Abstract
PURPOSE: This study aimed to evaluate the safety and effectiveness of Ray-Tracing Guided LASIK surgery and to compare the refractive outcomes and visual quality between patients with spherical equivalent (SEQ) differences of ≤ 0.75D and > 0.75D, as measured by the InnovEyes sightmap and subjective refraction. DESIGN: Prospective, observational cohort study. SUBJECTS: Forty-six patients (89 eyes) undergoing Ray-Tracing Guided LASIK with preoperative SEQ differences between sightmap and subjective refraction of either ≤ 0.75D or > 0.75D. METHODS: Patients underwent preoperative examinations using InnovEyes sightmap diagnostic equipment to detect and measure biological parameters. A ray tracing-based algorithm was used to determine ablation contours, with direct application of ablation data for SEQ differences ≤ 0.75D and parameter adjustment for differences > 0.75D. Outcomes included uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), manifest refraction spherical equivalent (MRSE), and total higher-order aberration (HOAs), measured preoperatively and six months postoperatively. RESULTS: Six months post-surgery, 100% of eyes in both groups achieved a postoperative UDVA of at least 20/25, with 76% of the ≤ 0.75D group and 81% of > 0.75D reaching 20/16. Additionally, 33% and 16% reached 20/12.5 in these groups, respectively. Postoperative CDVA was CDVA was equal to or better than preoperative levels in 98% of the ≤ 0.75D group and 95% of the > 0.75D group (P < 0.05). No significant overcorrection or undercorrection was observed. There were significant differences in vertical coma between preoperative and postoperative values in both groups (all P < 0.05), while there was no significant difference in other higher-order aberrations (P > 0.05). CONCLUSION: Ray-Tracing Guided-LASIK surgery is safe and effective. Compared with the preoperative BCVA, it can achieve better postoperative UDVA and effectively avoid the introduction of HOAs. In addition, for cases in which the MRSE difference between the two preoperative examination methods is ≥ 0.75, surgical design parameters adjustment can achieve ideal postoperative results.