Ocular Biomechanics

Dr. Alan Argento, Dr. Sayoko Moroi and Dr. Guan (Gary) Xu

This is joint research between Dr. Alan Argento, Dr. Sayoko Moroi and Dr. Guan Xu. We are working on projects focused on the biomechanics and multispectral photoacoustic imaging of the anterior chamber.

One representative study in our lab is to resolve the anatomy and compute biomechanical behaviors of tissue components, specifically the aqueous veins and surrounding perilimbal sclera. The work involves varying intraocular pressure to induce deformation of the tissue components. The deformation of each component is quantified from the images, tracked and used to determine 3D strains by finite element methods. These quantitative measurements assist in understanding the biomechanical characteristics of the tissue components, their interactions, and roles in disease, which is glaucoma in this case.

Funding Support: The Glaucoma Foundation, National Science Foundation CMMI 1760291, Kellogg Eye Center startup fund.


Team

Dr. Amanda Bicket, Assistant Professor

Dr. Wonsuk Kim, Associate Research Scientist

Linyu Ni, PhD Candidate

Erik Krawczyk, Research Assistant

Alexus Warchock, Research Assistant

PAM-FEA in human eye. (a) Full circumferential PAM image of a human eye. Aqueous veins (A) were rendered in green and the surrounding sclera (S) is in gray. (b-c) and (d-e) are the magnified regions in (a) with tissue components shown separately. (f) PAM image of a small tissue region with tracked spatial features of aqueous veins (red) and surrounding sclera (blue). Scalebar: 250 µm (g) 3D finite element model of the aqueous vein. (h-i) Strains of the aqueous veins and the surrounding sclera (normalized to the scleral thickness and the eye’s diameter) in the directions across the vein (x) and normal to the eye surface (z). (j) Cross-section of the aqueous vein at 2.5 (IOP 1) and 14 (IOP 2) mmHg.

The video below shows the evolution of deformation and strains in a whole intact human globe during increase in intraocular pressure. The video is a result of photoacoustic imaging and tracking of points on an aqueous vein followed by 3D finite element computation of the strains. Through the thickness, in-plane and longitudinal vein strains are shown along with the deformation of a cross-section. The change in the shape of the vein and cross-section influences the outflow of the aqueous.