gms | German Medical Science

62nd Annual Meeting of the German Society of Neurosurgery (DGNC)
Joint Meeting with the Polish Society of Neurosurgeons (PNCH)

German Society of Neurosurgery (DGNC)

7 - 11 May 2011, Hamburg

Special features of subarachnoid hemorrhage of unknown origin

Meeting Abstract

  • H. Maslehaty - Klinik für Neurochirurgie, Universitätsklinikum Schleswig-Holstein, Campus Kiel
  • H. Barth - Klinik für Neurochirurgie, Universitätsklinikum Schleswig-Holstein, Campus Kiel
  • A.K. Petridis - Klinik für Neurochirurgie, Universitätsklinikum Schleswig-Holstein, Campus Kiel
  • A. Doukas - Klinik für Neurochirurgie, Universitätsklinikum Schleswig-Holstein, Campus Kiel
  • H.M. Mehdorn - Klinik für Neurochirurgie, Universitätsklinikum Schleswig-Holstein, Campus Kiel

Deutsche Gesellschaft für Neurochirurgie. Polnische Gesellschaft für Neurochirurgen. 62. Jahrestagung der Deutschen Gesellschaft für Neurochirurgie (DGNC), Joint Meeting mit der Polnischen Gesellschaft für Neurochirurgen (PNCH). Hamburg, 07.-11.05.2011. Düsseldorf: German Medical Science GMS Publishing House; 2011. DocDI.10.11

doi: 10.3205/11dgnc175, urn:nbn:de:0183-11dgnc1753

Published: April 28, 2011

© 2011 Maslehaty et al.
This is an Open Access article distributed under the terms of the Creative Commons Attribution License ( You are free: to Share – to copy, distribute and transmit the work, provided the original author and source are credited.



Objective: Subarachnoid hemorrhage (SAH) of unknown origin can be differentiated into perimesencephalic (PM-SAH) and non-perimesencephalic SAH (NON-PM-SAH), where PM-SAH has clearly defined radiological features. We analyzed the data of 179 patients with SAH of unknown origin and present special features in respect to diagnostic evaluations, clinical course and outcome.

Methods: Retrospective analysis of all patients with SAH (1226 patients) in our department between January 1991 and December 2008. Included in the study were cases of spontaneous SAH with initially negative DSA. Patients with traumatic SAH and an unknown history were excluded from the study. Patients with initially negative DSA were divided into 2 groups: Group 1 with typically PM-SAH and Group 2 with NON-PM-SAH.

Results: 1068 patients were investigated with DSA, where the results were negative in 179 cases (47 with PM-SAH, 132 with NON-PM-SAH). The most frequent risk factors were arterial hypertension, coronary heart disease, overweight and diabetes mellitus in both groups. In contrast to patients with NON-PM-SAH, patients with PM-SAH were predominantly classified as Hunt & Hess grade 1 and 2 and as Fisher grade 2.

Second look DSA of 34 patients with PM-SAH revealed one aneurysm and DSA of 120 patients with NON-PM-SAH revealed an aneurysm in 15 cases.

MRI of the brain and the craniocervical region had 100% negative findings for non-aneurismal bleeding sources in all patients.

The clinical course of Group 2 had a significantly higher rate of complications as compared to Group 1. Cerebral vasospasm (CVS) with delayed ischemic neurological deficits (DIND) occurred exclusively in patients of Group 2. Three patients of Group 1 developed a mild and reversible CVS, but without DIND. The outcome was excellent in Group 1 with a Glasgow outcome score (GOS) of 4 and 5 for all patients. The outcome performance of patients with NON-PM-SAH was good in the majority of all cases, though 11 patients had a GOS of 3 and 13 patients died.

Conclusions: PM-SAH presented with a mild clinical course and an excellent outcome, without severe complications. In contrast to this, NON-PM-SAH has a significantly higher rate of dreaded complications, such as CVS and DIND and a mortality of about 10%. It is crucial to make a correct and exact diagnosis of PM-SAH, considering CT scanning during the first 24h after occurrence of symptoms and the radiological features.