title: Navigated abdominal T1-W MRI permits free-breathing  image acquisition with less motion artifact.
abstract: T1-W imaging of the pediatric abdomen is often limited by respiratory motion artifacts. Although navigation has been commonly employed for coronary MRA and T2-W imaging, navigation for T1-W imaging is less developed. Thus, we incorporated a navigator pulse into a fat-suppressed T1-W SPGR sequence such that steady-state contrast was not disrupted. Ten children were scanned after gadolinium administration three times in immediate succession: breath-hold with no navigation, free-breathing with navigation, and free-breathing without navigation. Motion artifacts were scored for each sequence by two radiologists,showing fewer motion artifacts with navigation compared to free-breathing and greater motion artifacts than with breath-holding. This work demonstrates the feasibility and potential utility of navigation for pediatric abdominal T1-W imaging.
authors.affiliation: Department of Radiology, Lucile Packard Children's Hospital, Stanford University, Stanford, CA 94305-5913, USA. vasanawala@stanford.edu
authors.forename: Shreyas S
authors.initials: SS
authors.lastname: Vasanawala
authors.forename: Yuji
authors.initials: Y
authors.lastname: Iwadate
authors.forename: Daniel G
authors.initials: DG
authors.lastname: Church
authors.forename: Robert J
authors.initials: RJ
authors.lastname: Herfkens
authors.forename: Anja C
authors.initials: AC
authors.lastname: Brau
mesh_terms: D000005:Abdomen / Q000473:pathology*; D000293:Adolescent; D000328:Adult; D016477:Artifacts; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007089:Image Enhancement / Q000379:methods*; D007223:Infant; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D009068:Movement; D015203:Reproducibility of Results; D015656:Respiratory Mechanics; D012680:Sensitivity and Specificity