Description:
Princeton University Invention #
05-2211
Presbyopia is a
natural age-related process that affects everyone from the age of 45 on,
regardless of whether or not they have always had normal vision or have suffered
from myopia, hyperopia or astigmatism. Presbyopia is the increasing inability to
maintain near objects in focus. People with presbyopia have to hold reading
materials at arms¿ length to be able to focus on the image. Currently
there is no surgical correction for presbyopia available that directly restores
the accommodative ability of the native crystalline lens.
Researchers in
the Department of Mechanical and Aerospace Engineering, Princeton University
have developed a device and procedure with the potential for correcting
presbyopia. This invention will allow for minimally invasive laser surgery of
the lens of the eye to correct for presbyopia. The invention uses a femtosecond
laser, together with proprietary software to precisely remove, by
photablation, prescribed portions of the eye lens, with the added possibility of
replacing the removed parts of the lens with a specially developed polymer with
suitable biomechanical and refractive properties. The use of femtosecond lasers
provide high intensity light at very low energy levels so that the ablation
proceeds very precisely, with negligible heating and collateral
trauma.
Although the
mechanisms of human accommodation remain controversial, most evidence supports
the Helmholtz model¹ of accommodation where contraction of the ciliary muscle
releases zonal tension on the lens capsule. This allows the normal elastic
properties of the lens to cause the anterior radius of curvature to decrease.
Since volumetric and morphological conditions exacerbate presbyopia by changing
biomechanical properties of the lens as well as the efficacy of the zonular
mechanism, it is possible that decreasing lens volume would help to restore a
normal accommodative amplitude. The removal of lens material using photoablation
with femtosecond lasers would give a methodology for altering the lens optics
and mechanics to restore accommodation.
Preliminary
in vitro data is very encouraging and further work is ongoing.
Selected
Publications:
¹Helmholtz, H.,
¿Treatise on Physiologic Optics¿, Translated from the 3rd
German
Southall. J.P.,
ed. New York: Dover Publications (1962).
Glasser A. and
Kaufman P.L., ¿The Mechanism of Accommodation in Primates¿, Ophthalmology, 106:
863-872 (1999).
Brown N., ¿The
Shape of the Len Equator¿, Experimental Eye Research, 19:571-576
(1974).
Princeton
University is currently seeking industrial collaborators to assist in the
development and commercialization of this invention. Patent protection is
pending.
For more information on Princeton
University Invention # 05-2211 please contact:
Laurie Tzodikov
Office of Technology Licensing and Intellectual Property
Princeton University
4 New South Building
Princeton, NJ 08544-0036
(609) 258-7256
(609) 258-1159 fax
tzodikov@princeton.edu