What is PSIR MRI?

What is PSIR MRI?

Phase-sensitive inversion-recovery (PSIR) is a technique commonly used in cardiac MRI to enhance the contrast between normal and infarcted heart tissue while nulling signals from blood and fat. In PSIR, two datasets are acquired, a conventional image and a reference phase dataset.

What is true inversion recovery?

Inversion-recovery is a magnetization preparation technique followed by an imaging sequence of the spin echo type in its « standard » version . The sequence starts with a 180° RF inversion wave which flips longitudinal magnetization Mz in the opposite direction (negative).

What is turbo factor in MRI?

After each echo, the phase-encoding is cancelled and a different phase-encoding is applied to the following echo. The number of echoes received in the same repetition (during TR time) is called the Turbo Factor or Echo Train Length (ETL).

What is T2 flair signal?

T2/FLAIR. T2/FLAIR images show the total amount of scar from MS from its onset. The pictures show both old and new inflammation. T2/FLAIR lesions can directly account for some symptoms. For example, a brainstem lesion can cause room spinning sensations and balance problems.

Is Flair T1 or T2?

FLAIR MRI is a heavily T2-weighted technique that dampens ventricular CSF signal. This causes the highest signals on the sequence are from certain brain parenchymal abnormalities, such as MS lesions, while the CSF appears black.

What is TSE sequence?

The FSE/TSE pulse sequence (illustrated above) superficially resembles a conventional spin-echo (CSE) sequence in that it uses a series of 180º-refocusing pulses after a single 90º-pulse to generate a train of echoes.

What is FSE and Tse?

Fast or turbo spin echo (FSE/TSE) is an adaptation of conventional spin-echo (SE) acquisition technique designed to reduce imaging time. It has largely supplanted the original spin-echo technique due to vastly improved imaging speed.

What is the difference between T1 FLAIR and T2 FLAIR?

The Flair sequence is similar to a T2-weighted image except that the TE and TR times are very long. By doing so, abnormalities remain bright but normal CSF fluid is attenuated and made dark….

	TR (msec)	TE (msec)
T1-Weighted (short TR and TE)	500	14
T2-Weighted (long TR and TE)	4000	90
Flair (very long TR and TE	9000	114