During routine eye exams, a tonometer is used to measure intraocular pressure,
or IOP. Eye
is numbed with eye drops, and a small probe gently rests against the eye's surface. Other tonometers send a puff of air onto the eye's surface.
An unusually high IOP reading shows a problem with the amount of fluid (aqueous humor) in the eye i.e. either the eye is producing too much fluid, or it is not draining properly.
Normally, IOP should be below 21 mmHg (millimeters of mercury) based on how much force is exerted within a certain defined area.
If the IOP is higher than 30 mmHg, the risk of vision loss from glaucoma is 40 times greater than someone with intraocular pressure of 15 mmHg or lower.
Other methods of monitoring the glaucoma involves the use of sophisticated imaging technology which are mentioned as follows:-
a. scanning laser polarimetry (SLP),
b. optical coherence tomography (OCT) and
c. confocal scanning laser ophthalmoscopy