Comparison of sagittal T2-weighted BLADE and fast spin-echo MRI of the female pelvis for motion artifact and lesion detection.

Abstract

The objective of this study was to evaluate the effectiveness of BLADE (proprietary name for periodically rotated overlapping parallel lines with enhanced reconstruction [PROPELLER] in MR systems from Siemens Healthcare) MRI compared with conventional T2-weighted fast spin-echo (FSE) MRI for reducing artifacts and improving image quality when imaging the female pelvis. Sagittal T2-weighted BLADE and FSE examinations of the pelvis of 26 women were performed on a 1.5-T scanner. Three radiologists assessed the images for the presence of artifacts, level of anatomic detail, and overall image quality using a modified Likert scale. Scores for each radiologist and each imaging sequence were analyzed with a linear mixed model, adjusting for correlation within radiologist and within patient. A quantitative comparison was conducted to investigate signal uniformity. The BLADE sequence was superior for evaluation of the junctional zone (p = 0.0019), delineation of ovarian borders and depiction of follicles (p < 0.0001), and detection of fibroids (p = 0.022). Overall image quality was improved with BLADE, with fewer respiratory motion artifacts. The BLADE sequence introduced "radial" artifact that was absent from the FSE images, but this artifact did not affect image quality. Quantitative analysis revealed mean coefficients of variation for BLADE and FSE in the uterus of 21.6% and 22.5%, respectively (p = 0.36). The mean coefficients of variation were 4.6% and 6.1% in fat (p = 0.0007), indicating less variation with BLADE. The mean acquisition times for the BLADE and FSE sequences were 4 minutes 31 seconds and 3 minutes 46 seconds, respectively. Imaging of uterine junctional zone anatomy, ovaries, and fibroids was improved and artifacts were reduced with BLADE compared with FSE. Radial artifact introduced by the BLADE sequence and slightly longer imaging times needed for the BLADE sequence were offset by improved image quality.