Acute responses to blunt head trauma. Experimental model and gross pathology.

This study of blunt craniocerebral trauma describes an experimental model that involves delivery of forceful blows to the resting movable skulls of anesthetized cats. Injuries inflicted by this method included skull fractures in 81% of cases, epidural hemorrhages in 50%, subdural hemorrhages in 80%, subarachnoid hemorrhages in 100%, and brain contusions in 84%. In the majority of instances the subdural and epidural hemorrhages were thin films of blood that did not compress or distort the subjacent brain. The distribution of cerebral contusions was restricted to the cerebral parenchyma beneath the locus of cranial impact except for contusions associated with skull fractures. This experimental model recapitulates clinically realistic human cranial trauma and produces pathological lesions suitable for investigation of the pathophysiology of blunt head trauma.