Three cases of communication syringomyelia secondary to midbrain gliomas.

Three cases of midbrain gliomas are descrbied clinically and pathologically. In each case high pressure symptoms were followed by visual disturbance and the onset of syringomyelia symptoms before death. All the patients had hydrocephalus. In one case with concomitant syringobulbia, the syrinx appeared to due to CSF communicating with the cord cavity through the tissues of the brain stem. In the other cases the communication between the CSF pathways and the syrinx was at the usual site, through the central canal at the obex.