Traumatic acute subdural hematoma localized on the superior surface of the tentorium cerebelli--two case reports.

An 8-year-old boy, who fell downstairs and struck his head, and a 62-year-old female, who hit her head in the automobile accident, presented with unusual traumatic acute subdural hematoma localized on the superior surface of the tentorium cerebelli. Magnetic resonance imaging was useful for determination of the anatomical location of the hematoma, and confirmation of absence of significant parenchymal contusion. Injury of the variant bridging vein possibly caused subdural hematoma over the tentorium.