A comparison of visual outcome and rotational stability of two types of toric implantable collamer lenses (TICL) : V4 versus V4c

PURPOSE To compare the efficacy and rotational stability after implantation of two types of toric implantable collamer lenses (Toric ICL™(TICL);V4 and V4c, STAAR Surgical Co.). STUDY DESIGN Retrospective case series. METHODS This retrospective study evaluated total 48 eyes of 48 patients who underwent the implantation with V4 and V4c TICL with a central hole; A twenty-four eyes of 24 patients with V4 TICL and 24 eyes of 24 patients with V4c TICL with a central hole. Visual acuity, manifest refraction, and intraocular pressure were evaluated before and after surgery. Rotational stability (disparity between the intended axis and achieved axis) was assessed in both groups using digital anterior segment photographs, and vector analysis was also performed. RESULTS Uncorrected visual acuity improved in both groups without significant difference (P = .111). There were no statistical differences between two groups in postoperative SE and cylindrical errors (P = .067 and .384, respectively). The mean value of rotation was 4.17±3.31° and 3.39±2.36° in the V4 and V4c TICL groups, respectively without significant difference (P = .364). Vector analysis of astigmatic correction showed no significant diffrence between two groups. CONCLUSION V4 and V4c TICL have similar efficacy with regard to visual acuity and refractive outcomes and rotational stability.