Maximum linear relationship between contrast agent concentration and signal intensity on T1 weighted images using inversion recovery and saturation recovery sequences (Centre out Phase-Encoding acquisition) in MRI

Purpose: To investigate the effect of variation of inversion time (TI) and saturation time (TS) on the maximum relationship between contrast agent concentration and signal intensity (SI) on TurboFLASH T1-weighted images in MRI, using inversion recovery (IR) and saturation recovery (SR) sequences (Centre out Phase-Encoding acquisition .( Materials and methods: A phantom was designed to hold 25 vials which contained either different (between 0 and 19.77 mmol/L) or constant (1.2 mmol/L) concentrations of contrast agent. The vials of constant concentration were used to measure coil non uniformity. The vials of different concentrations were used to measure SI using different sequences and different TI and TS. The maximum linear relationship between corrected SI and concentration was found, where the square correlation R2 were equal to 0.95 and 0.99 . Results: This study shows that different sequences and different TI and TS can have an effect on the maximum linear relationship between SI and concentration . Conclusion: Regardless of the value of TI, TS and different IR and SR sequences chosen, the maximum linear relationship between SI and concentration is about twice that previously reported (i.e. 0.8 mmol/L) for measuring the blood flow. The higher dose will improve SNR in perfusion images

کلیدواژه ها:

T1-weighted image ، Inversion recovery ، Saturation recovery ، Signal intensity ، Concentration of contrast agent