Intraocular photobonding to enable accommodating intraocular lens function

Abstract

Purpose: Accommodating intraocular lenses (A-IOLs) require capturing the ciliary muscle forces. Prior work demonstrated strong photo-initiated bonding between strips of capsular bag and poly(2-hydroxyethyl methacrylate); (pHEMA) polymer in an extraocular setting. We demonstrate that photobonding can be achieved intraocularly. Methods: Phacoemulsification was performed in porcine eyes (<24 hours postmortem). A commercial intraocular lens (IOL; pHEMA-MMA material) was inserted in the capsular bag. Surface contact between the lens and capsular bag was ensured by continuous air infusion into the anterior chamber of the eye, which provided sufficient pressure at the interface, as well as oxygen. The capsular bag and IOL then were stained with 0.1% photosensitizer Rose Bengal (RB) solution. A fiberoptic probe connected to a diode-laser (532 nm) was used to locally irradiate the capsular bag–IOL interface intraocularly. The bonding breaking load was evaluated in a uniaxial stretcher. Results: Photobonding occurred in the 0.8 to 1.6 W/cm irradiance range and 2.5 to 7 minutes irradiation time. Average forces of 0.12 N stretched but did not break the bond. These forces, applied uniaxially, are higher than the summed net accommodating force of the ciliary muscle along the entire equator (0.08 N). In two cases, the zonulae broke before the bonded region. Conclusions: Photobonding between the capsular bag and IOL polymer can be achieved intraocularly, in a procedure compatible with standard cataract surgery. This technique will enable the mechanisms of A-IOLs not to rely on capsular bag integrity or natural haptic fibrosis. Translational Relevance: Intraocular photobonding holds promise to enable operation of A-IOLs to restore accommodation in presbyopia, affecting 100% of the population <45 years old. Intraocular bonding of polymer material to ocular tissue also may find other applications in ophthalmology.