tonography


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tonography

 [to-nog´rah-fe]
the recording of changes in intraocular pressure due to sustained pressure on the eyeball.
carotid compression tonography a test for occlusion of the carotid artery by measuring ocular pressure and pulse before, during, and after the proximal portion of the carotid artery is compressed by the fingers.
Miller-Keane Encyclopedia and Dictionary of Medicine, Nursing, and Allied Health, Seventh Edition. © 2003 by Saunders, an imprint of Elsevier, Inc. All rights reserved.

to·nog·ra·phy

(tō-nog'ră-fē),
Continuous measurement of intraocular pressure by means of a recording tonometer to determine the facility of aqueous outflow.
Farlex Partner Medical Dictionary © Farlex 2012

to·nog·ra·phy

(tō-nog'ră-fē)
Continuous measurement of intraocular pressure by means of a recording tonometer, to determine the facility of aqueous outflow.
Medical Dictionary for the Health Professions and Nursing © Farlex 2012

tonography 

Technique for measuring the facility of outflow of aqueous humour from the eye under the continuous pressure exerted by the weight of a tonometer over a given period of time. The instrument usually employed for tonography is an electronically recording Schiötz tonometer. In this technique, the pressure is continuously recorded over a four-minute period and the outflow is deduced by utilizing a specifically designed diagram, called a nomogram (which is a graphical representation of one, or more, mathematical relationships whereby the desired value may be found without calculation by placing a straight edge across the diagram). The results of tonography can indicate the presence of established glaucoma, although the technique is not very reliable for borderline cases.
Millodot: Dictionary of Optometry and Visual Science, 7th edition. © 2009 Butterworth-Heinemann