CORNEAL STAINING


If only the superficial epithelial 
cells are damaged, the 
fluorescein staining will be 
limited to the area of damage.  
If the full thickness of the 
epithelium is damaged 
fluorescein will seep into the 
stroma giving a larger area of 
staining then the defect.  The 
borders will not be distinct 
since the fluorescein is slowly 
diffusing through the stroma.