Readout-Segmented Echo-Planar Imaging in Diffusion-Weighted MR Imaging in Breast Cancer: Comparison with Single-Shot Echo-Planar Imaging in Image Quality

Abstract

ObjectiveThe purpose of this study was to compare the image quality of standard single-shot echo-planar imaging (ss-EPI) and that of readout-segmented EPI (rs-EPI) in patients with breast cancer.Materials and MethodsSeventy-one patients with 74 breast cancers underwent both ss-EPI and rs-EPI. For qualitative comparison of image quality, three readers independently assessed the two sets of diffusion-weighted (DW) images. To evaluate geometric distortion, a comparison was made between lesion lengths derived from contrast enhanced MR (CE-MR) images and those obtained from the corresponding DW images. For assessment of image parameters, signal-to-noise ratio (SNR), lesion contrast, and contrast-to-noise ratio (CNR) were calculated.ResultsThe rs-EPI was superior to ss-EPI in most criteria regarding the qualitative image quality. Anatomical structure distinction, delineation of the lesion, ghosting artifact, and overall image quality were significantly better in rs-EPI. Regarding the geometric distortion, lesion length on ss-EPI was significantly different from that of CE-MR, whereas there were no significant differences between CE-MR and rs-EPI. The rs-EPI was superior to ss-EPI in SNR and CNR.ConclusionReadout-segmented EPI is superior to ss-EPI in the aspect of image quality in DW MR imaging of the breast.

Comparison of readout segmented echo planar imaging (EPI) and EPI with reduced field‐of‐VIew diffusion‐weighted imaging at 3t in patients with breast cancer

“…Koyasu et al also reported that the distortion in DWI was significantly reduced with rs‐EPI than in ss‐EPI in both phantom and patient studies. The other studies about rs‐EPI of breast imaging demonstrated that rs‐EPI provided higher image quality and lesion conspicuity than ss‐EPI, thus rs‐EPI reached a higher diagnostic accuracy for the differentiation of benign and malignant breast lesions …”

“…However, there are techniques currently in use to minimize these drawbacks, such as twice‐refocused sequences to mitigate eddy current induced distortions, and reversed phase encoding techniques to mitigate susceptibility‐induced distortions . Several previous studies evaluated the quantitative and qualitative comparisons of the image quality between ss‐EPI and rs‐EPI . One study about DWI of the pediatric brain reported that rs‐EPI provided improved image quality compared to ss‐EPI .…”

“…29 Several previous studies evaluated the quantitative and qualitative comparisons of the image quality between ss-EPI and rs-EPI. [13][14][15][16][17][18] One study about DWI of the pediatric brain reported that rs-EPI provided improved image quality compared to ss-EPI. 13 Koyasu et al 18 also reported that the distortion in DWI was significantly reduced with rs-EPI than in ss-EPI in both phantom and patient studies.…”

“…Readout segmented EPI (rs-EPI) with 2D navigator echoes for reduced sensitivity to motion was introduced to reduce geometric distortions, image blurring, and ghosting artifacts in the human brain at 3T. [13][14][15][16][17][18] The spatial resolution of rs-EPI is still moderate and inferior to that of DCE-MRI. Reduced field-of-view (rFOV) EPI is another promising tool for the characterization of breast lesions.…”

Evaluation of Breast Cancer Morphology Using Diffusion‐Weighted and Dynamic Contrast‐Enhanced MRI: Intermethod and Interobserver Agreement

“…The less than perfect concordance with DCE MRI, which we set as a reference standard, implies a considerable gap in spatial resolution that needs to be addressed. However, this may be achievable, as several studies have demonstrated a significant improvement in parameters pertaining to image quality when either higher field strength, rs‐EPI, or rFOV techniques were employed . Most notably, Bogner et al indicated that DWI at 7T may enable morphological assessment of breast lesions by offering spatial resolution that is close to the recommendations for DCE MRI …”