We are developing an accommodative - disaccommodative intraocular lens implant (ADIOL) system based on a novel concept of capturing zonular tension and transmitting it unimpeded to a dynamically position intraocular lens system. This is made possible by a zonular capture haptic (ZCH) apparatus. This apparatus lends itself equally well to several possible combinations of optics. Such optics can be rigid, single or double optics, moving axially, or flexible optics that can change the radius of curvature. Depending on the optic(s) chosen for the system, it is anticipated that a range 3.5-9.0 diopters of accommodation can be obtained. Traditional non accommodative IOL's and all attempted accommodative IOL's attempt to preserve as much of the integrity of the capsular bag as surgically possible and fixate the IOL within this bag. The accommodative models rely on the inherent, presumed elasticity of the capsule to allow alteration in the shape of the IOL that leads to a change in dioptric power. Our method is based on the observation that the capsular bag contracts around the IOL and becomes unyielding within weeks of cataract surgery, as a result of biological changes induced by surgery. The bag becomes a rigid, fibrosed and devitalized disc, encompassing the IOL and restricting its movement. The rigidity of the capsular disc encompassing the IOL prevents accommodation. Our ZCH remedies the capsular disc rigidity and allows for unrestricted freedom of movement and unimpeded force transmission to the ADIOL. We have already shown that our ZCH mimics and parallels the movement of the ciliary body in our preliminary data. Our goals are to show that we can translate this haptic movement into anterior posterior optic movement and thereby produce accommodation. Further, we plan to explore modifying the ZCH to a mechanical locking haptic that would allow all the steps to be completed at one surgical sitting. This Phase I data is fundamental to engineering the haptic-optic system that can produce the accommodative range required under the restrictions of forces and amplitude of displacement present in the living eye.
We are perfecting a zonular capture haptic apparatus, refining the surgical steps for its successful implantation and activation and obtaining precise measurements of the amplitudes of movement exerted by zonules during disaccommodation, in vivo, in an experimental model of accommodation in adult Rhesus monkeys. This will provide the scientific basis for to engineer an effective accommodative-disaccommodative intraocular lens implant in Phase II of research. Such a successful device would represent a surgical cure for both presbyopia and an alternative for non presbyopic refractive surgery.
