Abstract

Introduction: Pretruncal non-aneurysmal subarachnoid hemorrhage (PNSAH) is a rare subtype of subarachnoid hemorrhage (SAH) with a generally favorable prognosis and low complication rates. This study aimed to retrospectively evaluate the clinical and radiological features, treatment strategies, and outcomes of patients diagnosed with PNSAH in our institution.

Materials and Methods: A total of 11 patients diagnosed with PNSAH between 2020 and 2025 at the Department of Neurosurgery, Istanbul University Faculty of Medicine, were included in this retrospective study. All patients underwent computed tomography (CT) and digital subtraction angiography (DSA) to rule out aneurysmal pathology. Clinical status was assessed using the World Federation of Neurosurgical Societies (WFNS) grading system. Treatment modalities, complications, and outcomes were analyzed. Functional outcomes were evaluated using the modified Rankin Scale (mRS).

Results: Of the 11 patients, 55% were male and 45% female. The most common presenting symptom was sudden-onset severe headache (100%). Eight patients (72.7%) were classified as WFNS grade 1. Radiologically confirmed vasospasm was observed in five patients (45.5%), but no clinical or radiological ischemia developed. Acute hydrocephalus occurred in two patients (18.2%), both managed with external ventricular drainage (EVD); none required permanent shunt placement. According to mRS scores, 10 patients (90.9%) had favorable functional outcomes (mRS 0–2), while one patient (9.1%) experienced mortality.

Conclusion: PNSAH is a self-limiting hemorrhagic condition with an excellent prognosis when properly diagnosed and managed conservatively. Exclusion of aneurysmal sources and careful monitoring for complications such as vasospasm and hydrocephalus are essential. The findings of this study are consistent with the literature and support the adequacy of conservative treatment in most PNSAH cases.

Keywords: pretruncal subarachnoid hemorrhage, non-aneurysmal SAH, prepontine hemorrhage, subarachnoid hemorrhage

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Copyright © 2025 The Author(s). This is an open access article distributed under the Creative Commons Attribution License (CC BY), which permits unrestricted use, distribution, and reproduction in any medium or format, provided the original work is properly cited.

How to cite

1.
Gülsever Cİ, Dölen D, Andıç E, Dolaş İ, Aras Y, Şahin D. Pretruncal non-aneurysmal subarachnoid hemorrhage: A single-center retrospective evaluation. Sinir Sistemi Cerrahisi Derg 2025;10(1):19-25. https://doi.org/10.54306/sscd.2025.214