On the printout, there is a space for the technician to note the size of the pupil during the test. Perhaps 14 to 16 mm Hg could be considered to be ideal. Local anesthetic drops are administered to the eye to minimize discomfort. Next, a lens illuminated with a blue light and having a known curvature pushes gently on the eye at a known rate as a technician or doctor visually determine the degree of deflection of the cornea to the lens. Thus, cupping is something that must be closely monitored and measured in glaucomatous eyes.
Cupping is expressed in terms of a cup to disc ratio.
Glaucoma with normal IOP's. Generally, both eyes will be affected, but not necessarily equally. POAG is typically characterized by elevated IOP which is associated with cupping and atrophy of the optic nerve head at the back of the eye. Loss of visual field is associated with deformation of the optic nerve head. Eye examination by a special prism or contact lens containing a mirror.