Intracranial arterial dissection is a rare cause of stroke. In the adult population, posterior circulation is more commonly involved than anterior circulation [1], [2]. The intracranial vertebral artery is the most common artery involved in adults [3]. Even as such, intracranial vertebral artery dissection (iVAD) is an uncommon cause of stroke overall, and an even rarer cause of spontaneous subarachnoid hemorrhage (SAH). Its exact incidence remains unknown; however, vertebrobasilar dissection accounts for 3%–7% of subarachnoid hemorrhage (SAH) cases [1]. The prognosis of this condition is uncertain, even with contemporary medical practices. This is largely due to the increased likelihood of early rebleeding in these cases [4], [5]. The mortality rate associated with intracranial vertebral artery dissection (iVAD) is notably high, varying between 19% and 83% [39]. Over the past few decades, the approach to treatment has shifted towards the neuro-interventional arm; controversies still remain as to which endovascular technique to use to prevent rebleeding, and to whether revascularization surgery is indicated.

This paper provides a summary based on a review of patients who arrived at our center with SAH due to iVAD, alongside an analysis of current literature on the subject. Among 1078 patients admitted with spontaneous SAH at the CHUM from 2016 to 2022, 22 cases (2%) were attributed to unilateral intradural VAD. In the same timeframe, we reviewed 103 cases of vertebro-basilar system dissections. Out of these, 32 patients presented exclusively with SAH, while the majority displayed predominantly ischemic symptoms. Among these 32 SAH patients, after excluding those with posterior inferior cerebellar artery (PICA) dissections, dissections extending into the basilar artery, and 2 pregnant women with bilateral VAD and SAH from other causes, 22 were identified as cases of unilateral intradural vertebral artery (VA) dissection. Our literature search found 10 series published in the past five years, each including a minimum of five consecutive patients, where detailed individual clinical data, treatment approaches, and/or outcomes were provided.

Topics addressed in this paper are the following:

How to treat

Anatomical considerations as pertaining to vertebral artery dissection and treatment

Pathophysiological mechanisms involved and histological findings in vertebral artery dissection

Epidemiology, risk factors, clinical presentation, natural history and work-up

Treatment strategies including endovascular techniques as well as indications for open surgery

Outcomes