I have not heard about a strong connection between cataracts and
insulinoma.  The development of cataracts with the antithesis of
insulinoma, i.e., diabetes mellitus, is well known.  The mechanism behind
this is the elevation of glucose in the eye, which slowly diffuses into
the lens.  For this reason, the lens takes on water, and the cells of the
lens balloon and disrupt, resulting in a cataract.
 
Not many ferrets actually have cataract removal surgery, as these are
poorly sighted creatures, and the possibility of retinal disease may make
cataract surgery an exercise in futility.  A visit with a veterinary
opthalmologist however, may do well to outline your options in this case.
 
With kindest regards,
Bruce H. Williams, DVM, DACVP
 
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[Posted in FML issue 3438]