title: Quantification of supra-aortic arterial wall inflammation in patients with arteritis using high resolution dynamic contrast-enhanced magnetic resonance imaging: initial results in correlation to [18F]-FDG PET/CT.
abstract: OBJECTIVE
  : To compare [F]- -fluoro-D-glucose (FDG) positron emission tomography (PET)/computed tomography (CT), used in clinical routine to detect inflamed arteries in patients with arteritis, with high resolution dynamic contrast-enhanced (DCE) magnetic resonance imaging (MRI) in its ability to measure inflammation in carotid and vertebral arteries.
  
  
  METHODS
  : This study was performed with written informed consent, Health Insurance Portability and Accountability Act (HIPAA) compliance, and institutional review board approval. DCE-MRI of the carotid and vertebral arteries of 17 patients with suspected arteritis was acquired at 3T (2D saturation-recovery spoiled gradient echo, in plane resolution 0.625 × 0.625 mm) using a dedicated 4-channel carotid coil. Patients underwent [F] FDG-PET/CT within 1 week of the MRI scan. The blood pool-corrected mean standardized uptake value (mean target-to-background ratio [TBRmean]) was measured on PET/CT images at the identical location as the region-of-interest in the magnetic resonance images. MRI signal intensity data was analyzed to generate estimates of the tissue extraction fraction and interstitial volume using a 2-compartment model.
  
  
  RESULTS
  : [F]-FDG PET/CT TBRmean was significantly higher in patients with than without arteritis (1.55 ± 0.34 vs. 1.06 ± 0.14, P = 0.001). Patients diagnosed with arteritis had significantly higher extraction fractions as measured by DCE-MRI than patients without arteritis (8.79% ± 2.19% vs. 5.82% ± 1.13%, P = 0.002). TBRmean correlated significantly with the extraction fraction (r = 0.73, P < 0.001). DCE-MRI and FDG-PET/CT yielded the same sensitivity (86%) and specificity (90%) for the detection of arteritis. Intra- and interreader reproducibility was good with Intraclass Correlation Coefficients of 0.82 and 0.78, respectively.
  
  
  CONCLUSIONS
  : DCE-MRI is able to measure arterial inflammation reliably and noninvasively with good correlation to [F]-FDG PET/CT in patients suffering from arteritis of the supraaortic arteries.
authors.affiliation: Department of Clinical Radiology, University Hospitals Munich--Campus Grosshadern, Ludwig-Maximilians-University Munich, Germany. Clemens.Cyran@med.lmu.de
authors.forename: Clemens C
authors.initials: CC
authors.lastname: Cyran
authors.forename: Steven
authors.initials: S
authors.lastname: Sourbron
authors.forename: Katja
authors.initials: K
authors.lastname: Bochmann
authors.forename: Maximilian
authors.initials: M
authors.lastname: Habs
authors.forename: Thomas
authors.initials: T
authors.lastname: Pfefferkorn
authors.forename: Axel
authors.initials: A
authors.lastname: Rominger
authors.forename: José G
authors.initials: JG
authors.lastname: Raya
authors.forename: Maximilian F
authors.initials: MF
authors.lastname: Reiser
authors.forename: Martin
authors.initials: M
authors.lastname: Dichgans
authors.forename: Konstantin
authors.initials: K
authors.lastname: Nikolaou
authors.forename: Marcus
authors.initials: M
authors.lastname: Hacker
authors.forename: Tobias
authors.initials: T
authors.lastname: Saam
mesh_terms: D000368:Aged; D001167:Arteritis / Q000000981:diagnostic imaging / Q000473:pathology*; D002097:C-Reactive Protein; D002339:Carotid Arteries / Q000000981:diagnostic imaging / Q000473:pathology*; D016001:Confidence Intervals; D003287:Contrast Media; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D049268:Positron-Emission Tomography / Q000379:methods; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D018709:Statistics, Nonparametric; D014057:Tomography, X-Ray Computed / Q000379:methods; D014711:Vertebral Artery / Q000000981:diagnostic imaging / Q000473:pathology*
chemical_list: D003287:Contrast Media; D019788:Fluorodeoxyglucose F18; D002097:C-Reactive Protein