National Glaucoma Research - Current Award

	Jonathan Vande Geest, Ph.D. University of Arizona Tucson, AZ Title: Microstructural And Biomechanical Properties Of Human Sclera Non-Technical Title: Organization And Properties Of The Human Sclera And Its Relation To Glaucoma Acknowledgements: Recipient of the Thomas R. Lee award for National Glaucoma Research Duration: April 1, 2009 - March 31, 2011 Award Type: Standard Award Amount: $100,000
Summary: This research is aimed at identifying whether changes in peripapillary human scleral microstructure and mechanical properties occur within human donor eyes of varying ages, races, and in the presence or absence of glaucoma. Such information will be important in quantifying the biomechanical environment of the optic nerve head. These studies may also eventually lead to improved diagnostic tools for glaucoma.

Details:

Recent research has suggested that the sclera (the white part of your eye) plays an important role in determining the forces acting on the nerves that carry the optical signal from your eye to your brain. These forces are thought to be critical in the development of glaucoma. We believe that changes in the organization of the proteins that make up the sclera may predispose certain ethnic populations to glaucoma. This hypothesis is strengthened by the fact that certain ethnic populations are at higher risk for developing glaucoma, even though they have normal values of intraocular pressure.

Our research goal is unique in that it seeks to understand the relationship between the structure and mechanical function of the sclera. That is, an alteration in the structure of the sclera may lead to drastic changes in its mechanical behavior -- which will itself predispose a patient to abnormal loads in critical regions of the eye. Furthermore, should such alterations be detectable noninvasively, a unique opportunity will exist to better identify those at high risk for glaucoma earlier in the disease progression.

In our research we:

1) use sophisticated experiments to characterize how the mechanical properties of the sclera vary with age, race, and glaucoma; and

2) use sophisticated imaging techniques to quantify how such changes occur.

Our team is especially excited about utilizing state of the art techniques in biomechanics and bioimaging to develop new and innovative diagnostic tools for glaucoma.

Publications:

Mortazavi AM, Simon BR, Stamer WD, Vande Geest JP. (2009) Drained secant modulus for human and porcine peripapillary sclera using unconfined compression testing. Exp Eye Res. 2009 Dec;89(6):892-7.  

(This manuscript details the compressive mechanical properties of human and porcine scleral specimens. Particular attention was placed to the equilibrium compressive moduli of these tissues. Future investigations will also utilize resulting datasets for visco/poro elastic quantification. )