JAN 10, 2012
The authors describe an additional method to secure a sulcus-based IOL to the remnant capsule or a capsular membrane. The technique, which the authors have termed “capsule membrane suture (CMS) fixation,” involves suturing the IOL haptics to the fibrotic elements of the capsular membrane to center and secure the IOL to the capsular membrane and prevent complications associated with uveal touch. I think this is a very valuable technique since it can be done through paracentesis only, prevents movement of the lens and avoids issues of uveal contact and iris distortion.
It was successfully used in three eyes of two patients where membrane optic capture was impossible. All eyes achieved excellent centration and stability of the IOL at six months, and there were no intraoperative or postoperative complications. In all cases, patients reported subjective improvement in the quality of their vision, and there was no change in BCVA. The IOP remained within the reference range postoperatively in all three eyes. The anterior segment was quiet in all three eyes within one month of surgery, and there were no signs of uveitis-glaucoma-hyphema syndrome at six months.
Compared with scleral fixation of IOLs, the authors write, CMS fixation is simpler and easier to perform. The IOL haptics are sutured to the capsule, minimizing decentration and tilt, suture erosion through the sclera and the risk of intraocular hemorrhage. Fixating the lens to the capsule also prevents the possible adverse effects of a sulcus-placed lens like iris chafing causing iris transillumination defects, uveitis-glaucoma-hyphema syndrome or sunset syndrome. Most important, the sutures are safer and simpler to complete because they are entirely intraocular and they are placed in avascular tissue. This reduces the possibility of infection, erosion or granuloma formation compared with a scleral-fixated lens.
The authors emphasize the importance of adequate zonular support, since CMS fixation relies on an intact zonular apparatus. The presence of phacodenesis, iridodonesis or IOL tilt must be carefully noted preoperatively and at the time of surgery. If capsular/zonular support is compromised, the surgeon must be prepared to consider other options, including IOL exchange with an anterior chamber IOL or an iris or scleral-sutured IOL. Similarly, the possibility of intraoperative cheese wiring of the capsule may persuade the surgeon to abandon CMS fixation in favor of other IOL fixating techniques.
Although more studies are needed to evaluate long-term outcomes, this technique is a valuable tool for stabilizing IOLs in these challenging cases.