It is an information to state that any action,process or function has begun.It is the US abbreviation for the name of the Canadian Province of Ontario.It is a preposition mean â¦ ing that one object is in contact with, and usually above, another object.
Sparing the nucleus: Cortical cataracts are in a layer of the lens outside of the nucleus which is the center of the lens. They are sometimes congenital. Depending upon the density they may disturb the vision but sometimes are thin enough not to be a problem.
A cataract is defined as any opacification of the eye's crystalline lens, and any of these changes that then lead to a degradation in the optical quality of the lens can cause visual symptoms.