Cardiac-gated phase MR imaging of aqueductal CSF flow.

The direction of CSF flow within the cerebral aqueduct was studied by cardiac-gated magnetic resonance (MR) phase images in five healthy volunteers and 10 patients with presumably normal cerebral CSF circulation. Caudal CSF flow was observed during systole and cranial flow during diastole. Using phantom based calibrations of the imager, aqueductal CSF velocities of 3-5 mm/s were calculated. Cardiac-gated phase MR is a potentially major tool for the investigation of the CSF circulation.