Optimising diffusion-weighted imaging in the abdomen and pelvis: comparison of image quality between monopolar and bipolar single-shot spin-echo echo-planar sequences

2010 ◽  
Vol 20 (10) ◽  
pp. 2422-2431 ◽  
Author(s):  
Stavroula Kyriazi ◽  
Matthew Blackledge ◽  
David J. Collins ◽  
Nandita M. deSouza
2021 ◽  
Vol 10 (2) ◽  
pp. 205846012199473
Author(s):  
Takeshi Yoshizako ◽  
Rika Yoshida ◽  
Hiroya Asou ◽  
Megumi Nakamura ◽  
Hajime Kitagaki

Background Echo-planar imaging (EPI)-diffusion-weighted imaging (DWI) may take unclear image affected by susceptibility, geometric distortions and chemical shift artifacts. Purpose To compare the image quality and usefulness of EPI-DWI and turbo spin echo (TSE)-DWI in female patients who required imaging of the pelvis. Material and Methods All 57 patients were examined with a 3.0-T MR scanner. Both TSE- and EPI-DWI were performed with b values of 0 and 1000 s/mm2. We compared geometric distortion, the contrast ratio (CR) of the myometrium to the muscle and the apparent diffusion coefficient (ADC) values for the myometrium and lesion. Two radiologists scored the TSE- and EPI-DWI of each patient for qualitative evaluation. Results The mean percent distortion was significantly smaller with TSE- than EPI-DWI ( p = 0.00). The CR was significantly higher with TSE- than EPI-DWI ( p = 0.003). There was a significant difference in the ADC value for the uterus and lesions between the EPI- and TSE-DWI ( p < 0.05). Finally, the ADC values of cancer were significantly different from those for the uterus and benign with both the two sequences ( p < 0.05). The scores for ghosting artifacts were higher with TSE- than EPI-DWI ( p = 0.019). But there were no significant differences between TSE- and EPI-DWI with regard to image contrast and overall image quality. Conclusion TSE-DWI on the female pelvis by 3T MRI produces less distortion and higher CR than EPI-DWI, but there is no difference in contrast and image quality.


2019 ◽  
Vol 30 (4) ◽  
pp. 1876-1884
Author(s):  
He An ◽  
Xiaodong Ma ◽  
Ziyi Pan ◽  
Hua Guo ◽  
Elaine Yuen Phin Lee

Abstract Objectives To qualitatively and quantitatively compare the image quality between single-shot echo-planar (SS-EPI) and multi-shot echo-planar (IMS-EPI) diffusion-weighted imaging (DWI) in female pelvis Methods This was a prospective study involving 80 females who underwent 3.0T pelvic magnetic resonance imaging (MRI). SS-EPI and IMS-EPI DWI were acquired with 3 b values (0, 400, 800 s/mm2). Two independent reviewers assessed the overall image quality, artifacts, sharpness, and lesion conspicuity based on a 5-point Likert scale. Regions of interest (ROI) were placed on the endometrium and the gluteus muscles to quantify the signal intensities and apparent diffusion coefficient (ADC). Signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), and geometric distortion were quantified on both sequences. Inter-rater agreement was assessed using κ statistics and Kendall test. Qualitative scores were compared using Wilcoxon signed-rank test and quantitative parameters were compared with paired t test and Bland-Altman analysis. Results IMS-EPI demonstrated better image quality than SS-EPI for all aspects evaluated (SS-EPI vs. IMS-EPI: overall quality 3.04 vs. 4.17, artifacts 3.09 vs. 3.99, sharpness 2.40 vs. 4.32, lesion conspicuity 3.20 vs. 4.25; p < 0.001). Good agreement and correlation were observed between two reviewers (SS-EPI κ 0.699, r 0.742; IMS-EPI κ 0.702, r 0.789). IMS-EPI showed lower geometric distortion, SNR, and CNR than SS-EPI (p < 0.050). There was no significant difference in the mean ADC between the two sequences. Conclusion IMS-EPI showed better image quality with lower geometric distortion without affecting the quantification of ADC, though the SNR and CNR decreased due to post-processing limitations. Key Points • IMS-EPI showed better image quality than SS-EPI. • IMS-EPI showed lower geometric distortion without affecting ADC compared with SS-EPI. • The SNR and CNR of IMS-EPI decreased due to post-processing limitations.


2014 ◽  
Vol 40 (1) ◽  
pp. 120-126 ◽  
Author(s):  
Andrew B. Rosenkrantz ◽  
Hersh Chandarana ◽  
Josef Pfeuffer ◽  
Michael J. Triolo ◽  
Mohammed Bilal Shaikh ◽  
...  

Sign in / Sign up

Export Citation Format

Share Document