[A design of two-dimensional time-of-flight using the multi echo collection]

In general, gradient echo (GRE) is used for the echo acquisition of two-dimensional time-of-flight (2D-TOF). It takes time to the image acquisition by 2D-TOF. Then, we designed the use of GRE-echo planar imaging (EPI) to the echo collections of 2D-TOF. We compared two pulse sequences using the following: contrast, signal to noise ratio, the distortions, and magnetic resonance angiography (MRA) images. The signal intensity ratio between blood vessel and fat was superior to the GRE-EPI. Signal to noise ratio of GRE-EPI was inferior to GRE. When the number of collection echoes of GRE-EPI is carried out by four, there was no distortion. The contrast of the blood vessel has improved when GRE-EPI was used. Image acquisition time improved to about 23 percent earlier. The blood vessel of the parent trunk was able to be described in the image of the lower limbs blood vessel. However, the description of the peripheral vessel was dominant 2D-TOF that used GRE. In clinical, the description of the peripheral vessel may not be important. With such a case, this method is effective. Moreover, shortening the image acquisition time brings a reduction to the load of the patient.