Comparative Study of MRI Images in Accordance with Gradient Power Changes

Abstract

However, many hospitals conduct examinations based on the initial setting of gradient applied to the equipment, without altering the gradient setting for the area under examination based on its characteristics. Accordingly, this study measures the signal intensity and changes in imaging according to changes in MRI gradient power appropriate for T1 and T2 examination, for possible utilization as basic data for gradient power research and studies in MRI. Bottle Phantom was positioned inside the head & neck coil, and the T1-T2Brain Sequence was used for measurement. In the case of T2, the Repetition TR was fixed at 4,500 msec, and changes were applied to the TE in five incremental steps to obtain the measurement. In addition, for T1, TR 500 msec was fixed, and changes were applied to the TE in four incremental steps in obtaining the measurement. For SNR and CNR, Image J was used and the standard deviation. Matlab was used to measure PSNR and UACI. Image evaluation in accordance with the change in gradient power at T2. In the case of SNR,normal SLT was the highest at TE 60 msec with 581.4 for Fine SLT, at TE 60 msec with 623.1, in the case of Low SAR, at TE 80 msec with 610.2 was the highest. It was evident that SNR decreased with TE increase. 4 Image evaluation at T1 in accordance with the change in gradient power SNR for normal SLT was found to be the highest at TE 40 msec with 495.5, and TE 30 msec was found to be the lowest. Fine SLT was found to be the highest at TE 30 msec with 485.6, and low SAR was found to be the highest at TE 40 msec with 503.0. In the case of PSNR, for Normal SLT, it was the largest at TE 40 msec with24.1, without anysignificant difference from TE 10 to 30 msec. Determination of MRI signal intensity in accordance with changes in gradient power suggests that in the case of T2, the intensity of all the signals decreased when the TE was 80msec and above. In addition, the intensity of all the signals varied after changing the gradient power. In the case of T1, the signal intensity appeared to be strong at TE 40 msec. In T2, the intensity of all of the signals varied with the gradient power.