Abstract:  Objective To evaluate the difference and consistency of papillary offset values of myopic patients measured by two anterior segment  analyzers: Scansys and Pentacam. Meanwhile, to discuss the correlation of increment of higher order abberations (HOAs) after SMILE and papillary offset values as well as the correlation of ablation induced decentration after SMILE and papillary offset values. Design Consistency evaluation study. Participants 185 eyes of 96 patients who received SMILE at General Hospital of Central Theater Command. Methods Parameters of papillary offset values were recorded preoperatively by Scansys and Pentacam. Ablation induced decentration and preoperative and postoperative HOAs were recorded by Pentacam. Wilcoxon signed rank test was used to compare the difference between Scansys and Pentacam, the intraclass correlation coefficient (ICC) and Bland-Altman analysis were used to evaluate the agreement between Scansys and Pentacam. Pearson correlation analysis was used to discuss the correlation analysis. Main Outcome Measures ICC of papillary offset values by Scansys and Pentacam, correlation index. Results The highest proportion of the deviation of the pupil center from corneal vertex measured by Scansys and Pentacam was in the superotemporal and supernasal. The ICC for horizontal offset value, vertical offset value, total offset value and offset axis of the right eyes were 0.74, 0.78, 0.73 and 0.59; 0.77, 0.78, 0.84 and 0.66 for the left eyes; 0.75, 0.78, 0.79 and 0.63 for both eyes. The mean difference in horizontal offset value, vertical offset value, total offset value and offset axis for the right eyes were（-0.04±0.08）mm, （0.02±0.07）mm, （0.02±0.07）mm, （8.2±66）° (all P＜0.05); （0.01±0.09）mm (P=0.527), （0.02±0.07）mm (P＜0.05), （0.00±0.06）mm (P=0.650), （-20±72）° (P=0.527) for the left eyes; （-0.01±0.09）mm (P＜0.05),（0.02±0.07）mm (P＜0.05), （0.01±0.06）mm (P＜0.05), （-5.8±70）° (P=0.409) for both eyes. The total HOA, spherical aberration, vertical coma, trefoil 0 increased significantly after SMILE (all P＜0.05). There was no correlation between papillary offset values and HOAs increments or ablation induced decentration. Conclusion Results of papillary offset values of Scansys were slightly larger than the results of Pentacam, but the differences have no effect on the HOAs increments or ablation induced decentration. So, the results of two devices can be referred to each other. (Ophthalmol CHN, 2024, 33: 205-211)

Key words: Scansys, Pentacam, pupillary offset values