Survival after traumatic ponto-medullary tear.

Two children (aged 10 and 12 years) were admitted unconscious to the neurosurgical department after traffic accidents. Both developed a 6th nerve paralysis on the next day. One patient was able to communicate from the 2nd day and died on the 8th day in an anuric state without major neurological deficit. The second patient remained deeply comatose, tetraplegic, and required intermittent artificial respiration: She died of pneumonia on the 26th day. Neuropathological examination revealed a ponto-medullary rent in each case: additionally there was avulsion of small arteries over the pyramids, haemorrhage and small focal infarcts in the distribution of perforating arteries in the medulla and pons, and abundant retraction balls in longitudinal fibre tracts of the brain stem. The cases show for the first time that traumatic ponto-medullary tears are not always rapidly fatal, and demonstrate that primary focal brain stem trauma may occur in the absence of diffuse trauma of the white substance.