The measurement of eye pressure is in millimetres of mercury (mm Hg). The typical range for eye pressure is 12-22 mm Hg, while pressures more than 22 mm Hg are considered abnormal. Glaucoma is not caused by high eye pressure alone. It is, nonetheless, a considerable risk factor. Individuals with high eye pressure should get comprehensive eye exams by an eye care specialist on a regular basis to screen for signs of glaucoma.