Scleral-fixated intraocular lens implants—evolution of surgical techniques and future developments

Abstract

Varied options are available for the implantation of secondary intraocular lens implants in the absence of zonular or capsular support. Loss of the capsule can occur in the context of complicated cataract surgery, trauma or inherited conditions such as Marfan syndrome or pseudoexfoliation. Approaches to overcome this include optical measures such as the use of spectacles or contact lenses, and surgical therapy incorporating the use of anterior chamber, iris-fixated or scleral-fixated lenses. Surgical techniques to implant scleral-fixated lenses have undergone various modifications, since the first publication of sutured intrascleral fixation described in the 1980s. However, despite the advances in surgical techniques, studies are limited either by their retrospective nature, small sample size and most importantly small duration of follow-up. This comprehensive review aims to amalgamate the evolution of various surgical techniques with regards to intrascleral lens fixation and suggests areas for future development.

The Link between Anterior Scleral Thickness, Corneal Biomechanical Response, and Ocular Parameters

“…Enhancing knowledge on AST measurements by advanced imaging technics and their correlations with ocular variables is of particular importance given the association of scleral features with diseases such as open angle glaucoma [31], scleritis and episcleritis [32], and myopia [17]. Moreover, the characterization of the AST profile might help in the planning and monitoring of ophthalmological surgery, such as scleral-fixated intraocular lenses [33], trabeculectomies [34], intravitreal injections, and glaucoma, as well as in monitoring the effect of glaucoma medical treatment [35]. Finally, the association of biomechanical corneal metrics with AST may be beneficial to better understand the implication of the sclera on corneal response, given its relevant role in the early diagnosis of keratoconus [9, 10], planning the type of refractive surgery and monitoring procedures that modify the scleral tissue, such as myopia progression and prostaglandin treatment in glaucoma.…”

Flapless and Conjunctiva‐Sparing Technique for Transscleral Fixation of Intraocular Lens to Correct Refractive Errors in Eyes without Adequate Capsular Support

“…As a flange created by thermos-cauterization is the key point of the technique, certain types of IOLs, whose haptics are made from materials that cannot be reshaped by thermos-plasticity, are impractical for this technique [ 16 , 17 ]. Transscleral-sutured fixation remains a vital method to fixate IOLs; compared with anterior chamber IOL and iris-fixated IOL, it places an IOL closer to the original crystalline lens and has the advantages of lower demand for corneal endothelium, iris structure, and angle status [ 4 , 6 ]. Furthermore, compared with the flanged method, transscleral-sutured fixation is suitable for a broader range of IOL types.…”

“…Implanting a posterior chamber IOL via a scleral-fxated method has several inherent advantages over other techniques, allowing the implanted IOL to be positioned closer to the original crystalline lens with a reasonable distance from anterior segment structures. Transscleral-sutured fxation, a commonly performed scleral-fxated technique, typically requires the large opening of conjunctival tissues and the creation of scleral faps to bury the suture ends and knots [6][7][8]. Te most commonly used 10-0 polypropylene in sutured-fxation methods is prone to loosening and breakage, leading to IOL tilt, decentration, or even up to a dislocation rate of 18% to 28%, and thus the occurrence of signifcant postoperative refractive errors, of which IOL tilt angle larger than 15 °cannot be corrected with spectacles [9,10].…”

Complications of Secondary Scleral-fixated Intraocular Lens Placement

“…With any scleral-fixated IOL technique, common complications which typically resolve within 60 days include corneal edema, ocular hypertension, vitreous hemorrhage, and cystoid macular edema. Corneal edema is a very common complication across all techniques, with reports from 0.5% to 15.4% of cases 44,45. Ocular hypertension can occur after SFIOL surgery, prevalent in up to 30.5% of eyes 45.…”