Systematic review of the cerebral angiograms of 446 head trauma patients (1971-1978) revealed the presence of an arteriovenous (AV) fistula of the middle meningeal artery (MMA) in 8 cases (1.8%), the total number of angiographically demonstrable injuries of the MMA being 18 (4%). AV fistulae of the MMA may prevent formation of epidural haematoma, but they are frequently associated with so severe damage to skull and brain that prognosis is nevertheless grave. A close relationship between the tighter adherence of the dura to bone in older age and development of an AV fistula of the MMA following trauma to the skull may be presumed.