CT-findings in haemorrhages from aneurysms of the anterior communicating artery: correlation with angiography and clinical course.

CT findings, angiography and clinical course were analyzed in a series of 31 patients with a recent subarachnoid haemorrhage (SAH) from an aneurysm of the anterior communicating artery (ACoAA). It is shown that 3 types of bleedings can be distinguished according to the CT findings. In the first group (52%), suffering a mild or moderate bleeding into the basal cisterns and/or the cisterna lamina terminalis, the aneurysm mostly points downwards and is orientated straight in the midline, the Hunt and Hess Grade at admission is I or II and the prognosis following early surgery is good. In the second group (29%), the aneurysm mostly is orientated towards one side, additional bleeding occurs into the gyrus rectus and the mediobasal frontal lobe, they are in HH Grade II and III and the prognosis following surgery also is relatively good. In group three (19%) however, the aneurysm points upwards, they present with severe bleeding into the cisterna lamina terminalis, the cavum septum pellucidum and rupture into the putamen, hypothalamus and the ventricle. In this group, the HH grade at admission is IV or V and the prognosis is extremely unfavourable. It is concluded, that this classification may be used for decision on early surgery.