Relative position of the central hole after EVO-ICL implantation for moderate to high myopia

Abstract

Abstract Background This study aimed to evaluate the relative position of the central hole (CH) of EVO Implantable Collamer Lens (EVO-ICL), the pupil center (CP), and the corneal center (CC) after implantation of EVO-ICLs for moderate to high myopia. Methods Eighty-nine eyes of forty-seven patients with moderate to high myopia were evaluated. The mean preoperative spherical equivalent (SE) was − 12.58 ± 4.13D. A routine postoperative follow-up was performed within 1 ~ 12 months. Positions of the CH of EVO-ICLs, the CP and the CC were recorded using a slit lamp anterior segment photography system, and their relative distances were calculated with the Visio image analysis software. Results All surgeries were performed safely, and no complications were observed in follow-ups 4.3 ± 4.82 months after surgery. At the last follow-up, the safety index (postoperative CDVA/preoperative CDVA) was 1.23 ± 0.48, and the efficacy index (postoperative UDVA/preoperative CDVA) was 1.08 ± 0.31. The CH in 85 eyes (95.51%) was superior to the CC, with 47.19% (42/89) on the temporal side and 48.31% (43/89) on the nasal side. The CH in 84 eyes (94.38%) was located on the temporal side of the CP, with 56.18% (50/89) superior and 38.2% (34/89) inferior to the CP. The CP of 85 eyes (95.51%) was superior on the nasal side of the CC. On the defined x-axis, the average distance from the CH to CC was significantly shorter than the average distance from the CP to CC (p < 0.001). Conclusions An imperfect match between the central hole of EVO-ICLs and the pupil center does not necessarily indicate ICL dislocation. Compared to the pupil center, the position of the central hole of EVO-ICL is closer to the corneal center.