Effectiveness of a Tailored Anterior Saturation Band in the Improvement of the Image Quality of Pelvic Magnetic Resonance for Assessing Rectal Cancer
We sought to test the effectiveness of the application of a tailored anterior saturation band (ASB) to improve the image quality of pelvic magnetic resonance imaging (MRI) for assessing rectal cancer.Methods:
A total of 165 patients with MRI assessment of rectal cancer between 2013 and 2015 were included. The image quality scores (4-point scale: 1, nondiagnostic through 4, excellent) of MRI without and with tailored ASBs were compared. Sensitivity, specificity, positive and negative predictive values, and accuracy of pelvic MRIs with and without a tailored ASB for T-staging in 65 patients with direct surgery and 67 patients with chemoradiotherapy before surgery were evaluated.Results:
Two independent raters exhibited moderate-to-excellent interobserver agreements (κ = 0.529-0.879) in the grading of MRI image quality. Overall, the quality scores of sagittal and axial T2-weighted images with tailored ASBs were significantly improved compared with MRIs without ASBs (3.5 ± 0.3 vs. 2.7 ± 0.8 [mean ± SD]; P < .001, and 3.6 ± 0.3 vs. 2.8 ± 0.8; P < .001, respectively). The application of tailored ASBs in MRIs improved the averaged accuracies for staging of ≤ T2, T3, and T4 tumors from 87.7%, 78.5%, and 90.8% to 93.1%, 86.9%, and 97.7%, respectively. In post-chemoradiotherapy MRI follow-ups, the use of tailored ASBs also improved the average accuracies for staging of yT0, yT1-2, yT3, and yT4 tumors from 80.6%, 73.1%, 73.9%, and 91.0%, to 85.8%, 82.9%, 85.1%, and 94.0%, respectively.Conclusions:
Application of a tailored ASB in pelvic MRI is effective in substantially reducing motion artifacts, significantly upgrading image quality, and improving accuracies of rectal tumor staging.
Pelvic magnetic resonance imaging is useful for the pretreatment assessment of rectal cancer, but motion artifacts can compromise clear tumor delineation. We tested the effectiveness of the application of a tailored anterior saturation band to improve the image quality of magnetic resonance imaging. This technique is effective in reducing motion artifacts with significant improvement of image quality and accuracies of rectal tumor staging.