title: Simultaneous measurement of hepatic and splenic stiffness using MR elastography: preliminary experience.
abstract: OBJECTIVE
  To compare MR elastography (MRE) using a single and a dual driver excitation for the quantification of hepatic and splenic stiffness (HS and SS), and to investigate the performance of HS and SS measured with single or dual driver excitation for the detection of liver cirrhosis in subjects with liver disease.
  
  
  METHODS
  This prospective HIPAA compliant and IRB approved study involved 49 subjects who underwent MRE at 3.0T, comparing three different acquisition methods (single driver on the liver, single driver on the spleen and dual driver acoustic excitation). A Mann-Whitney test was used to assess changes in stiffness values. Bland-Altman analysis was used to compare single and dual driver configurations for each organ. Performance for detection of liver cirrhosis was assessed using ROC analysis. Pearson correlation was used to estimate the dependence of HS and SS on spleen size.
  
  
  RESULTS
  There were 40 noncirrhotic and 9 cirrhotic patients. There was good agreement between stiffness values measured with a single or a dual driver (Bland-Altman limits of agreement -14.3 % to 18.9 % and -18.1 % to 29.7 %, CV 6.4 % and 9.4 %, for HS and SS. respectively). HS and SS were higher in subjects with liver cirrhosis (p < 0.001), with excellent detection performance (AUROC range 0.87-0.93). SS correlated strongly with spleen size (r = 0.69, p < 0.001), while HS showed weak correlation (r = 0.38, p = 0.006).
  
  
  CONCLUSIONS
  Using a dual acoustic driver configuration, hepatic and splenic stiffness can be simultaneously estimated with good concordance with single driver measurement.
authors.affiliation: Department of Radiology/Translational and Molecular Imaging Institute, Icahn School of Medicine at Mount Sinai, One Gustave Levy Place, Box 1234, New York, NY, 10029, USA.
authors.forename: Hadrien A
authors.initials: HA
authors.lastname: Dyvorne
authors.forename: Guido H
authors.initials: GH
authors.lastname: Jajamovich
authors.forename: Cecilia
authors.initials: C
authors.lastname: Besa
authors.forename: Nancy
authors.initials: N
authors.lastname: Cooper
authors.forename: Bachir
authors.initials: B
authors.lastname: Taouli
mesh_terms: D000328:Adult; D000368:Aged; D054459:Elasticity Imaging Techniques / Q000379:methods*; D005260:Female; D006801:Humans; D008099:Liver / Q000473:pathology*; D008103:Liver Cirrhosis / Q000473:pathology*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012372:ROC Curve; D015203:Reproducibility of Results; D013154:Spleen / Q000473:pathology*; D055815:Young Adult