Increasing T1 Contrast in MRI with Quasi-continuous Low-level Radio Frequency Energy
Publication Date: 2003-May-08
The IP.com Prior Art Database
This invention increases the T1 contrast in spin-echo imaging, with very little reduction in the total number of slices that can be acquired. Throughout the multiple-slice imaging experiment, the whole object is quasi-continuously irradiated with low-level RF energy at or near the spin resonance frequency. The effect of the saturation is to change the steady state magnetization of the different T1 components, such that the steady state longitudinal magnetization of the long T1 components is reduced with respect to that of the short T1 components. Simulations suggest that a saturation pulse with a flip angle of between 5 and 15 degrees, applied every 25ms, in a 20 slice T1 weighted spin-echo imaging acquisition, should increase the contrast between white and gray matter in the brain by at least 50%. The signal difference to noise ratio should increase about 15%. The technique could also be applied for other T1 weighted imaging sequences such as gradient-echo.