Should less motion sensitive T2-weighted BLADE TSE replace Cartesian TSE for female pelvic MRI?

OBJECTIVES: To prospectively compare the diagnostic performance of a non-Cartesian k-space sampling T2-weighted TSE BLADE sequence with a conventional T2-weighted TSE sequence in female pelvic organs. METHODS: Forty-seven patients with sonographically indeterminate adnexal masses or uterine lesions underwent sagittal BLADE and conventional TSE at 1.5 T after glucagon administration. Two radiologists independently determined their preferred sequence by rating: overall image diagnostic quality, conspicuity of the zonal anatomy and delineation of pathologies of the uterus and cervix, presence of artefacts, and of fluid in the pouch of Douglas (Wilcoxon signed rank test). Signal-to noise ratios (SNRs) and contrast-to-noise ratios (CNRs) were measured for the myometrium versus the rectus abdominis muscle (Student’s t-test). RESULTS: BLADE significantly (p < 0.0001) reduced motion and ghosting artefacts and showed improved conspicuity (p = 0.3/0.24), but overall image quality did not differ significantly (inter-observer agreement BLADE κ = 0.89; TSE κ = 0.84). In the majority of cases (53.2 % vs 59.6 %, respectively, κ = 0.82) radiologists preferred conventional TSE due to better image contrast (p < 0.0001) and visibility of free pelvic fluid (p ≤ 0.0001). SNR (TSE 57.5 ± 37.7; BLADE 16.6 ± 12.2) and CNR (TSE 40.4 ± 33.5; BLADE 7.2 ± 8.8) were significantly higher on conventional TSE (p < 0.0001). CONCLUSIONS: Although BLADE reduces motion artefacts and provides a clearer delineation of uterine zonal anatomy compared with conventional TSE, this comes at the expense of overall contrast. MAIN MESSAGES: • Use of BLADE may reduce T2 contrast and thus visibility of free pelvic fluid or cystic structures • Non-Cartesian sampling of k-space such as BLADE is beneficial due to less motion sensitivity • BLADE provides clearer delineation and conspicuity of uterine zonal anatomy on pelvic MRIs