title: Averaging keyhole pulse sequence with presaturation pulses and EXORCYCLE phase cycling for dynamic contrast-enhanced MRI.
abstract: The purpose of this study was to design a keyhole pulse sequence for quantitative 2D dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) based on a spoiled gradient echo T1-weighted acquisition. Saturation recovery was applied to achieve a linear correlation between signal intensity and contrast agent concentration in an arterial input function (AIF) while simultaneously removing time-of-flight effect. To remove ghosting artifacts arising from incomplete presaturation, EXORCYCLE phase cycling with averaging was applied to the pulse sequence. RF spoiling by radiofrequency switching with the synthesizer can be combined with EXORCYCLE phase cycling. Images affected by the large difference in signal intensity before and after contrast agent administration with the keyhole technique were improved by interleaving of peripheral lines of k-space with groups of central lines. Both peripheral and central lines were renewed during the dynamic scan. AIFs were obtained from the rat abdominal aorta with this keyhole sequence.
authors.affiliation: AstraZeneca, Global Sciences and Information, Macclesfield, Cheshire, UK. hideto.kuribayashi@varianinc.com
authors.forename: Hideto
authors.initials: H
authors.lastname: Kuribayashi
authors.forename: Daniel P
authors.initials: DP
authors.lastname: Bradley
authors.forename: David R
authors.initials: DR
authors.lastname: Checkley
authors.forename: Philip L
authors.initials: PL
authors.lastname: Worthington
authors.forename: Jean J
authors.initials: JJ
authors.lastname: Tessier
mesh_terms: D000818:Animals; D001012:Aorta, Abdominal / Q000033:anatomy & histology*; D016477:Artifacts; D003287:Contrast Media / Q000008:administration & dosage; D019786:Gadolinium DTPA / Q000008:administration & dosage; D008279:Magnetic Resonance Imaging / Q000379:methods*; D019047:Phantoms, Imaging; D051381:Rats
chemical_list: D003287:Contrast Media; D019786:Gadolinium DTPA