Qualitative and Quantitative Comparison of Readout-Segmented and Single-Shot Echo-Planar Diffusion-Weighted MR Imaging of the Prostate At 3.0 T

Abstract

Abstract Aims and objectives The aim of the study is to qualitatively and quantitatively compare the diagnostic value of diffusion-weighted (DW) magnetic resonance (MR) imaging based on standard single-shot echo-planar imaging (ss-EPI) and readout-segmented echo-planar imaging in patients with prostate cancer at 3.0 Tesla. Materials and methods All patients referred with suspected prostate cancer, underwent multiparametric MR imaging (mpMRI) using our 3.0-T MR imager (Magnetom Skyra, Siemens Healthineers, Erlangen, Germany). In all patients, DW imaging was carried out first using ss-EPI and later using readout segmentation of long variable echo-trains (RESOLVE) sequence. RESOLVE is a type of multishot readout-segmented echo echo-planar imaging (rs-EPI) technique with an additional two-dimensional navigator for robust correction of motion-induced phase errors. Two independent readers visually assessed image quality, lesion conspicuity, and geometric distortions using a 5-point Likert scale. Image properties, such as signal-to-noise ratio, contrast-to-noise ratio, apparent diffusion coefficient (ADC) values, were also quantified. Results Both readers demonstrated good-to-excellent interreader agreement for the qualitative image-quality parameters. RESOLVE demonstrated significantly higher scores for overall image quality, lesion conspicuity, and reduced geometric distortion compared with ss-EPI (all p  < 0.05). Quantitatively, the mean SNR was significantly higher with RESOLVE than with ss-EPI (11.8 ± 4.3 vs. 9.2 ± 4.7, p  = 0.021). The mean contrast-to-noise ratio was also higher with RESOLVE (3.7 ± 4.2 vs. 3.0 ± 3.0), although the difference did not reach statistical significance ( p  = 0.055). Mean ADC was lower with RESOLVE than with ss-EPI (0.717 ± [SD] × 10  − 3 vs. 0.821 ± [SD] × 10  − 3  mm 2 /s), with no statistically significant difference ( p  = 0.058). Conclusion Compared with conventional ss-EPI, the use of rs-EPI for the acquisition of prostate diffusion-weighted imaging (DWI) resulted in significantly enhanced anatomical delineation, lesion conspicuity, and reduced geometric distortion. Therefore, rs-EPI could be an alternative to or replacement for ss-EPI for acquiring prostate DWI at 3.0 Tesla.