The drainage angle is the point in the eye where the colored part of the eye (iris) and the white covering over the eye (sclera) meet. This is where fluid within the inner eye (which is different from tears that lubricate the eye's outer surface) drains.
Blockage of this angle can lead to increased pressure in the eye. The increased pressure can damage the optic nerve and cause glaucoma.
Medical Review:Adam Husney MD - Family Medicine & Christopher J. Rudnisky MD, MPH, FRCSC - Ophthalmology