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

Aim: To compare slit-lamp manual marking and Verion imageguidedmarking in toric intraocular lens (IOL) implantation usingvector analysis.Material and Method: Eyes with manual marking were defined asgroup 1 and eyes with Verion image-guided marking were definedas 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 and30 in group 2. Higher degrees of IOL rotation (≥10°) were predominantlyobserved in the manual marking group. Group 2 had a lowertoric IOL rotation in eyes with against-the-rule astigmatism than ingroup 1 (P=0.003). In Group 2, error size was negatively correlatedwith refractive astigmatism (r=−0.37, P=0.04), whereas the angleof error was positively correlated with best-corrected visual acuity(r=0.526, P=0.003).Conclusion: Vectorial analysis shows that digital marking is moreeffective and yields more predictable outcomes for toric IOL rotationcompared to manual marking, particularly in eyes withagainst-the-rule astigmatism and high astigmatism. This improvedpredictability is attributed to more accurate axis alignment.