antiptosis
/ˌæntɪptəˈsɪs, ˌæntɪpˈtɒsɪs/Definitions
1. noun
the downward displacement of the brain within the skull, often resulting from a severe head injury, usually associated with a concussion or other forms of traumatic brain injury
“The patient’s CT scan revealed antiptosis, prompting the doctor to perform emergency surgery.”