Method for measuring and imaging fluid flow

摘要

A time-of-flight magnetic resonance pulse sequence is used to detect arterial flow in an image of a slice of tissue. By timing the pulse sequence with the cardiac cycle and by holding the interpulse interval TI within time limits which ensure enhancement without significant change in flow velocity, arterial flow can be imaged. By triggering the pulse sequence from the QRS complex representative of the beginning of a body's cardiac cycle and delaying both excitation and detection pulses in the sequence by a time TA to ensure the pulses occur while flow is slow, MR signal data is generated which results in an image showing enhancement in the areas of arterial flow. In an extension of the foregoing, a second set of MR signal data is generated by adjusting the acquisition delay TA such that the excitation and detection pulses of a second sequence occur while arterial flow is fast. In the image formed from this second set of data, the increased arterial flow velocity decreases the enhanced image of the arteries. The images generated from the MR signals of the first and second sequences may be subtracted in order to give a single high contrast image showing only arterial flow.