A method of estimating mean central retinal artery pressure (MCRAP) by using a microprocessor controlled tonometer (10), the method comprisingusing the tonometer (10) to determine a mean intraocular pressure [MIOP] including a diastolic value and a systolic value having an ocular pulse amplitude [OPA]using the microprocessor (20) to calculate a ratio between OPA and MIOPusing the microprocessor (20) to derive a multiplier from the ratio andusing the microprocessor (20) to multiply MIOP by the derived multiplier to produce an estimate ofmean central artery pressure [MCRAP].