The Hubble Telescope of the Eye

The quest for truly non-invasive ocular biomechanical measurements

By Mark Hillen

March 2107

When it comes to rheology – the branch of physics that deals with the deformation and flow of matter, especially the non-Newtonian flow of liquids and the plastic flow of solids – the eye is one hell of a playground. Some structures are somewhat rigid (like the sclera) and others barely at all (the aqueous humor). It’s a pressurized system, drainage issues can cause huge problems, there’s a multitude of muscles that can change not only the direction of the eye at any given moment but also the shape of the tissues inside it. Aging progressively stiffens the principal component of the eye’s focusing system: the lens, and this is all before we get to refractive surgery like astigmatic keratotomy, PRK, LASIK, and SMILE weakening the cornea, let alone any disease states.