Age and sex dependency of blood flow velocity in the internal carotid artery.

BACKGROUND AND PURPOSE Colour-coded duplex sonography is a handy, cost-effective method of screening for stroke-endangered subjects through reliable measurement of blood flow velocity within the internal carotid artery (ICA). The purpose of this investigation was to analyze the effect of age and sex on blood flow velocity and side-to-side differences in the ICAs. MATERIAL AND METHODS Three hundred forty-three healthy volunteers (215 women and 128 men) were divided into 3 age groups: group I 60 years. Blood flow velocities in the ICA were examined with a Toshiba scanner Aplio SSA 770A, endowed with a linear 7.5 MHz probe. RESULTS Blood flow velocities in the ICA (mean +/- SD, cm/s) were as follows. In men (group I/group II/group III): peak systolic (PSV) - 64.0 +/- 18.2/58.6 +/- 14.4/60.3 +/- 18.2, mean (MV) - 36.0 +/- 8.3/34.1 +/- 8.5/33.8 +/- 9.3, end diastolic (EDV) - 24.7 +/- 6.2/22.9 +/- 6.8/20.1 +/- 5.5. In women (group I/group II/group III): PSV - 77.2 +/- 16.9/66.5 +/- 20.4/52.5 +/- 16.7, MV - 45.4 +/- 9.5/42.2 +/- 12.2/31.0 +/- 10.3, EDV - 30.8 +/- 7.3/28.1 +/- 9.1/18.7 +/- 6.9. Blood flow velocities were stable up to the age of 40-45 years and during this age span were significantly higher in women than in men. After that age, blood flow velocities continued to decrease in both ICAs in women whereas in men this decrease was less steep and pertained mainly to the right ICA. CONCLUSION The pattern of blood flow in the ICA changes with age in a different way in men than in women.