title: High resolution susceptibility weighted MR-imaging of brain tumors during the application of a gaseous agent.
abstract: OBJECTIVE
  To employ a high resolution blood oxygenation level dependent (BOLD) method called susceptibility weighted imaging (SWI) together with the breathing of carbogen to investigate the response of cerebral tumors to this breathing gas and to assess tumor anatomy at high resolution.
  
  
  METHODS
  Five patients with cerebral tumors (four glioblastoma multiforme, one astrocytoma [WHO grade II]) were studied using a susceptibility weighted 3D gradient echo, first order velocity compensated sequence (TE = 45 ms, TR = 67 ms, alpha = 25 degrees , FOV = 256 x 192 x 64 mm(3), typical matrix = 512 x 192 x 64), on a 1.5 T MR scanner while they were breathing air and carbogen. Signal changes between the two breathing conditions were investigated.
  
  
  RESULTS
  The glioblastomas showed strong but heterogeneous signal changes between carbogen and air breathing, with changes between + 22.4 +/- 4.9 % at the perimeter of the tumors and - 5.0 +/- 0.4 % in peritumoral areas that appeared hyperintense on T (2)-weighted images. The astrocytoma displayed a signal decrease during carbogen breathing (- 4.1 +/- 0.1 % to - 6.8 +/- 0.3 % in peritumoral areas that correspond to hyperintense regions on T (2)-weighted images, and - 3.1 +/- 0.1 % in the tumor-center).
  
  
  CONCLUSIONS
  SWI provides high resolution images of cerebral anatomy and venous vascularization. Combined with hypercapnia it allows for regional assessment of tumor activity.
authors: Institut für Diagnostische und Interventionelle Radiologie, Friedrich Schiller Universität Jena, Deutschland.
authors: A
authors: A
authors: Rauscher
authors: J
authors: J
authors: Sedlacik
authors: C
authors: C
authors: Fitzek
authors: B
authors: B
authors: Walter
authors: A
authors: A
authors: Hochstetter
authors: R
authors: R
authors: Kalff
authors: W A
authors: WA
authors: Kaiser
authors: J R
authors: JR
authors: Reichenbach
mesh_terms: D000328:Adult; D001254:Astrocytoma / Q000175:diagnosis; D001932:Brain Neoplasms / Q000175:diagnosis*; D002245:Carbon Dioxide; D003287:Contrast Media; D005260:Female; D005909:Glioblastoma / Q000175:diagnosis; D006801:Humans; D007089:Image Enhancement / Q000379:methods*; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D010100:Oxygen
chemical_list: D003287:Contrast Media; D002245:Carbon Dioxide; C011700:carbogen; D010100:Oxygen