Haptic design lets microincision lens be implanted through 1.8-mm incision

Lynda Charters

Somain, France-The new Akreos microincision IOL (Bausch & Lomb) with its new haptic design can be implanted without difficulty through a 1.8-mm incision, combining all the benefits of the Akreos design with those of smaller corneal incisions. The IOL provides good-quality vision and intracapsular stability, according to Thierry Amzallag, MD, who reported the 6-month results of a pilot study.

"Microincision techniques can be done through sub-2-mm incisions, but new IOLs are needed to maximize the benefits of the techniques," he said. "The currently available IOLs do not always behave as safely as do standard IOLs."

This prompted a study of the Akreos IOL, explained Dr. Amzallag, a high-volume surgeon in charge of cataract surgery at the Ophthalmic Institute of Somain in France.

The lens design also ensures stability in the bag. Its four haptics are composed of three parts:

"Importantly, the IOL also has been designed to resist the development of posterior capsular opacification (PCO) as the result of 11° angulated haptics and a 360° posterior barrier," he said.

Dr. Amzallag and colleagues conducted a single-center pilot study of the Akreos IOL in which the primary outcome was the size of the corneal incisions and the secondary outcomes were visual acuity and intracapsular stability. Twenty patients participated in this study. The maximum follow-up was 12 months.

In the first group of 10 patients, the investigators used a technique with the cartridge inside the anterior chamber. The mean incision size after injection of the IOL was 2.22 mm, and the minimal incision size after injection was 2.2 mm.

In the second group of 10 patients, the cartridge was not introduced into the anterior chamber, with the goal of achieving a smaller incision, he explained. The internal cartridge size must be the same as the incision size to achieve an isobaric injection of the IOL. In this second group, the mean incision size after injection of the IOL was 1.85 mm, and minimal incision size was 1.8 mm, according to Dr. Amzallag.

He reported that after the surgeons mastered the learning curve, the incision size decreased after injection from 2 to 1.8 mm for the last five cases performed.

"Early postoperative stability of the IOL was very good, with minimal decentration of the lens," Dr. Amzallag said. "There was a gain of six lines of uncorrected visual acuity (UCVA) with very good predictability of the refractive outcome."

The mean UCVA was 0.14 logMAR, and the best-corrected visual acuity (BCVA) was 0.03.

"There was a good early postoperative BCVA, and excellent stability of the visual acuity between 1 and 6 months postoperatively," he said. "The stability of the refraction over time was also very good between the same time points."

Dr. Amzallag explained that the investigators measured the lens stability versus the pupil by comparing the central axis of the optic and the central axis of the pupil at 2 weeks and 1, 3, and 6 months. At the latter three time points, there had been only minimal movement of the optic. The lens was very stable with only 0.1 mm of decentration of the optic at 6 months.

PCO was measured using EPCO 2000 software to analyze the central 3 and 6 mm on retroillumination images.