As with any medical treatment, eye exams need to be performed professionally and with the least amount of discomfort. If a patient is interested in knowing how a test is performed, what it involves and what type of medical equipment will be used, he or she can speak with the doctor to get a better understanding. All of the questions patients have are relevant, and the more comfortable a patient feels, the easier it will be for the doctor to perform the procedure.
An eye pressure test is a procedure performed by an optometrist. An optometrist provides primary care such as vision testing, small correction treatments, eye exams, lens prescriptions and medication prescriptions for less invasive eye diseases such as allergies. Optometrists are trained and educated to perform different procedures using different equipment and methods. An eye pressure test is called tonometry. This test is used to diagnose glaucoma and other eye diseases. Since glaucoma has no symptoms, it is very hard to detect.
The first step in a tonometry test is usually eye drops. Eye drops help to numb the eye surface and this numbing helps the doctor get more accurate readings. Also, it helps the patient stay calm and keep his eyes still. After applying the numbing drops, a patient is ready for the procedure. Instruments used during the test measure pressure on the cornea and how it reacts. A simple screening test is the most common, and it is called air-puff. But these results are used and checked with additional tests.
There are three possible ways to measure eye pressure.
Applanation tonometry measures how much pressure is necessary to flatten the cornea. It is a simple test done after an air-puff test. To get results the doctors uses a slit lamp microscope.
Electronic indentation uses a pen-like tool to press on the cornea. This tool is gently pressed directly and can cause discomfort for the patient. It is used to check high IOP or in ocular pressure.
Pneumotonometry, also known as non-contact tonometry, is the aforementioned air-puff method. There is no direct tool contact with the cornea. Numbing eye drops are not needed since this is a noninvasive method. Again, how much pressure needed to flatten the cornea is measured. This method is used together with others since it can give results for IOP and it can show if any additional check-ups are necessary.
The tonometry result is the first indicator of glaucoma. If the reading is high it means there is glaucoma present. The desired result is a reading between 10-21 MmHG. A reading below or above indicates problems. It could mean glaucoma, eye inflammation, corneal injury or hyphema. The result of the eye pressure test will give more details and a better picture future steps that should be taken.