title: Fast contrast-enhanced 4D MRA and 4D flow MRI using constrained reconstruction (HYPRFlow): potential applications for brain arteriovenous malformations.
abstract: OBJECTIVE
  HYPRFlow is a novel imaging strategy that provides fast, high-resolution contrast-enhanced time-resolved images and measurement of the velocity of the entire cerebrovascular system. Our hypothesis was that the images obtained with this strategy are of adequate diagnostic image quality to delineate the major components of AVMs.
  
  
  METHODS
  HYPRFlow and 3D TOF scans were obtained in 21 patients with AVMs with correlative DSA examinations in 14 patients. The examinations were scored for image quality and graded by using the Spetzler-Martin criteria. Mean arterial transit time and overlap integrals were calculated from the dynamic image data. Volume flow rates in normal arteries and AVM feeding arteries were measured from the phase contrast data.
  
  
  RESULTS
  HYPRFlow was equivalent to 3D-TOF in delineating normal arterial anatomy, arterial feeders, and nidus size and was concordant with DSA for AVM grading and venous drainage in 13 of the 14 examinations. Mean arterial transit time on the AVM side was 0.49 seconds, and on the normal contralateral side, 2.53 seconds with P < .001. Across all 21 subjects, the mean arterial volume flow rate in the M1 segment ipsilateral to the AVM was 4.07 ± 3.04 mL/s; on the contralateral M1 segment, it was 2.09 ± 0.64 mL/s. The mean volume flow rate in the largest feeding artery to the AVM was 3.86 ± 2.74 mL/s.
  
  
  CONCLUSIONS
  HYPRFlow provides an alternative approach to the MRA evaluation of AVMs, with the advantages of increased coverage, 0.75-second temporal resolution, 0.68-mm isotropic spatial resolution, and quantitative measurement of flow in 6 minutes.
authors.affiliation: From the Department of Radiology (W.C.), University of California, Los Angeles, Los Angeles, California.
authors.forename: W
authors.initials: W
authors.lastname: Chang
authors.affiliation: Medical Physics (Y.W., K.J., M.L., O.W., C.M.), University of Wisconsin School of Medicine, Madison, Wisconsin.
authors.forename: Y
authors.initials: Y
authors.lastname: Wu
authors.affiliation: Medical Physics (Y.W., K.J., M.L., O.W., C.M.), University of Wisconsin School of Medicine, Madison, Wisconsin.
authors.forename: K
authors.initials: K
authors.lastname: Johnson
authors.affiliation: Medical Physics (Y.W., K.J., M.L., O.W., C.M.), University of Wisconsin School of Medicine, Madison, Wisconsin.
authors.forename: M
authors.initials: M
authors.lastname: Loecher
authors.affiliation: Medical Physics (Y.W., K.J., M.L., O.W., C.M.), University of Wisconsin School of Medicine, Madison, Wisconsin.
authors.forename: O
authors.initials: O
authors.lastname: Wieben
authors.affiliation: Department of Radiology (M.E., C.O., P.R.), Université Paris-Descartes, Paris, France.
authors.forename: M
authors.initials: M
authors.lastname: Edjlali
authors.affiliation: Department of Radiology (M.E., C.O., P.R.), Université Paris-Descartes, Paris, France.
authors.forename: C
authors.initials: C
authors.lastname: Oppenheim
authors.affiliation: Department of Radiology (M.E., C.O., P.R.), Université Paris-Descartes, Paris, France.
authors.forename: P
authors.initials: P
authors.lastname: Roca
authors.affiliation: Department of Radiology (J.H.), Rikshospitalet, Oslo, Norway.
authors.forename: J
authors.initials: J
authors.lastname: Hald
authors.affiliation: Departments of Radiology (B.A.-K., P.T.).
authors.forename: B
authors.initials: B
authors.lastname: Aagaard-Kienitz
authors.affiliation: Neurosurgery (D.N.).
authors.forename: D
authors.initials: D
authors.lastname: Niemann
authors.affiliation: Medical Physics (Y.W., K.J., M.L., O.W., C.M.), University of Wisconsin School of Medicine, Madison, Wisconsin.
authors.forename: C
authors.initials: C
authors.lastname: Mistretta
authors.affiliation: Departments of Radiology (B.A.-K., P.T.) pturski@uwhealth.org.
authors.forename: P
authors.initials: P
authors.lastname: Turski
mesh_terms: D000328:Adult; D000368:Aged; D015901:Angiography, Digital Subtraction / Q000379:methods; D005260:Female; D006801:Humans; D002538:Intracranial Arteriovenous Malformations / Q000175:diagnosis*; D018810:Magnetic Resonance Angiography / Q000379:methods*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D059906:Neuroimaging / Q000379:methods*