title: Volumetric Arterial Spin-labeled Perfusion Imaging of the Kidneys with a Three-dimensional Fast Spin Echo Acquisition.
abstract: OBJECTIVE
  Renal perfusion measurements using noninvasive arterial spin-labeled (ASL) magnetic resonance imaging techniques are gaining interest. Currently, focus has been on perfusion in the context of renal transplant. Our objectives were to explore the use of ASL in patients with renal cancer, and to evaluate three-dimensional (3D) fast spin echo (FSE) acquisition, a robust volumetric imaging method for abdominal applications. We evaluate 3D ASL perfusion magnetic resonance imaging in the kidneys compared to two-dimensional (2D) ASL in patients and healthy subjects.
  
  
  METHODS
  Isotropic resolution (2.6 × 2.6 × 2.8 mm(3)) 3D ASL using segmented FSE was compared to 2D single-shot FSE. ASL used pseudo-continuous labeling, suppression of background signal, and synchronized breathing. Quantitative perfusion values and signal-to-noise ratio (SNR) were compared between 3D and 2D ASL in four healthy volunteers and semiquantitative assessments were made by four radiologists in four patients with known renal masses (primary renal cell carcinoma).
  
  
  RESULTS
  Renal cortex perfusion in healthy subjects was 284 ± 21 mL/100 g/min, with test-retest repeatability of 8.8%. No significant differences were found between the quantitative perfusion value and SNR in volunteers between 3D ASL and 2D ASL, or in 3D ASL with synchronized or free breathing. In patients, semiquantitative assessment by radiologists showed no significant difference in image quality between 2D ASL and 3D ASL. In one case, 2D ASL missed a high perfusion focus in a mass that was seen by 3D ASL.
  
  
  CONCLUSIONS
  3D ASL renal perfusion imaging provides isotropic-resolution images, with comparable quantitative perfusion values and image SNR in similar imaging time to single-slice 2D ASL.
authors.affiliation: Beth Israel Deaconess Medical Center and Harvard Medical School, 330 Brookline Ave, AN-226, Boston, MA 02215. Electronic address: pmrobson98@gmail.com.
authors.forename: Philip M
authors.initials: PM
authors.lastname: Robson
authors.affiliation: University of Texas Southwestern Medical Center, Dallas, Texas.
authors.forename: Ananth J
authors.initials: AJ
authors.lastname: Madhuranthakam
authors.affiliation: Beth Israel Deaconess Medical Center and Harvard Medical School, 330 Brookline Ave, AN-226, Boston, MA 02215.
authors.forename: Martin P
authors.initials: MP
authors.lastname: Smith
authors.affiliation: Beth Israel Deaconess Medical Center and Harvard Medical School, 330 Brookline Ave, AN-226, Boston, MA 02215.
authors.forename: Maryellen R M
authors.initials: MR
authors.lastname: Sun
authors.affiliation: Beth Israel Deaconess Medical Center and Harvard Medical School, 330 Brookline Ave, AN-226, Boston, MA 02215.
authors.forename: Weiying
authors.initials: W
authors.lastname: Dai
authors.affiliation: University of Texas Southwestern Medical Center, Dallas, Texas.
authors.forename: Neil M
authors.initials: NM
authors.lastname: Rofsky
authors.affiliation: University of Texas Southwestern Medical Center, Dallas, Texas.
authors.forename: Ivan
authors.initials: I
authors.lastname: Pedrosa
authors.affiliation: Beth Israel Deaconess Medical Center and Harvard Medical School, 330 Brookline Ave, AN-226, Boston, MA 02215.
authors.forename: David C
authors.initials: DC
authors.lastname: Alsop
mesh_terms: D000328:Adult; D000368:Aged; D000465:Algorithms; D002292:Carcinoma, Renal Cell / Q000000981:diagnostic imaging; D005260:Female; D064368:Healthy Volunteers; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods; D021621:Imaging, Three-Dimensional / Q000379:methods*; D007668:Kidney / Q000000981:diagnostic imaging*; D007672:Kidney Cortex / Q000000981:diagnostic imaging; D007680:Kidney Neoplasms / Q000000981:diagnostic imaging*; D018810:Magnetic Resonance Angiography / Q000379:methods*; D008297:Male; D008875:Middle Aged; D055425:Respiratory-Gated Imaging Techniques; D059629:Signal-To-Noise Ratio; D013113:Spin Labels; D055815:Young Adult
chemical_list: D013113:Spin Labels
keywords: MRI; arterial spin labeling; blood flow; kidney disease; perfusion; renal cell carcinoma