Eyeworld

EW CATARACT 68 February 2018 by Stefanie Petrou Binder, MD, EyeWorld Contributing Writer Proof of stable, long-term intraocular lens fixation has generated a strong interest in scleral tunnel fixation among experienced cataract and refractive surgeons D ifferent approaches have been taken over time to secure IOLs in the absence of capsular support, each with its own set of compli- cations and learning curves. Scleral tunnel IOL fixation is emerging as an attractive and reliable option, thanks to much trial and error, and ultimately the promise of IOL posi- tional integrity. Speaking at the 2017 ASCRS• ASOA Symposium & Congress, Sumit Garg, MD, vice chair of clinical ophthalmology and med- ical director, Gavin Herbert Eye Institute, University of California, Irvine, California, told ophthalmic surgeons that with respect to stable IOL fixation, scleral tunnel fixation is a gratifying technique, which al- though challenging at first, is worth the extra effort. Challenging at first "This is not necessarily an easy surgery," Dr. Garg said. "It may at first seem difficult, however, the results have the potential of better long-term stability and therefore are worth the effort. The potential benefits outweigh the learning curve for this technique." Scleral tunnel/glued haptic fixation offers some advantages, most importantly that of solving long-term suture degradation issues. While tissue glue is used to seal the sclerostomies and provide short- term stability, scleral compression of the haptics creates permanent stability over time. The essence of this technique's long-term stability lies in the tunneling of the haptics into the sclera. "Scleral tunnel fixation avoids late suture breakage seen with su- tured PC IOLs," Dr. Garg said. "The key factor that gained my accep- tance of this technique was hearing that other surgeons were not report- ing late complications. Also, it was the realization that it is the tunnel, not the glue, that is responsible for long-term stability. Although we call it a glued IOL, the glue goes away within the first few days after surgery, and it is more the intrascler- al haptic fixation that allows for the stability of the lens." Acapsular IOL fixation options IOL fixation options in the absence of capsular support include: AC IOL, iris sutured IOL, scleral sutured IOL, and intrascleral haptic fixation of the IOL (glued and Yamane tech- niques). While iris fixated IOLs have the advantages of no scleral/conjuncti- val surgery, small self-healing inci- sions, and foldable IOLs with small incision insertion, compared to the more traditional PMMA lenses that require large incisions for insertion into the eye, they are limited to eyes with normal iris anatomy, can cause frequent pupil ovaling, pseudopha- kodonesis, and have a potential for iris chafing. Scleral sutured IOLs have the benefit of fixation in the best loca- tion within the eye, apart from the capsule itself. They offer maximal separation from the sensitive iris tissue and corneal endothelium, no angle or trabecular involvement, and no distortion of the pupil. How- ever, this mode of fixation is time consuming and technically demand- ing, requires large incisions, has the potential for suture related risks over time like suture exposure, has been linked with endophthalmitis, and is associated with late suture breakage and IOL dislocation. Dr. Garg elucidated that iris and scleral sutured IOLs move against their sutures, resulting in some movement of the IOL within the eye and possibly associated with an increased rate of suture breakage. According to one study in 82 eyes of 72 patients receiving scleral sutured IOLs who were followed for a mean 83 months (range: 7–167 months), suture breakage was noted in about Cataract surgeons turn to scleral tunnel fixation for reliable IOL placement Presentation spotlight Mark 180 degrees apart centered on corneal apex Mark 2 mm posterior to limbus Externalize haptics using 23-g microforceps

• Blank Page
• Blank Page (1)