Comparing Manual and Verion Image-guided Marking Methods in Toric Intraocular Lens Implantation: A Vector Analysis Study

Year 2026, Volume: 16 Issue: 1, 54 - 61, 19.03.2026

Ezgi Karataş , Aylin Yaman , Arif Taylan Öztürk , Mahmut Kaya Ziya Ayhan

https://izlik.org/JA65ZE48SN

Abstract

Aim: To compare slit-lamp manual marking and Verion imageguided
marking in toric intraocular lens (IOL) implantation using
vector analysis.
Material and Method: Eyes with manual marking were defined as
group 1 and eyes with Verion image-guided marking were defined
as group 2. Target-induced and surgically induced astigmatism,
the magnitude and angle of error, the success index, toric IOL rotation,
and refractive outcomes were compared.
Results: A total of 67 eyes were examined, with 37 in group 1 and
30 in group 2. Higher degrees of IOL rotation (≥10°) were predominantly
observed in the manual marking group. Group 2 had a lower
toric IOL rotation in eyes with against-the-rule astigmatism than in
group 1 (P=0.003). In Group 2, error size was negatively correlated
with refractive astigmatism (r=−0.37, P=0.04), whereas the angle
of error was positively correlated with best-corrected visual acuity
(r=0.526, P=0.003).
Conclusion: Vectorial analysis shows that digital marking is more
effective and yields more predictable outcomes for toric IOL rotation
compared to manual marking, particularly in eyes with
against-the-rule astigmatism and high astigmatism. This improved
predictability is attributed to more accurate axis alignment.

Keywords

astigmatism , phacoemulsification , image-guided marking , manual marking , toric intraocular lens , vector analysis

References

• 1. Moshirfar M, Martin DJ, Jensen JL, Payne CJ. Light-adjustable intraocular lenses: an updated platform for cataract surgery. Curr Opin Ophthalmol. 2023;34(1):78–83. https://doi. org/10.1097/ICU.0000000000000911
• 2. Lapp T, Wacker K, Heinz C, Maier P, Eberwein P, Reinhard T. Cataract surgery-indications, techniques, and intraocular lens selection. Dtsch Arztebl Int. 2023;120(21):377–386. https:// doi.org/10.3238/arztebl.m2023.0028
• 3. Varsits RM, Hirnschall N, Döller B, Findl O. Evaluation of an intraoperative toric intraocular lens alignment system using an image-guided system. J Cataract Refract Surg. 2019;45(9):1234– 1238. https://doi.org/10.1016/j.jcrs.2019.04.009
• 4. Savini G, Versaci F, Vestri G, Ducoli P, Næser K. Influence of posterior corneal astigmatism on total corneal astigmatism in eyes with moderate to high astigmatism. J Cataract Refract Surg. 2014;40(10):1645–1653. https://doi.org/10.1016/j.jcrs.2014.01.046
• 5. Alcon Online Toric IOL Calculator. Accessed May 18, 2024.
• 6. Kawahara A, Takayanagi Y. Vector analysis investigation of toric intraocular lens with no deviation from the intended axis. Clin Ophthalmol. 2016;10:2199. https://doi.org/10.2147/OPTH. S119755
• 7. Alpins NA. A new method of analyzing vectors for changes in astigmatism. J Cataract Refract Surg. 1993;19(4):524–533. https://doi.org/10.1016/S0886-3350(13)80617-7
• 8. Eğrilmez S, Dalkılıç G, Yağcı A. Vector analysis software on analyzing astigmatism. Turk Gazi Ophthalmol. 2003;33(3/1):404–416.
• 9. Villegas EA, Alcón E, Artal P. Minimum amount of astigmatism that should be corrected. J Cataract Refract Surg. 2014;40(1):13–19. https://doi.org/10.1016/j.jcrs.2013.09.010
• 10. Rocha-de-Lossada C, Rodríguez-Vallejo M, Rodríguez-Calvode-Mora M, Ribeiro FJ, Fernández J. Managing low corneal astigmatism in patients with presbyopia correcting intraocular lenses: a narrative review. BMC Ophthalmology. 2023;23(1):1–12. https://doi.org/10.1186/s12886-023-03003-2
• 11. Schultz T, Hoffmann S, Dick HB. Comparison of toric intraocular lens alignment between femtosecond laser-assisted capsular marking and digital marking. J Cataract Refract Surg. 2024;50(3):230–235. https://doi.org/10.1097/j.jcrs.0000000000001344
• 12. Yao L, Jia S, Yang X, Li M, Yu X, Zhao P, et al. Image-guided marking versus manual marking in phacoemulsification with toric intraocular lens (IOL) implantation: a systematic review and meta-analysis of randomized clinical trials. Semin Ophthalmol. 2024;39(1):60–65. https://doi.org/10.1080/0820538.2023.2231575
• 13. Visser N, Berendschot TTJM, Bauer NJC, Jurich J, Kersting O, Nuijts RMMA. Accuracy of toric intraocular lens implantation in cataract and refractive surgery. J Cataract Refract Surg. 2011;37(8):1394–1402. https://doi.org/10.1016/j.jcrs.2011.02.024
• 14. Zhou F, Jiang W, Lin Z, Li X, Li J, Lin H, et al. Comparative meta-analysis of toric intraocular lens alignment accuracy in cataract patients: image-guided system versus manual marking. J Cataract Refract Surg. 2019;45(9):1340–1345. https://doi.org/10.1016/j.jcrs.2019.03.030
• 15. Mohankumar A, Mohan S. Toric intraocular lenses. 2023. In: StatPearls [Internet]. Treasure Island (FL): StatPearlsPublishing; 2026 Jan–.