[Variation of intraocular pressure by non-contact tonometry and cardiac pulse wave].
We performed successive IOP measurements with a noncontact tonometer (NCT) in twelve eyes of six normal volunteers to analyze the relationship between the variation of IOP and the cardiac cycle. For this study, we devised a special apparatus composed of an photoelectric plethysmograph, an electric cardiograph and a NCT. With this apparatus, non-contact tonometry was permitted only at the peak or trough of the cardiac pulse wave. At the peak or trough of the cardiac pulse wave, IOP showed a variation of 0.8 +/- 0.4 mmHg (mean +/- s.d.) which was thought to be caused mainly by respiration. Between the peak and trough of the cardiac pulse wave, we found a maximum difference in IOP of 3.8 +/- 1.0 mmHg and a mean difference of 1.9 +/- 0.8 mmHg, which seemed to be attributable to the cardiac cycle.
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Nanba
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Nakayama
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Iwata
D000328:Adult; D006801:Humans; D007429:Intraocular Pressure; D008297:Male; D008875:Middle Aged; D011674:Pulse; D012119:Respiration; D014065:Tonometry, Ocular / Q000295:instrumentation / Q000379:methods