title: A feasible high spatiotemporal resolution breast DCE-MRI protocol for clinical settings.
abstract: Three dimensional bilateral imaging is the standard for most clinical breast dynamic contrast-enhanced (DCE) MRI protocols. Because of high spatial resolution (sRes) requirement, the typical 1-2 min temporal resolution (tRes) afforded by a conventional full-k-space-sampling gradient echo (GRE) sequence precludes meaningful and accurate pharmacokinetic analysis of DCE time-course data. The commercially available, GRE-based, k-space undersampling and data sharing TWIST (time-resolved angiography with stochastic trajectories) sequence was used in this study to perform DCE-MRI exams on thirty one patients (with 36 suspicious breast lesions) before their biopsies. The TWIST DCE-MRI was immediately followed by a single-frame conventional GRE acquisition. Blinded from each other, three radiologist readers assessed agreements in multiple lesion morphology categories between the last set of TWIST DCE images and the conventional GRE images. Fleiss' κ test was used to evaluate inter-reader agreement. The TWIST DCE time-course data were subjected to quantitative pharmacokinetic analyses. With a four-channel phased-array breast coil, the TWIST sequence produced DCE images with 20 s or less tRes and ~ 1.0×1.0×1.4 mm(3) sRes. There were no significant differences in signal-to-noise (P=.45) and contrast-to-noise (P=.51) ratios between the TWIST and conventional GRE images. The agreements in morphology evaluations between the two image sets were excellent with the intra-reader agreement ranging from 79% for mass margin to 100% for mammographic density and the inter-reader κ value ranging from 0.54 (P<.0001) for lesion size to 1.00 (P<.0001) for background parenchymal enhancement. Quantitative analyses of the DCE time-course data provided higher breast cancer diagnostic accuracy (91% specificity at 100% sensitivity) than the current clinical practice of morphology and qualitative kinetics assessments. The TWIST sequence may be used in clinical settings to acquire high spatiotemporal resolution breast DCE-MRI images for both precise lesion morphology characterization and accurate pharmacokinetic analysis.
authors: Diagnostic Radiology, Oregon Health & Science University, Portland, OR, USA.
authors: Luminita A
authors: LA
authors: Tudorica
authors: Karen Y
authors: KY
authors: Oh
authors: Nicole
authors: N
authors: Roy
authors: Mark D
authors: MD
authors: Kettler
authors: Yiyi
authors: Y
authors: Chen
authors: Stephanie L
authors: SL
authors: Hemmingson
authors: Aneela
authors: A
authors: Afzal
authors: John W
authors: JW
authors: Grinstead
authors: Gerhard
authors: G
authors: Laub
authors: Xin
authors: X
authors: Li
authors: Wei
authors: W
authors: Huang
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000792:Angiography; D001706:Biopsy / Q000379:methods; D001943:Breast Neoplasms / Q000175:diagnosis / Q000473:pathology*; D003287:Contrast Media / Q000493:pharmacokinetics / Q000494:pharmacology*; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008875:Middle Aged; D015588:Observer Variation; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D059629:Signal-To-Noise Ratio; D013269:Stochastic Processes; D013997:Time Factors
chemical_list: D003287:Contrast Media