Comparison of horizontal and vertical intraocular lens fixation in the flanged intrascleral haptic fixation technique

PURPOSE: To compare the effect of fixation of the intraocular lens (IOL) in horizontal (H) and vertical (V) planes on visual outcomes in the flanged intrascleral haptic fixation technique. SETTING: Yozgat City Hospital, Yozgat, Türkiye. DESIGN: Retrospective study. METHODS: This retrospective study was conducted in 64 eyes of 64 patients (Group H: 38, Group V: 26). Surgical indications were aphakia and single-piece or 3-piece IOL subluxation. The reference points for fixation were the 3 and 9 o'clock quadrants for Group H and the 6 and 12 o'clock quadrants for Group V. Preoperative, intraoperative, and 6-month postoperative data of all participants were analyzed. RESULTS: Both groups had significantly increased visual acuity at postoperative 6 months (P < .05); however, no significant differences were found regarding postoperative 6-month visual acuity, refraction values, or lenticular astigmatism (P > .05). The groups also did not significantly differ in mean keratometry, anterior chamber depth, horizontal corneal radius, axial length, and intraocular pressure measurements (P > .05). Although there were no intraoperative or late postoperative (>3 months) complications (P > .05), a significant difference was noted for early postoperative (<1 month) complications, with conjunctival hyperemia occurring in 4 patients in Group V but no patients in Group H (P = .004). CONCLUSIONS: Intrascleral haptic fixation in horizontal and vertical planes had similar efficacy and safety in visual acuity, refractive outcomes, anterior segment parameters, and IOL centralization. Although conjunctival effects were more common in Group V, there were no significant differences in other complications. Therefore, both planes may be preferred as alternative quadrants in this technique.