repetition and cyclotorsion control excimer laser. Am J
Swami AU, Steinert RF, Osborne WE, et al. Rotational malposition during laser in situ keratomileusis. Am J Ophthalmol, 2002, 133(4): 561-562.
[9]
Swami AU, Steinert RF, Osborne WE, et al. Rotational malposition during laser in situ keratomileusis. Am J Ophthalmol, 2002, 133(4): 561-562.
[10]
Ciccio AE, Durrie DS, Stahl JE, et al. Ocular cyclotorsion during customized laser ablation. J Refract Surg, 2005, 21(6):S772-774.
[10]
Ciccio AE, Durrie DS, Stahl JE, et al. Ocular cyclotorsion during customized laser ablation. J Refract Surg, 2005, 21(6):S772-774.
[11]
Hori-Komai Y, Sakai C, Toda I, et al. Detection of cyclotorsional rotation during excimer laser ablation in LASIK. J Refract Surg,2007, 23(9): 911-915.
[11]
Hori-Komai Y, Sakai C, Toda I, et al. Detection of cyclotorsional rotation during excimer laser ablation in LASIK. J Refract Surg,2007, 23(9): 911-915.
[12]
Prakash G, Ashok KD, Agarwal A, et al. Predictive factor analysis for successful performance of iris recognitionassisted dynamic rotational eye tracking during laser in situ
keratomileusis. Am J Ophthalmol, 2010, 149(2): 229-237.e2.DOI: 10.1016/j.ajo.2009.08.021.
[13]
Tomita M, Watabe M, Yukawa S, et al. Supplementary effect of static cyclotorsion compensation with dynamic cyclotorsion compensation on the refractive and visual outcomes of laser in situ keratomileusis for myopic astigmatism. J Cataract Refract Surg, 2013, 39(5): 752-758. DOI: 10.1016/j.jcrs.2012.11.030.
[14]
Arba MS, Arbelaez MC. Use of a six-dimensional eye-tracker in corneal laser refractive surgery with the SCHWIND AMARIS Total Tech laser. J Refract Surg, 2011, 27(8): 582-590. DOI:10.3928/1081597X-20110120-02.
[15]
Febbraro JL, Koch DD, Khan HN, et al. Detection of static cyclotorsion and compensation for dynamic cyclotorsion in laser in situ keratomileusis. J Cataract Refract Surg, 2010, 36(10):1718-1723. DOI: 10.1016/j.jcrs.2010.05.019.
Prakash G, Ashok KD, Agarwal A, et al. Predictive factor analysis for successful performance of iris recognitionassisted dynamic rotational eye tracking during laser in situ
keratomileusis. Am J Ophthalmol, 2010, 149(2): 229-237.e2.DOI: 10.1016/j.ajo.2009.08.021.
[13]
Tomita M, Watabe M, Yukawa S, et al. Supplementary effect of static cyclotorsion compensation with dynamic cyclotorsion compensation on the refractive and visual outcomes of laser in situ keratomileusis for myopic astigmatism. J Cataract Refract Surg, 2013, 39(5): 752-758. DOI: 10.1016/j.jcrs.2012.11.030.
[14]
Arba MS, Arbelaez MC. Use of a six-dimensional eye-tracker in corneal laser refractive surgery with the SCHWIND AMARIS Total Tech laser. J Refract Surg, 2011, 27(8): 582-590. DOI:10.3928/1081597X-20110120-02.
[15]
Febbraro JL, Koch DD, Khan HN, et al. Detection of static cyclotorsion and compensation for dynamic cyclotorsion in laser in situ keratomileusis. J Cataract Refract Surg, 2010, 36(10):1718-1723. DOI: 10.1016/j.jcrs.2010.05.019.