title: High-resolution MRI in giant cell arteritis: imaging of the wall of the superficial temporal artery.
abstract: OBJECTIVE
  This study investigated the hypothesis that high-resolution MRI can reveal mural inflammatory changes of the superficial temporal artery in giant cell arteritis (GCA).
  
  
  METHODS
  MRI of the temporal artery of 20 patients with suspected GCA was performed on a 1.5-T scanner using a dedicated eight-element phased-array head coil. Contrast-enhanced multislice T1-weighted spin-echo sequences were acquired perpendicular to the orientation of the vessel, with a submillimeter spatial resolution of 0.2 x 0.3 mm and a slice thickness of 3 mm. Mural thickness and lumen diameter of the temporal artery were measured, and mural contrast enhancement was graded on a four-point scale by two radiologists. For all patients, the MRI results were compared with the findings of clinical examination and laboratory tests. In addition, biopsy samples of the temporal artery were taken from 16 of these patients.
  
  
  RESULTS
  MRI sharply demonstrated the superficial temporal artery, allowing an evaluation of its lumen and wall. Seventeen patients were GCA-positive according to criteria of the American College of Rheumatology. Of these 17, 16 had true-positive MRI findings and one had false-negative MRI findings. The 3 patients who were GCA-negative according to the American College of Rheumatology criteria had true-negative MRI findings. The mean thickness of the vessel wall and the lumen diameter were 0.88 +/- 0.23 mm and 0.78 +/- 0.29 mm, respectively, in GCA-positive patients and 0.57 +/- 0.25 mm and 0.7 +/- 0.1 mm, respectively, in GCA-negative patients.
  
  
  CONCLUSIONS
  High-resolution contrast-enhanced MRI of the temporal artery allowed visualization of the temporal artery and evaluation of possible inflammation of the vessel wall. Our initial results with this noninvasive technique agreed well with histologic results and with the clinical criteria of the American College of Rheumatology.
authors.affiliation: Department of Diagnostic Radiology, University of Freiburg, Hugstetter Strasse 55, Freiburg, BW 79106, Germany. bley@mrs1.ukl.uni-freiburg.de
authors.forename: Thorsten A
authors.initials: TA
authors.lastname: Bley
authors.forename: Oliver
authors.initials: O
authors.lastname: Wieben
authors.forename: Markus
authors.initials: M
authors.lastname: Uhl
authors.forename: Jens
authors.initials: J
authors.lastname: Thiel
authors.forename: Dieter
authors.initials: D
authors.lastname: Schmidt
authors.forename: Mathias
authors.initials: M
authors.lastname: Langer
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001706:Biopsy; D003287:Contrast Media; D003937:Diagnosis, Differential; D005260:Female; D019786:Gadolinium DTPA; D013700:Giant Cell Arteritis / Q000175:diagnosis*; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D013699:Temporal Arteries / Q000473:pathology*
chemical_list: D003287:Contrast Media; D019786:Gadolinium DTPA