Scleral-Fixated IOLs

Recent Advances and Current Challenges in Suture and Sutureless Scleral Fixation Techniques for Intraocular Lens: A Comprehensive Review

Sun H, Wang C, Wu H¹

Industry support for this study: None

Abstract Summary

This comprehensive review examined the evolution of scleral-fixated IOL surgery and summarized contemporary sutured and sutureless fixation techniques used in eyes with inadequate capsular support. The review addressed traditional transscleral fixation methods; flapless approaches; knotless techniques such as the Z-suture; and modern sutureless procedures, including glued IOL fixation, the Yamane technique,² and the Canabrava double-flanged method.³ The advantages and shortcomings of each approach were highlighted.

Sutured fixation techniques remain widely used because of their versatility and familiarity. Long-term concerns with these techniques include suture erosion, knot exposure, late suture degradation, and IOL dislocation. Sutureless fixation methods avoid many suture-related complications and often reduce surgical time and tissue manipulation, but they may introduce new challenges, including haptic exposure, IOL tilt, IOL decentration, and uncertainty about long-term stability.

Discussion

A transformation in secondary IOL implantation has occurred during the past 2 decades, with ophthalmologists transitioning from large-incision procedures requiring scleral flaps and external knots to minimally invasive techniques designed to achieve stable fixation while reducing surgical trauma. A key message of this review was that no single fixation strategy is ideal for every eye. Surgical decision-making should be individualized based on the patient's ocular anatomy, the surgeon's experience, the available instrumentation, and the underlying cause of aphakia or lens instability. Although newer sutureless approaches have gained popularity, many surgeons continue to rely on sutured fixation because of its predictability and long-term track record.

The review also underscored the growing importance of dedicated fixation-specific IOL designs and biomechanical studies evaluating lens stability. Future innovations will likely focus on improving haptic fixation, minimizing postoperative IOL tilt, and enhancing long-term IOL centration while simplifying surgical execution.

Biomechanical Assessment of Intraocular Lens Stability and Position Based on Suture and Inlet Variations in the Canabrava Double-Flanged Technique

Suh YK, Choi S, Yoon CK, et al⁴

Industry support for this study: None

Abstract Summary

This laboratory-based experimental study evaluated the biomechanical performance of the Canabrava double-flanged fixation technique³ using anatomically scaled 3D-printed eye models. The influence of suture type, flange-to-flange suture length, and scleral outlet angle on IOL positioning and fixation stability was examined. Three suture materials and two suture lengths were analyzed. IOL tilt and optic-haptic distance were measured using image analysis software, whereas fixation stability was assessed through mechanical displacement testing.

IOL tilt was found to be influenced primarily by suture length rather than suture material. Longer sutures resulted in greater lens tilt, whereas displacement force and optic-haptic distance showed minimal variation across materials. The scleral outlet angle had little measurable effect on overall fixation stability.

Discussion

The Canabrava technique can be an appealing alternative to traditional scleral fixation because it can provide stable IOL fixation without scleral flaps, knots, or glue. The technique's growing popularity notwithstanding, objective biomechanical data on it are limited. The findings reported by Suh et al suggest that surgical precision may be more important than suture material selection. Excessive flange-to-flange suture length had the potential to increase lens tilt, which can affect optical performance and patients' postoperative visual quality. Conversely, the choice of suture material had relatively little impact on fixation strength.

The study also highlighted persistent concerns about iris chafing and pigment dispersion, complications that may be influenced not only by fixation technique but also by IOL design and optic-haptic geometry. The study results underscored the importance of careful patient selection and meticulous surgical planning, particularly for eyes that are predisposed to pigment-related complications.

Although experimental models were used rather than human eyes, the study provided valuable biomechanical insights that may guide the refinement of double-flanged fixation strategies and inform future clinical investigations.