IC-8 study in post-LASIK cases
Small aperture IOL provides post-refractive surgery patients with good spectacle independence
Josh Cuthbertson MB ChB
Unilateral implantation of the IC-8 (Acufocus) small-aperture IOL seems to be a safe and effective option for providing spectacle independence in cataract patients who have undergone previous laser vision correction, reports Josh Cuthbertson MB ChB, University Hospital Ayr, Ayr, Scotland UK.
Speaking at the 24th ESCRS Winter Meeting in Marrakech, Morocco, Dr Cuthbertson presented the results of a prospective interventional case series in which 11 cataract patients with a history of corneal laser refractive surgery underwent implantation of the IC-8 small aperture lens. The mean uncorrected visual acuity at six months follow-up in the eye with the implant was 0.01 logMAR for distance, -0.16 logMAR for intermediate and N5 (0.2 logMAR) for near vision. Some 90% of patients achieved spectacle independence. In addition, there were no intraoperative or postoperative complications.
He noted that all patients in the study underwent optical biometry, Placido-based topography and dual Scheimpflug tomography (GALILEI). The ASCRS post-refractive surgery online calculator was used for IOL power calculation and aimed for a mild myopia of -0.75D. The mean absolute error (MAE) was 0.7D.
The IC-8 lens is based on the same pinhole lens optical principle as the Kamra (Acufocus) corneal inlay and is designed to provide an increased depth of focus compared to a standard spherical IOL. Initial studies and case reports relating to corneal pinhole inlays for the correction of presbyopia in patients with previous LASIK are promising. However, studies investigating unilateral small aperture IOL implantation in LASIK-treated eyes for treatment are limited, Dr Cuthbertson said.
“Unilateral implantation of a small aperture IOL in eyes with prior laser vision correction is safe and will achieve spectacle independence postoperatively in most patients. Aiming for a mild myopia in the non-dominant eye enhances the uncorrected intermediate and near vision without compromising on the distance visual acuity,” he added.
In the discussion that followed Dr Cuthbertson’s presentation, session co-chair Béatrice Cochener-Lamard MD, PhD, asked what implant the fellow eye should receive. In reply, Dr Cuthbertson’s co-author Sathish Srinivasan FRCSEd, FRCOphth, FACS , also at University Hospital Ayr, noted that similar results to those of the present study have been achieved with bilateral implantation of the IC-8 small aperture lens.
He also cited a study by Burkhard Dick MD, Bochum, Germany, which compared patients receiving the IC-8 in one eye to patients receiving the TECNIS® Symfony EDOF (Johnson & Johnson) lens in both eyes. It showed that intermediate vision was slightly better in patients with the Symfony IOL but both lenses provided equivalent results regarding distance and intermediate vision.