A Comparative Study on the Early effects of ICL and FS-LASIK on Binocular vision function and Higher-order aberrations

Objective To compare and characterize the dynamic changes in accommodation, vergence, and higher-order aberrations in patients with moderate to high myopia undergoing implantable collamer lens (ICL) implantation and femtosecond laser–assisted laser in situ keratomileusis (FS-LASIK), so as to provide an evidence base for postoperative visual function training and to inform more rational surgical decision-making for myopic patients. Methods This was a prospective, non-randomized controlled study. A total of 63 patients (126 eyes) with moderate to high myopia, treated at the Army Specialty Medical Center between May 2025 and November 2025, were enrolled. Eligible subjects were 18–35 years of age, had a spherical equivalent of −6.00 D to −10.00 D, and a preoperative best-corrected visual acuity (BCVA) of ≥0.8. Binocular visual function and higher-order aberrations were assessed using standard clinical tests and the OPD-Scan III system at four time points: preoperatively and at 1 week, 1 month, and 3 months postoperatively. Binocular vision testing included amplitude of accommodation, binocular accommodative facility, positive and negative relative accommodation, heterophoria, accommodative convergence/accommodation (AC/A) ratio, binocular cross-cylinder (BCC), and positive and negative fusional vergence. Higher-order aberration measurements comprised total ocular HOAs, coma, trefoil, and spherical aberration. Parameters related to accommodation, vergence, and higher-order aberrations at each time point after ICL and FS-LASIK were subjected to statistical comparison and longitudinal analysis. Results In the ICL group, mean spherical equivalent (SE) at 1 week, 1 month, and 3 months postoperatively was significantly improved compared with preoperative values (p < 0.001). The amplitude of accommodation showed an initial postoperative decrease followed by recovery toward baseline (p < 0.01), and PRA exhibited a similar pattern of early reduction with subsequent return to preoperative levels (p < 0.01). By 3 months, binocular accommodative facility was significantly higher than before surgery (p < 0.01). Both distance and near exophoria were markedly reduced after ICL implantation (p < 0.01 for both). Distance base-in (BI) break and recovery points were significantly lower postoperatively than at baseline (both p < 0.01), and near BI break and recovery points were also significantly decreased at all postoperative time points (both p < 0.01). In contrast, distance base-out (BO) break and recovery points were significantly higher at each postoperative visit than preoperatively (both p < 0.01). Total ocular higher-order aberrations (HOAs) increased significantly after surgery (p < 0.05). Trefoil aberration rose initially and then declined toward preoperative levels (p < 0.01), whereas spherical aberration increased significantly and remained elevated at 3 months (p = 0.003). In the FS-LASIK group, mean SE at 1 week, 1 month, and 3 months postoperatively was also significantly better than preoperative SE (p < 0.001). Pairwise postoperative comparisons showed that mean SE at 3 months was significantly lower (i.e., closer to emmetropia) than at 1 week. The amplitude of accommodation again decreased initially and then recovered toward baseline (p < 0.01), and PRA followed the same trend, with a significant early decline and subsequent return to preoperative levels (p = 0.017). Binocular accommodative facility at 3 months was significantly improved relative to baseline (p < 0.05). Distance and near exophoria were both significantly reduced after FS-LASIK (p < 0.01 for each). Postoperative distance BI break and recovery points were significantly lower than preoperative values (both p < 0.01), and near BI break and recovery points were likewise significantly reduced at all postoperative time points (both p < 0.01). Distance BO recovery points were significantly higher after surgery than at baseline (p = 0.038). Total ocular HOAs increased significantly following FS-LASIK (p < 0.001), and coma, trefoil, and spherical aberration were all significantly higher postoperatively than preoperatively (all p < 0.01); among these, coma and spherical aberration at 3 months were significantly greater than at 1 week. In between-group comparisons, residual SE at 1 week was higher in the FS-LASIK group than in the ICL group, whereas at 1 month the positive BCC value was greater in the ICL group than in the FS-LASIK group. At 3 months, total ocular HOAs, coma, and spherical aberration were all significantly higher in the FS-LASIK group than in the ICL group (p < 0.01 for all comparisons). Conclusion Both ICL implantation and femtosecond FS-LASIK are effective treatments for the correction of myopic refractive error. In the early postoperative period, patients may experience transient changes in accommodative and vergence function; however, these typically return to preoperative levels over time, with some patients even showing improvement. Compared with FS-LASIK, ICL implantation provides greater stability and predictability of postoperative refractive status and induces fewer higher-order aberrations.