Zhigang Wu^{1}, Yajing Zhang^{2}, Xiuquan Hu^{1}, Jing Zhang^{1}, Fei Zeng^{1}, Xiaofang Xu^{1}, Guangyu Jiang^{3}, Yan Zhao^{3}, Guillaume Gilbert^{4}, and Jiazheng Wang^{1}

^{1}Philips Healthcare, Beijing, China, ^{2}MR Clinical Science, Philips Healthcare (Suzhou), Suzhou, China, ^{3}MR R&D, Philips Healthcare (Suzhou), Suzhou, China, ^{4}Philips Healthcare, Precision Diagnosis, Hillmount, ON, Canada

Diffusion MRI could provide unique information non-invasively. However, it is still a technical challenge due to the intrinsic non-rigid motion during the cardiac cycle, displacement of the myocardium due to respiratory motion, field inhomogeneity, and short T1 and T2 values. Parallel imaging and Zoom imaging based on 2D RF (iZoom) could both reduce the distortion dramatically, second order flow compensated diffusion could be used to decrease the impact of motion. We propose a solution that combines iZoom, SENSE and the 2nd flow compensated diffusion to generate a robust cardiac diffusion MRI, its robustness was validated by a preliminary study.

Fig3 shows the ADC comparison for different schemes, it shows similar results, namely that full FOV DWI without FC

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Figure 1. Sequence diagram for iZoom with 2nd
order flow compensated diffusion encoding.

Figure
2. Diffusion weighted images by 4 schemes, b value equals 300s/mm2. (A) DWI
full FOV without 2nd order flow compensated diffusion gradient, (B) DWI
full FOV with 2nd order flow compensated diffusion gradient; (C) iZoom
without 2nd order flow compensated diffusion gradient, SENSE = 1.5;
(D) iZoom with 2nd order flow compensated diffusion gradient, SENSE
= 1.5.

Figure
3. ADC maps by 4 schemes, b value equals 300s/mm2. 4 ROI are compared. (A) DWI
full FOV without 2nd order flow compensated diffusion gradient, (B) DWI
full FOV with 2nd order flow compensated diffusion gradient; (C) iZoom
without 2nd order flow compensated diffusion gradient, SENSE = 1.5;
(D) iZoom with 2nd order flow compensated diffusion gradient, SENSE
= 1.5.

Table 1 Scan parameters for protocols

Table 2 Comparison of ADC values by 4 schemes for
different ROIs

DOI: https://doi.org/10.58530/2022/4137