A case of subarachnoid hemorrhage due to rupture of a post-traumatic vertebral artery aneurysm.

Post-traumatic intracranial vertebral artery (VA) aneurysms are rare but clinically significant causes of fatal subarachnoid hemorrhage (SAH). We report a case of a woman in her 50s found dead following reported physical assaults. Histological analysis of the right VA revealed a traumatic aneurysm with two discrete sites of intimal and medial lesion within a single cross-section. Although one site had ruptured, the other remained as an unruptured mural defect. Both sites showed signs of acute inflammation with neutrophilic infiltration without fibrosis, indicating that a vital reaction occurred shortly before death. These findings provide morphological evidence that traumatic mechanical stress can induce multi-focal structural degradation rather than a localized, single-point failure. This case helps to understand the pathophysiological spectrum of traumatic vascular injuries in forensic practice.