[Perimesencephalic subarachnoid hemorrhage: clinical and computer tomography aspects].

AIM

The blood distribution on CCT and the prognosis of patients with nonaneurysmal subarachnoidal haemorrhage were retrospectively studied and compared to a patient group with aneurysmal haemorrhage.

METHODS

The blood distribution on CCT (72 h after bleeding episode) of 26 patients with nonaneurysmal subarachnoidal haemorrhage confirmed by two normal cerebral angiograms was compared to the blood distribution of 76 patients with aneurysmal haemorrhage. The clinical condition of these patients was further analysed, 4-60 months after the bleeding episode.

RESULTS

In 62% of patients with nonaneurysmal haemorrhage the blood distribution was perimesencephalic. The aneurysmal blood distribution pattern was more extended and only one patient showed a perimesencephalic pattern. 80% of the patients without aneurysms in angiography had no limitations in daily functional capacity.

CONCLUSION

The perimesencephalic pattern is frequently found in patients with nonaneurysmal subarachnoidal haemorrhage, the prognosis of these patients is excellent. Rarely is the perimesencephalic haemorrhage caused by a ruptured aneurysm. It needs thorough angiographic evaluation.