What type of weightings can be obtained with FSE?įSE may be lower in quality, but the advantage is:īecause of the repeated 180 pulses which don't allow for full fat relaxation. If we take a close look at a pulse sequence diagram, we can see that during the excitation pulse, we need to create resonance that affects only a slice of data. What can be used to correct for the brightness of fat on all weightings using FSE? Images created with FSE are similar to those made with SE, except _ remains bright on all weighting. Using an effective TE will reorder phase steps so that a _ _ phase steps are centered around the chosen TE to get the best info T2 FSE requires _ (long/short) ETL, up to _ on some scans Using long ETLs on FSE T1 would result in image _ The number of lines of data (k-space) filled by a FSE is the same at the _Ī FSE for T1 image would use a maximum of _ ETL The number of 180 pulses done after the 90 in FSE is known as the _ _ _ In this sequence, several 180 refocusing radio-frequency pulses are delivered during each echo time (TR) interval, and the phase-encoding gradient is briefly switched on between echoes. Many 180 pulses after the initial 90 pulse. Fast spin echo (FAISE or FSE, ref 65bis), also called turbo spin echo (TSE) is an MRI sequence that results in fast scan times. The main feature of the FSE pulse sequence is. Rapid acquisition relaxation enhanced (RARE) Two image sets for one scan time - efficiency Long TR, one short TE (for PD) and one long TE (for T2) How many lines of k-space are filled with a multi-echo spin echo?Ī multi-echo spin echo develops which two types of images? What is the sequence for multi-echo spin echo? The use of the 180 RF pulse to rephase the NMV for signal creation The main thing that makes spin echo pulse sequence unique from other sequences is: Information on the QUANTITY of tissue in an area (for example, how much edema is in an area) Versatility (planes, image weightings, etc)įor good demonstration of pathology on T1 SE, you need _ The three advantages of the SE sequence are: Why is the FE often called the readout gradient in the SE sequence?īecause it is on during the echo, which gives us our signal. The bottom three lines of a PSD are the gradient functions - SS, PE, and FE. The first line of a pulse sequence diagram (PSD) is always _ The SE sequence fills how many lines of K-space? Which type of weighting(s) are possible with SE? Which pulse sequence was the first one developed and is still considered the "gold standard" for quality against which newer ones are compared - however it is slower. STIR and FLAIR sequences are types of _ pulse sequences. T 1 T 1, T 2 and proton density (PD)Proton density ( Inversion-recovery (IR) Inversion recovery (IR) pulse sequence diagram. What are the two main types of spin echo pulse sequences?
#Spin echo sequence diagram series#
to correct magnetic field inhomogeneities.Ī series of RF and gradient applications that has carefully controlled durations and timings. to rephase/refocus the spins in the transverse planeĢ. What are the two purposes of the 180 degree pulse in the spin echo sequence?ġ. In the spin echo pulse sequence, when is the echo collected? Click here to study/print these flashcards.Ĭreate your own flash cards! Sign up here.