OCULAR PULSE AMPLITUDE DURING MANIPULATION OF SYSTEMIC PERFUSION PARAMETERS

Background The mechanism for the control of choroidal perfusion is unc lear. The present study was designed to investigate for the effect of standardized alteration of systemic perfusion parameters on choroidal hemodynamics in healthy volunteers. Methods Intraocular pressure (IOP; German abreviation: IOD), Ocular Pulse Amplitude (OPA), systemic bloo d pressure, and pulse rate were measured, and ocular perfusion pressur e was calculated in 14 otherwise non-smoking, healthy volunteers prior to and following exercise and smoking. Results Exercise significantly (sig., p < 0.05) increased pulse rate, systolic blood pressure and oc ular perfusion pressure, while it sig. (p < 0.05) reduced IOP and dias tolic blood pressure. However OPA was not sig. (p>0.1) affected by cha nges in these parameters. Smoking sig. (p<0.05) increased systolic blo od pressure, diastolic blood pressure, pulse rate, and ocular perfusio n pressure but did not sig. (p > 0.09) alter OPA. Conclusion Despite a ffecting ocular and systemic perfusion parameters, exercise and smokin g did not alter OPA, suggesting functional isolation i.e. autoregulati on of the choroidal and/or ophthalmic artery circulation.