title: Perimesencephalic subarachnoid hemorrhage: Etiologies, risk factors, and necessity of the second angiogram.
abstract: OBJECTIVE
  In this paper, we aim to present our experience with a series of patients with PMSAH. In addition, the clinical course of perimesencephalic subarachnoid hemorrgade (PMSAH) is discussed with an evaluation of etiologies, risk factors, and the necessity for a second angiogram on follow-up.
  
  
  METHODS
  The data for this study were obtained retrospectively from patients who were treated at the Uludag University, School of Medicine, Department of Neurosurgery, Division of Neurovascular Surgery's clinic with a diagnosis of PMSAH between January 1980 and March 2002.
  
  
  RESULTS
  We identified a total of 24 patients, 12 male. The mean age at the time of hemorrhage was 53 ± 12 years. In all patients, the onset was typical with a sudden severe headache. Five of the patients were Hunt-Hess Grade I, 15 were Grade II, and 4 were Grade III. The initial 4-vessel angiography was normal in 23 cases. Twenty-two had a second 4-vessel angiography, and all were normal. We observed acute hydrocephalus in 5 patients (20.8%). We did not observe re-bleeding during the follow-up of our patients.
  
  
  CONCLUSIONS
  Patients with PMSAH have a particularly excellent outcome, and there is no need to evaluate these patients with repeat angiography.
authors.affiliation: Department of Neurosurgery, Kocaeli Derince Training and Research Hospital, Kocaeli, Turkey.
authors.forename: Soner
authors.initials: S
authors.lastname: Şahin
authors.affiliation: Department of Neurosurgery, Edirne State Hospital, Edirne, Turkey.
authors.forename: Emre
authors.initials: E
authors.lastname: Delen
authors.affiliation: Department of Neurosurgery, Uludag University, Bursa, Turkey.
authors.forename: Ender
authors.initials: E
authors.lastname: Korfali
keywords: Perimesencephalic hemorrhage; repeat cerebral angiography; subarachnoid hemorrhage