Technique provides separation
Suturing the IOL to the sulcus provides the maximum separation from sensitive iris tissue and the corneal endothelium. There is no angle or trabecular involvement and no distortion of the pupil.
But scleral suturing is time consuming and demanding, and it can require a large incision. Potential suture exposure can lead to endophthalmitis, and late suture breakage can lead to IOL dislocation, said Dr. Garg.
He cited a recent study of 82 patients with scleral sutures. In a mean follow-up time of 83 months, 30.5% had ocular hypertension, 6.1% had suture breakage, 11% had suture exposure, 4.9% had retinal detachment (RD), 7.3% had cystoid macular edema (CME), and 3.17% had persistent elevated intraocular pressure (IOP).
“There have been a number of studies showing that sutures last 7-10 years and then have a higher chance of breaking,” said Dr. Garg. “In a 40- to 50-year-old patient, you’re pretty much assuring they’re going to need another surgery. If you’re not depending on the longevity of the suture, you have a better chance of a once-and-done surgery.”
The keys to Dr. Garg’s acceptance of scleral tunnel fixation are the low rate of complications and the tunnel, not the glue, that are responsible for long-term stability. He added that studies with high-speed videography have shown that unlike iris- and scleral-sutured IOLs, scleral-tunnel IOLs have minimal phacodonesis.