Fuch's dystrophy is an abnormality of the cells that line the inner layer of the cornea. These cells are known as endothelial cells. They are very important to the overall health of the cornea. These cells are responsible for keeping the cornea in a relatively dehydrated state. They pump excess fluid from the cornea. If the cornea becomes swollen with fluid, it becomes hazy, cloudy and painful. People with Fuch's dystrophy not only have a decreased number of endothelial cells, the cells that they do have are abnormal and are functioning sub optimally.