Amethocaine and Intraocular Pressure

Abstract

Intraocular pressure (IOP) is usually measured by methods necessitating the use of local anesthetic drugs. The effect of these agents on IOP is the subject of this study. We have measured IOP with a noncontact tonometer before and after application of a local anesthetic solution to one eye, the other eye serving as a control. A reduction of pressure occurred in the treated eye, but it is concluded that for practical purposes, local anesthesia does not falsify the results of IOP measurements.

On repeated corneal applanation with the Goldmann and two non‐contact tonometers

“…AlMubrad and Ogbuehi 16 reported a 2 mmHg (or greater) reduction, in the average IOP measured with a non‐contact tonometer after repeated applanation with the Goldmann tonometer, in 43 and 46 per cent of the same subject sample on two separate measurement sessions. The process responsible for inducing this ‘ocular massage effect’, which was first described by Stocker, 9 has not been elucidated but it does appear that topical anaesthesia may play a significant role in its genesis 30–32 . In the study by Ogbuehi and AlMubrad, 32 the IOP measured with a non‐contact tonometer decreased by between 0.7 mmHg and 1.0 mmHg, depending on the anaesthetic used (0.4% oxybuprocaine or 0.5% proparacaine) and on the post‐instillation time at which the IOP was remeasured (two and five minutes).…”

“…The process responsible for inducing this 'ocular massage effect', which was first described by Stocker,9 has not been elucidated but it does appear that topical anaesthesia may play a significant role in its genesis. [30][31][32] In the study by Ogbuehi and AlMubrad, 32 the IOP measured with a non-contact tonometer decreased by between 0.7 mmHg and 1.0 mmHg, depending on the anaesthetic used (0.4% oxybuprocaine or 0.5% proparacaine) and on the post-instillation time at which the IOP was remeasured (two and five minutes). As the reduction in non-contact IOP in this study caused by applanation with the Goldmann tonometer was between 0.6 mmHg and 1.2 mmHg (depending on which non-contact tonometer was employed) and as the interval between Goldmann applanation and non-contact tonometry assessments was between two and five minutes, it is probable that a significant proportion of the ocular massage effect is explained by the effect of topical anaesthesia.…”

Effect of Pilocarpine on Intraocular Pressure in Normal Humans

“…During this examination, IOP is measured in all subjects aged 40 years and above. An American Optical noncontact tonometer is used, as previously described [1). Those subjects with an IOP above 15 mm Hg were recalled for an extensive ophthalmological examination.…”

Correlation of Headache Complaints With Some Physiological Parameters in a Healthy Population

“…Intra-ocular pressure was measured by an American Optical non-contact tonometer, as previously described. 1 Values higher than 25 mmHg were considered abnormal. Blood pressure was taken in the supine position, using an automatic Kenz-45 instrument.…”