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Tonometry

How It Is Done continued...

You will rest your chin on a padded support and stare straight into the microscope (slit lamp). Your doctor sits in front of you and shines a bright light into your eye. Your doctor gently touches the tonometer probe to your eye. Your doctor checks the tension dial on the tonometer that measures the IOP of your eye.

Do not rub your eyes for 30 minutes until the numbing medicine has worn off.

Electronic indentation method

Electronic tonometry can be done by a technician, an optometrist, an ophthalmologist, or a family medicine doctor. Your doctor will use eyedrops to numb the surface of your eyes so that you will not feel the tonometer during the test.

You will stare straight ahead, or sometimes look down. Your doctor gently touches the tonometer probe to your eye. Several readings will be taken on each eye. You will hear a clicking sound each time a reading is obtained. After enough accurate readings have been obtained, a beep will sound, and the averaged IOP measurement will appear on the instrument's display panel.

Do not rub your eyes for 30 minutes until the numbing medicine has worn off.

Noncontact (or air-puff) method

This type of tonometry is done by an ophthalmologist or an optometrist. You do not need drops to numb your eye for this method.

You will rest your chin on a padded support and stare straight into the machine. A brief puff of air is blown at your eye. You will hear the puffing sound and feel a coolness or mild pressure on your eye. The tonometer records the intraocular pressure (IOP) from the change in the light reflected off the cornea as it is indented by the air puff. The test may be done several times for each eye.

How It Feels

Tonometry should not cause any eye pain. Your doctor will use eyedrops to numb the surface of your eyes so that you will not feel the tonometer during the test. You may have a scratchy feeling on your cornea. This usually goes away in 24 hours.

Some people become anxious when the tonometer needs to be touched to the eye. In air-puff tonometry, only a puff of air touches the eye.

WebMD Medical Reference from Healthwise

Last Updated: February 28, 2012
This information is not intended to replace the advice of a doctor. Healthwise disclaims any liability for the decisions you make based on this information.

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