New lens gets results
Dual-element lens retains accommodation up to two years in clinical study
A novel accommodative intraocular lens (AIOL) retained significant objective and subjective accommodative power at 12 and 24 months after surgery, reported Jorge Alió MD, PhD, presenting at the American Academy of Ophthalmology 2017 Annual Meeting in New Orleans, USA.
The Lumina AIOL (Akkolens, Breda, the Netherlands) consists of two progressive optical elements that change its focal power by moving across each other in a plane perpendicular to the optical axis. Implanted in the sulcus through a 2.8mm incision using a special injector, the lens’ haptics directly contact the ciliary muscles. When the ciliary muscles contract, they move the two elements in opposite directions. The effect can clearly be seen on ultrasound images after implantation.
The sulcus placement avoids problems with transferring ciliary muscle movement to the lens often encountered with accommodative lenses placed in the capsular bag. Capsule shrinkage and fibrosis in the weeks after surgery often reduces accommodative amplitude. Data from Dr Alió’s ongoing prospective clinical study suggest that the Lumina design works as intended for at least 25 months.
The study compared objective and subjective accommodation of 59 eyes of 43 patients implanted with the Lumina AIOL to 23 eyes of 15 patients implanted with monocular Alcon Acrysof SA60AT IOLs (Alcon) and 25 young phakic subjects. Objective accommodation was measured by the Grand Seiko WAM-5500 autorefractor.
At 12 months’ follow-up, the median subjective defocus curve of Lumina patients was above 0.8 decimal visual acuity, or about 20/25, from -2.5D to +0.5D, an accommodative range of about 3.10D, peaking at 1.0 VA over a -2.0D range, 2.0D to 0.0D. By comparison, in monofocal IOL patients, median defocus was above 0.8 VA from -0.5D to +0.5D for an accommodative range of -1.0D, with a sharp peak of 1.2 VA. The young phakic control was above 0.8 VA from -6.0D through +0.5D for an accommodative range of more than 6.5D, peaking at 1.2 VA from -2.0 to 0.0D.
Objectively, the Lumina group showed significant accommodation, demonstrating a median refraction of -0.38D±0.39 under -2.0D stimulation and -0.73D±0.53 under -2.5D and -3.0D stimulation. By comparison, the monofocal group showed virtually no accommodation, with a median of 0.17D±0.18 under -2.0D stimulation, 0.22D±0.15 under -2.5D stimulation and 0.17±0.14 under -3.0D stimulation.
At 24 months’ follow up, the differences in the defocus curve and the objective accommodative results between the 14 monofocal and the 17 Lumina patients remained unchanged.
Dr Alió concluded that both the objective and subjective measures of accommodation showed statistically significant differences between Lumina and monofocal IOL groups. At least 2/3 of the optical power change was explained by the WAM data. Different types of defocus curves were observed in the Lumina patients, which shows variability of outcome, he added.
Jorge Alió: email@example.com