Abstract: Objective To observe the clinical efficacy of viscoelastic free implantable collamer lens (ICL) implantation assisted with a new type crystal adjuster. Design Retrospective case series. Participants 142 eyes of eighty-one patients who have done ICL V4C lens implanted surgery in Huzhou Aier Eye Hospital. Methods 142 eyes were divided into two groups: group of applied with viscoelastic (viscoelastic group, 72 eyes), and group of applied without viscoelastic (viscoelastic free group, 70 eyes). Intraocular pressure was measured before operation, and 2, 4, 6 hours, 1 day, 1 week, 1 , 3 , 6 months after operation; corneal endothelial cell count, corneal endothelial hexagonal cell ratio, vault height, and uncorrected visual acuity (UCVA) were measured before operation, and 1 week, 1, 3, 6 months after operation. The operation time were recorded during the operation. The differences of the above indicators during and after the operation were compared between the two groups. Main Outcome Measures Operation time, corneal endothelial cell count, corneal endothelial cell hexagonal cell ratio, vault height, UCVA, and intraocular pressure. Results The operation time of the viscoelastic free group and the viscoelastic group was 9.91±1.75 minutes and 18.90±8.93 minutes, respectively (t=-7.658, P<0.01). There was no significant difference in postoperative UCVA and postoperative vault height between the two groups. At 2, 4 hours after operation, the intraocular pressures of the viscoelastic free group and the viscoelastic group was (15.61±3.24) mmHg, (14.41±3.38) mmHg and (20.68±5.33) mmHg, (18.26±4.71) mmHg, respectively (All P<0.001); at 6 hours after operation, the intraocular pressures of the viscoelastic free group and the viscoelastic group was (14.48±3.54) mmHg and (16.59±4.05) mmHg, respectively (P=0.003). There was no significant difference in corneal endothelial cell counts between the two groups postoperatively. Conclusion The ICL implantation without viscoelastic agent assisted by the new lens positioner is safe and effective. It simplifies the process of surgery and reduces the high intraocular pressure caused by viscoelastics. (Ophthalmol CHN, 2023, 32: 240-244)

Key words: posterior chamber intraocular lens implantation with lens, viscoelastic free, intraocular pressure