T1 FLAIR

[AndrewBworth]

Another advantage of T1-FLAIR is that it can be used with methods that lead to a variable TR. For example, when the initiation of the pulse sequence is dependent on a patient's respiration - regular T1 sequences cannot be used because the contrast is dependent on the TR. However in T1-FLAIR, we are dependent on TR simply exceeding some minimum value. In these protocols - it is probably ideal if the time between pulse sequence initiation and echo acquisition is as short as possible - so T1 weighted GRE sequences may be preferred, but T1 FLAIRS are a possibility. Also, T1-FLAIR methods appear to be more compatible with BLADE/PROPELLER sequences because they can achieve a higher turbo factor than regular T1 sequences (why this is, the lightbulb has not yet turned on). The turbo factor on T1-FLAIR BLADE at my current hospital is 19, whereas the turbo factor on T1 sequences is usually 3. I believe for BLADE to be used with its motion correction post processing algorithm - the turbo factor/blade width must be higher, (I have read 29, but I don't know my systems specifics) - this could be accomplished with a GRAPPA dependent scheme.