Prognostic value of intraventricular blood in perimesencephalic nonaneurysmal subarachnoid hemorrhage

Introduction: Perimesencephalic nonaneurysmal subarachnoid hemorrhage (PNSH ) is a distinct type of subarachnoid hemorrhage with a characteristic bleed ing pattern, and an excellent clinical outcome. However. the clinical cours e of patients presenting with a perimesencephalic nonaneurysmal bleeding pa ttern and intraventricular blood has not vet been investigated. Materials and Methods: In this retrospective study we describe the cisterna l blood distribution and the clinical course of 34 PNSH patients with (10 p atients) and without (24 patients) intraventricular blood. Results/Discussion: Patients without intraventricular blood were in good cl inical condition on admission: the in-hospital course was uneventful except for acute hydrocephalus, which was detected in two cases and improved spon taneously in both patients. All patients resumed their previous lifestyles. In contrast, two patients with PNSH and intraventricular blood were drowsy and had focal neurologic deficits on admission. Four patients developed an acute hydrocephalus, and two of these patients needed ventricular shunting . There was evidence for delayed cerebral ischemia in one of these patients . Outcome was excellent in eight cases. and one patient was moderately and one patient was severely disabled at dismissal from the hospital. Rebleedin g did not occur in all patients, and repeated four-vessel angiography did n ot reveal the source of bleeding in any of our patients. Conclusion: Our data indicate that the presence of intraventricular blood m ay be a good indicator for the development of acute hydrocephalus in PNSH. Moreover. our results suggest that PNSH patients with ventricular blood may have a higher complication rate and a poorer outcome compared with PNSH pa tients without intraventricular blood.