This cross-sectional comparative study evaluated patients from a single cataract center. In each eye, manual horizontal meridian axis line was marked on the cornea using the manual peripheral corneal marking technique (Horizontal Slit Beam Marking ), while the Verion digital image-guided navigation system provided a reference axis fixed at the horizontal meridian (0°/180°). The primary outcome measure was the difference in degrees between the digital marker and the manual marker horizontal meridian as measured intraoperatively. Agreement was assessed using Bland-Altman analysis, reporting the mean bias (systematic error) and 95% limits of agreement (LoA, mean ± 1.96 SD). A misalignment of ±10° was defined as the threshold of clinical significance.