Electromechanical Cornea Reshaping for Refractive Vision Therapy - PROJECT SUMMARY The cornea is a transparent, highly organized structure of the anterior eye that is responsible for most of the refractive power of the eye. The corneal stroma consists of orthogonally stacked collagen-fibril lamellae whose molecular composition and precise macromolecular geometry eliminate backscattered light and maintain the shape of the cornea. Anatomical variation, birth defects, trauma, and various pathologies can alter the shape, structural stability, and transparency of the cornea, thus affecting vision. Surgical interventions to treat myopia, hyperopia, and astigmatism include laser-assisted in situ keratomileusis (LASIK) and photorefractive keratotomy (PRK). Despite their popularity, these procedures are expensive ($1,500 - $3,000 per eye), permanently lower the biomechanical stability of the cornea, and pose some risk of surgical complications and ectasias. We have been working on an electrochemical device platform, electro-mechanical reshaping (EMR), for remodeling cartilage and other collagen-rich tissues, and propose to develop that technology as a low-cost alternative to laser-based vision correction. EMR relies on short electrochemical pulses to electrolyze water, with subsequent diffusion of protons into the extracellular matrix of collagenous tissues; protonation of immobilized anions within this matrix disrupts the ionic-bonding network that provides structural integrity. This leaves the tissue transiently responsive to mechanical remodeling; subsequent re-equilibration to physiological pH restores the ionic matrix, resulting in persistent shape change of the tissue. Pairing EMR with a customizable corneal reshaping contact lens thus offers the possibility of a molecular-based method to alter corneal curvature that does not require ablation of the native stromal tissue.
