Accommodating intraocular lenses and methods of use
View Patent ↗Accommodating intraocular lenses and methods of use. The accommodating intraocular lenses include peripheral regions that are adapted to be more responsive to certain types of forces than to other types of forces. For example, the accommodating intraocular lenses can include haptics that are stiffer in an anterior-to-posterior direction than in a radial direction.
1. An accommodating intraocular lens, comprising:
an optic portion comprising an optical axis and an optic fluid chamber; and
a haptic having a proximal portion secured to the optic portion and a free distal portion disposed away from the proximal portion, wherein a radially innermost surface of the haptic, relative to the optical axis, from the proximal portion to the free distal portion, follows a curved radially-outer peripheral surface of the optic portion, and
in a first cross section between the proximal portion and the free distal portion, the haptic has a first radially innermost wall radial thickness and a radially outermost wall thickness, the radial thicknesses measured orthogonal to the optical axis, and the radially innermost surface is directly adjacent the optic portion, the first inner wall radial thickness being greater than the radially outermost wall thickness, wherein the thicker inner wall radial thickness adapts the haptic to be more sensitive to capsular forces in the radial direction than to capsular forces in the anterior-to-posterior direction, and
in a second cross section closer to the proximal portion than the first cross section, the haptic has a second radially innermost wall radial thickness less than the first radially innermost wall radial thickness and the radially innermost surface is radially further from the optic portion than in the first cross section, the haptic comprising a haptic fluid chamber in fluid communication with the optic fluid chamber,
wherein in each of the first and second cross sections there is only a single lumen, the single lumen being the haptic fluid chamber,
wherein the haptic fluid chamber has the same configuration, in cross section, in the first section and the second section,
wherein the haptic is adapted to deform in response to forces on the haptic due to ciliary muscle movement to thereby move a fluid between the haptic fluid chamber and the optic fluid chamber to change an optical parameter of the accommodating intraocular lens.
2. The accommodating intraocular lens of claim 1 wherein the haptic is adapted to be more sensitive to capsular bag forces in the radial direction than it is to capsular bag forces in the anterior-to-posterior direction.
3. The accommodating intraocular lens of claim 1 wherein the haptic is adapted to deform more in response to forces in the radial direction that it is to forces in the anterior-to-posterior direction.
4. The accommodating intraocular lens of claim 1 wherein the haptic is adapted such that a greater volume of fluid moves between the peripheral fluid chamber and the optic fluid chamber in response to forces on the haptic in the radial direction that in response to forces on the haptic in the anterior-to-posterior direction.
5. The accommodating intraocular lens of claim 1 wherein the first inner wall radial thickness is about three times the thickness of the outer wall radial thickness along a midline of the haptic.
6. The accommodating intraocular lens of claim 1 , wherein in the first cross section the haptic fluid chamber has a radially inner surface that is more linear than a haptic fluid chamber radially outer surface.
7. The accommodating intraocular lens of claim 1 , wherein the haptic has a first portion that includes the first cross section with the first radially innermost wall thickness, and wherein the first radially innermost wall thickness subtends an angle of about 40 degrees around the optic portion.