Add-on sulcus-based IOL addresses ametropia post-cataract surgery

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Kenneth J. Rosenthal, MD, explains the advantages of an add-on sulcus-based IOL for correcting refractive errors in eyes that have undergone cataract surgery with in-the-bag IOL implantation.

By Cheryl Guttman Krader; Reviewed by Kenneth J. Rosenthal, MD

Great Neck, NY-A review of reports in the published literature together with an analytical review of design features and personal clinical experience supports the use of an add-on sulcus-based IOL (Sulcoflex, Rayner) as a better option than IOL piggybacking using conventional “in-the-bag” IOLs for correction of refractive problems following cataract surgery, said Kenneth J. Rosenthal, MD, associate professor of ophthalmology at University of Utah Medical School, and in private practice in New York, in a scientific paper co-authored by Jacob Gohari, BA.

Although not approved by the FDA, the add-on sulcus-based IOL is available in many countries and Dr. Rosenthal has used it at his center, Rosenthal Eye Surgery, Great Neck, NY, and at New York Eye and Ear Infirmary, New York, through an FDA compassionate use device exemptions.

“There are currently no IOLs approved by the FDA which are designed for implantation in the sulcus, and piggybacking of posterior chamber IOLs in the sulcus can cause a variety of complications, including pigmentary dispersion syndrome, elevated IOP, interlenticular opacification, and IOL decentration or tilt that can ultimately result in visual field loss and decreased visual acuity,” Dr. Rosenthal said.

“The concept of the add-on sulcus-based IOL is validated by a number of peer-reviewed studies,” he added. “It produces stable, predictable outcomes and avoids or mitigates the problems seen with piggybacking conventional IOLs. Considering some of its benefits, perhaps the sulcus will be the place we put all IOLs in the future.”

He pointed out that historically the sulcus was used for IOL implantation, but that surgeons migrated to capsular bag fixation due to better centration of the IOL and better sequestration of the IOL from uveal tissue.

“With improved biocompatibility and the current Sulcoflex design, which provides excellent centration, we will most assuredly migrate back to the sulcus in the future,” Dr. Rosenthal said.

The add-on sulcus-based IOL portfolio comprises four models. In addition to a monofocal aberration-neutral aspheric lens for correcting postsurgery ametropia, there is a multifocal, a toric, and a multifocal toric version.

The lenses are made of a hydrophilic acrylic material (Rayacryl) that has a high uveal biocompatibility and so reduces the potential for iris inflammation.

Undulated, relatively large haptics (14-mm haptic to haptic length, to account for the sulcus diameter compared with the capsular bag) help to keep the IOL secure and properly oriented, thereby decreasing any potential for decentration and tilt. In addition, the haptics feature a 10° posterior angulation that helps the IOL maintain a safe distance from the iris and the primary IOL to minimize risk for iris pigment dispersion, iris chafing, and interlenticular opacification.

The add-on sulcus-based IOL optic has a concave-convex meniscus design that further enhances its vaulting over the primary IOL without central touch. With its 6.5-mm diameter, the optic is also larger than most primary, in-the-bag IOLs, and that reduces the potential for reduced optical performance should a small decentration occur. A round edge on the optic reduces dysphotopsia and also enhances biocompatibility, Dr. Rosenthal said.

Use of the sulcus-based IOL for correcting pseudophakic refractive error also has a benefit of easier reversibility compared with laser adjustment of IOL power or IOL exchange. Speaking from personal experience, Dr. Rosenthal noted that explantation of the add-on sulcus-based IOL is relatively atraumatic and was done successfully without any complications. He was able to exchange the Sulcoflex IOL in a patient who required subsequent LASIK enhancement in a highly aberrated cornea, and in which a hyperopic shift occurred.

In addition, he was able to explant it in a simple 2-minute procedure from a patient whose negative dysphotopsia did not diminish.

In his review of the literature, Dr. Rosenthal identified reports of cases where the add-on sulcus-based IOL was used to treat postsurgical ametropia.

Other uses include management of negative dysphotopsia, which is a problem Dr. Rosenthal has addressed using the add-on sulcus-based IOL, and to reduce spectacle dependence in patients with a monofocal lens seeking multifocality or toric correction.

Kenneth J. Rosenthal, MD

E: kr@eyesurgery.org

Dr. Rosenthal is a consultant to, speakers bureau member, and receives travel expenses from Abbott Medical Optics, Bausch + Lomb, and Rayner.