  The eye lens is the most characteristic example of mammalian tissues
exhibiting complex colloidal behaviour. In this paper we briefly describe how
dynamics in colloidal suspensions can help addressing selected aspects of lens
cataract which is ultimately related to the protein self-assembly under
pathological conditions. Results from dynamic light scattering of eye lens
homogenates over a wide protein concentration were analyzed and the various
relaxation modes were identified in terms of collective and self-diffusion
processes. Using this information as an input, the complex relaxation pattern
of the intact lens nucleus was rationalized. The model of cold cataract - a
phase separation effect of the lens cytoplasm with cooling - was used to
simulate lens cataract at in vitro conditions in an effort to determine the
parameters of the correlation functions that can be used as reliable indicators
of the cataract onset. The applicability of dynamic light scattering as a
non-invasive, early-diagnostic tool for ocular diseases is also demonstrated in
the light of the findings of the present paper.
