PET procedure
A catheter was inserted in the radial artery for arterial blood sampling after testing for collateral blood flow and injection of 1% lidocaïne. A venous catheter was placed in the antebrachial vein of the other arm, for injection of [T1-weighted MRI scans of the brain were made using a 3 T Intera MRI scanner (Philips, The Netherlands), and were examined for abnormalities by an experienced neuroradiologist.