Diffusion-weighted imaging of pancreatic cancer at 3 tesla: Practical comparison of readout-segmented and single-shot echo-planar imaging for image quality.

[INTRODUCTION] The purpose of this study was to compare single-shot echo-planar imaging (SS-EPI) and readout-segmented echo-planar imaging (RS-EPI) for diffusion-weighted imaging (DWI) of pancreatic cancer at 3 T, with a focus on image quality relevant to routine clinical practice.

[METHODS] Forty-six patients with pathologically confirmed pancreatic cancer underwent 3-T magnetic resonance imaging (MRI) including SS-EPI and RS-EPI DWI. Quantitative image quality was assessed using signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), and apparent diffusion coefficient (ADC) values measured with regions of interest placed on pancreatic tumors and normal pancreas. A corrected RS-EPI (cRS-EPI) SNR was calculated to account for differences in spatial resolution. Qualitative assessments of lesion conspicuity and respiratory motion artifacts were performed on b-value of 800 s/mm images using a 5-point scale. Statistical comparisons were conducted using Student's t-test.

[RESULTS] There was no significant difference in SNR between SS-EPI and RS-EPI; however, cRS-EPI demonstrated significantly higher SNR. CNR was significantly higher with RS-EPI than with SS-EPI, while ADC values were comparable between the two techniques. RS-EPI improved lesion conspicuity, whereas SS-EPI was less affected by respiratory motion artifacts.

[CONCLUSION] RS-EPI provides improved lesion contrast and conspicuity with comparable ADC values relative to SS-EPI in pancreatic cancer DWI, while SS-EPI demonstrates greater robustness to respiratory motion.

[IMPLICATIONS FOR PRACTICE] Understanding the trade-off between image quality and motion robustness enables radiographers to select the most appropriate DWI sequence according to patient respiratory stability and clinical requirements, thereby optimizing pancreatic MRI protocols in routine clinical practice.