Study on cases with posterior fossa epidural hematoma--clinical features and indications for operation.

In this retrospective study, 11 cases of posterior fossa epidural hematoma were analyzed in terms of clinical and radiological features, treatment, and outcome. Posterior fossa epidural hematomas accounted for 11.8% of all epidural hematomas encountered during the 7-year period studied. There were eight males and three females ranging in age from 2 to 53 years (mean, 20.7 years). Glasgow Coma Scale scores on admission were relatively good in many cases. Headache and/or vomiting were common symptoms on admission, whereas cerebellar signs were rare. As all 11 cases involved trauma, occipital fractures were present in eight (72.7%). Six patients underwent surgery. The indications for surgery, in terms of computed tomography findings, were: 1) the maximum thickness of the epidural hematoma was more than 15 mm; 2) the posterior fossa cisterns (e.g., the quadrigeminal and ambient cisterns) were poorly visualized; 3) there was marked deformity and/or displacement of the fourth ventricle; and 4) the hematoma extended to the supratentorial region and severely compressed the brain. At discharge, eight patients showed good recovery and one was moderately disabled. Two patients died. The prognosis for posterior fossa epidural hematoma appears relatively good, if it is not accompanied by severe primary brainstem injury and is diagnosed early, and appropriately and promptly treated.