That air appears as a contrasting medium in the ventricles of the brain in roentgenograms of the skull was accidentally discovered by Luckett,1 in 1913. Dandy,2 in 1918, was the first to use air intentionally, when he introduced the gas directly into the ventricles. In 1919 he3 injected air into the lumbar subarachnoid space to outline cerebral structures on the roentgenogram. This procedure he called encephalography. To avoid confusion with electroencephalography, it may better be designated as pneumoencephalography. If no block exists, the pneumoencephalographic method provides for admission of air into any intracranial space occupied by cerebrospinal fluid.
In this paper there is described a simple automatic pneumoencephalograph which can be improvised from materials usually at hand in any hospital. Any two receptacles, a length of rubber tubing and one of glass, two lumbar puncture needles and two needle adapters comprise all that is necessary. Two
Osborne RL. A SIMPLE AUTOMATIC PNEUMOENCEPHALOGRAPH. Arch NeurPsych. 1944;51(4):405. doi:10.1001/archneurpsyc.1944.02290280103008