Imaging Vascular Anatomy and Pathology of the Posterior Fossa

Abstract

Neurovascular diseases of the posterior circulation represent a major cause of morbidity and mortality, which is due in large part to the eloquence of the brainstem and cerebellum and the anatomical constraints of the posterior fossa. A sound understanding of posterior circulation vascular anatomy builds the foundation for the accurate diagnosis and appropriate management of posterior fossa neurovascular ischemic and hemorrhagic disease. This chapter begins with a brief overview of vertebral and basilar arterial anatomy, followed by a comprehensive discussion of brainstem and cerebellar vascular topography in the setting of ischemic stroke. The epidemiology, clinical presentation, prognostic factors, and natural history of brainstem and cerebellar ischemic stroke are highlighted. The second half of the chapter focuses on hemorrhagic diseases of the posterior fossa, reviewing recent data on saccular and fusiform posterior circulation aneurysms, with a focus on specific anatomical factors that influence both microsurgical and endovascular treatment. Subsequently, posterior fossa high-flow vascular malformations are reviewed with an emphasis on contemporary multimodal therapy and the unique clinico-anatomical challenges involved in treating these complex diseases. The chapter concludes with a practical discussion of the vascular imaging evaluation of posterior fossa ischemic and hemorrhagic stroke to aid the treating physician in the rapid and accurate diagnosis of common posterior fossa neurovascular disease.