Evaluation of traumatic subarachnoid haemorrhage on computed tomography.

Traumatic subarachnoid haemorrhage (TSAH) is a computed tomography (CT) scan finding frequently found in the acute phase of brain injury. However, the clinical evaluation of TSAH is controversial. The subjects in the present series consisted of 46 patients in whom the initial CT scan within 6 h after injury revealed a high density area in the subarachnoid space. The subjects were divided into three types: type 1 n = 10) had massive haemorrhage in the basal cisterns; type II (n = 9) had localized haemorrhage in the basal cisterns; and type III (n = 27) had localized haemorrhage in the cortical sulci or Sylvian fissure. The clinical and neuroradiological findings as well as the outcome of these three types of TSAH are discussed. The results of our study showed that TSAH observed at an acute stage of head trauma was associated with a great variety of intracranial pathological changes. Type I cases had either good or poor outcome, and diffuse brain injury was predominant in patients with poor outcome. The outcome was generally good in type II and III cases.