[Intracranial cerebral herniations and secondary lesions in the brain stem]

Intracranial cerebral herniations with secondary lesions in the brain stem are reported. The secondary lesions founded on the upper brain stem of 23 encephala with cerebral herniations are described. Hemorrhages in arteries were seen in all the brains. The lesions points to a mechanical etiology, the caudal displacement of the brain stem being the most important factor. Areas of ischemic infarction were found in the brain stem in all the cases; it is suggested that they were produced by factors other than the causative of the hemorrhagic lesions.