Reply to comment by Ronald A. Schachar on the publication “Stiffness gradient in the crystalline lens” by H.A. Weeber et al.

Excerpt

In our study we measured the stiffness gradient of human lenses. The lenses had been stored frozen and were thawed prior to testing. In his first comment, Dr. Schachar expresses his concern about the influence of freezing and thawing on the stiffness gradient of the lens material. He refers to three studies that would indicate that the shear moduli of nucleus and cortex could be affected differently by freezing and thawing and thus affect the measured gradient stiffness of the lenses. Interestingly, the first two studies that are mentioned concern the behavior of cold cataracts. We believe that the most relevant characteristic of cold cataract is that it is a reversible process [1‐4], and this is true for both nucleus and cortex. Cold cataract can be produced without disruption of cell size, shape, structure, or cellular organization [3]. …