Intrastromal implant improves near vision
Patient satisfaction with outcomes, spectacle independence rates are high at 1 year
The implant is a doughnut-shaped, bifocal lens with a peripheral refractive zone (+1.25 to +3 D) and a central neutral zone that is implanted in the nondominant eye. Dr. Pallikaris, professor of ophthalmology, University of Crete, and director, Institute of Vision and Optics, Heraklion, Greece, presented outcomes from 12 months of follow-up for a series of 15 patients (mean age 51 years) who had the lens placed inside a corneal tunnel created using a femtosecond laser.
Consistent with the UCVA data, patient responses demonstrated excellent visual function. One hundred percent of patients gave ratings of excellent or good to questions about perceptions of their uncorrected near vision, distance vision in the operated eye, and binocular uncorrected distance vision. With a single exception, no patient used spectacles for reading, and the remaining patient reported wearing glasses for near activities less than 50% of the time.
"In addition to these very positive results, implantation of this novel lens has many advantages as a treatment for presbyopia," Dr. Pallikaris said. "The procedure is simple, minimally invasive, and takes only minutes to complete. Unlike LASIK, there are no flap-related concerns, and the device can be replaced or easily removed without adverse effects.
"In addition, the lens itself is invisible, and so there are no cosmetic issues or interference with fundus or slit-lamp exam," he said.
The implant is made of a hydrophilic polymer, measures 20 Ám in thickness with a diameter of 3 mm, and is implanted at a depth of 280 to 300 Ám.
"Due to the depth of the implantation, the procedure has a minimal effect on topography," Dr. Pallikaris said.
For the study Dr. Pallikaris presented, tunnel creation for lens implantation was performed using the proprietary femtosecond laser and software (iFS femtosecond laser with the iFlap or iPockets software, Abbott Medical Optics) and a special mask, although other femtosecond lasers can be used.