Despite inadequate capsular support, several options available to fixate IOLs

Issue: January 10, 2012

ByRichard L. Lindstrom, MD

Richard L. Lindstrom

The best way to fixate an IOL in an eye with inadequate capsular support remains a topic of significant controversy.

In the 1980s, my first decade as a consultative corneal specialist at the University of Minnesota, I frequently encountered patients with iris-fixated and open-loop anterior chamber IOLs who developed a typical set of complications, including pseudophakic bullous keratopathy, uveitis, cystoid macular edema, hyphema and secondary glaucoma.

Along with my fellows of the time, including Steve Lane, Richard Duffey, David Hardten, Tom Lindquist and Jonathan Rubenstein, we worked on techniques of suture fixation of posterior chamber IOLs using suturing to the sclera. Starting with cadaver eye studies, we learned that the diameter of the ciliary sulcus is smaller than many had believed (averaging about 12.5 mm), opposite to the white-to-white measurement and shorter in the horizontal meridian. This resulted in the surface landmarks over the sulcus being closer to the limbus in the horizontal meridian, about 0.5 mm posterior, and further back in the vertical meridian, about 1 mm back.

We practiced suturing techniques in the laboratory and moved into patients, selecting 10-0 polypropylene as our preferred suture. It was a different era in which it was easier to innovate, and by the mid ’80s, working with Storz and Alcon, we developed two IOLs, the Storz P366UV and the Alcon CZ70BD, with large optics, appropriate lengths and suture fixation holes in the mid-haptic to allow easier suture fixation. These two IOLs remain commercially available today, 25 years later, so we are gratified they served a useful purpose.

The learning curve was interesting, but we became rapidly convinced that this was an excellent technique in combination with keratoplasty and later for IOL exchange prior to corneal decompensation. Combined with vitrectomy and intense anti-inflammatory therapy, many patients recovered significant vision with resolution of inflammation, cystoid macular edema, hyphema and glaucoma. Suture complications evolved early, including suture erosion to the surface, which another fellow, Frank Bucci, resolved while in training at Minnesota with the “Bucci button,” a small overlay partial-thickness corneal button placed over the eroding suture.

Unexpected to all, at about 15 years postoperative, some patients presented with IOL subluxation from suture degradation/breakage. We learned that 10-0 polypropylene was not as permanent as we had hoped. This discovery has lead to a search for a better way to fixate a posterior chamber IOL to the sclera. Some, including our group, have turned to larger diameter polypropylene and/or other suture materials, including Gore-Tex and polyester. Others, including my extraordinarily innovative friend Amar Agarwal, have developed techniques for the direct fixation of the IOL haptics to the sclera. This technique has a set of technical challenges of its own, but it eliminates the possibility of late suture degradation or breakage. This makes it especially attractive in the younger patient in whom a scleral-fixated IOL is selected as the best option.

I expect this technique to gain popularity as a valid alternative for these complex patients, but a careful study of the intraocular maneuvers required, including a more extensive vitrectomy, preferably through the pars plana, and a bi/tri-manual handoff technique of the haptics present the surgeon with some intraocular surgical challenges.

Of course, iris fixation remains a valid option for many patients and surgeons, and I still use an anterior chamber IOL in select cases. Following the literature as an especially interested participant in this field, including a prospective multicenter clinical trial in the VA hospital system, I find no solid evidence that unequivocally supports one option over another. For me, suture fixation of a posterior chamber IOL to the sclera or iris or directly glued into place, as well as placement of an anterior chamber IOL, all remain valid approaches to fixate an IOL in the face of inadequate capsular support. Each approach has a set of required surgical skills and a learning curve, so a reasonable volume of complex cases is required to become expert. Fortunately, many videos, articles and textbook chapters are available to help the interested surgeon, as well as direct observation of experienced surgeons in their own operating suites.

Disclosure: Dr. Lindstrom has no personal commercial interest in the Storz P366UV or the Alcon CZ70BD.