There is no normal intraocular pressure sugar, it should be normal intraocular pressure. The eye is a sealed cavity containing contents, and the pressure of the contents of the eye acting on the wall of the eye is known as normal intraocular pressure, or IOP for short. Under normal physiological conditions, intraocular pressure is not constant and may vary slightly. In a normal person, the difference between day and night variations in intraocular pressure should be between 2 and 4 mmHg. The current normal range of IOP is 10 to 21 mm Hg. It is usually measured with a Schiφtz tonometer, with a mean value of 15 to 16 mm Hg and 21 mm Hg as the upper limit of normal. 22 to 23 mm Hg is the suspicious range and should be examined further, usually with repeated and accurate measurements. If it is greater than 24 mm Hg, it needs to be considered pathologic in conjunction with other indicators. High intraocular pressure may be due to glaucoma, or hypertensive eye disease. Usually, if the diagnosis of glaucoma is confirmed, a lot of other indicators need to be examined, such as 24-hour intraocular pressure, visual field examination, fundus examination, anterior chamber keratoscopy and corneal central thickness examination to make a comprehensive judgment. If glaucoma has been diagnosed, it is necessary to lower the intraocular pressure in time to treat it, otherwise it will eventually lead to irreversible damage to the optic nerve, and there will be loss of vision as well as visual field defects.