The Use and Pitfalls of Intracranial Vessel Wall Imaging: How We Do It.

Intracranial vessel wall magnetic resonance (MR) imaging has gained much attention in the past decade and has become part of state-of-the-art MR imaging protocols to assist in diagnosing the cause of ischemic stroke. With intracranial vessel wall imaging, vessel wall characteristics have tentatively been described for atherosclerosis, vasculitis, dissections, Moyamoya disease, and aneurysms. With the increasing demand and subsequently increased use of intracranial vessel wall imaging in clinical practice, radiologists should be aware of the choices in imaging parameters and how they affect image quality, the clinical indications, methods of assessment, and limitations in the interpretation of these images. In this How I do It article, the authors will discuss the technical requirements and considerations for vessel wall image acquisition in general, describe their own vessel wall imaging protocol at 3 T and 7 T, show a step-by-step basic assessment of intracranial vessel wall imaging as performed at their institution-including commonly encountered artifacts and pitfalls-and summarize the commonly reported imaging characteristics of various intracranial vessel wall diseases for direct clinical applicability. Finally, future technical and clinical considerations for full implementation of intracranial vessel wall imaging in clinical practice, including the need for histologic validation and acquisition time reduction, will be discussed.