Pulsed Doppler ultrasound for measuring blood flow velocity in the human ophthalmic circulation

This study was performed in order to develop a method for studying blood flow in the ophthalmic circulation. Using a pulsed doppler system utilizing an ultrasonic frequency of 10 MHz, blood flow velocities have been measured in the ophthalmic artery and in the arteries behind the eyeball (lateral posterior ciliary arteries) in 40 normal subjects. The mean of the peak systolic velocities were 34 +/- 6 cm/s in the ophthalmic artery, and 14 +/- 3 cm/s in the lateral posterior ciliary arteries. We conclude that blood flow velocities can be measured in defined vessel areas in the orbit.