ABSTRACT
The development of CT in 1971, and later MRI, revolutionised imaging of the brain by displaying anatomical detail as had never previously been available. In the pre-CT era the only technique for direct imaging of the brain parenchyma was radionuclide scanning, which yielded limited anatomical information. Other tests included plain radiographs to detect calcification or skull trauma, air encephalography to show the ventricles and angiography to demonstrate blood vessel architecture; the latter two tests carried considerable risk of side-effects and complications.
