Current perspectives on neuroimaging techniques used to identify stroke mimics in clinical practice

ABSTRACT

Introduction

Urgent clinical assessment and brain imaging are essential for differentiating stroke mimics from stroke and to avoid unnecessary initiation of reperfusion and other therapies in stroke mimic patients.

Areas covered

In this article, the authors will review acute stroke imaging and then the imaging patterns of the most common stroke mimics. The authors have focused our review on brain CT scan, and more specifically CT perfusion, as this is the most commonly available and emerging tool in emergency settings. The authors also provide information on acute brain MRI and MR perfusion.

Expert opinion

Imaging can contribute to the detection and diagnosis of acute stroke mimics. Knowledge of imaging findings in different stroke mimics can help distinguish these from patients with stroke who require timely reperfusion therapy. CT and MRI perfusion and diffusion-weighted imaging (DWI) MRI are useful imaging modalities for the assessment of acute stroke patients as they provide more accurate information than plain CT scan. Some of these modalities should be available in the emergency setting. The authors recommended CT perfusion as a useful tool for stroke management and differentiation with stroke mimics.

KEYWORDS:

• Brain imaging
• mimics
• stroke
• CT scan and MRI

Article highlights

• Multimodal imaging of the brain with CT and MRI techniques has become an invaluable tool not only in the initial diagnosis of stroke, but also in differentiating stroke from stroke mimics.

• CT perfusion performs well in the diagnosis of common stroke mimics such as migraine and epilepsy.

• MRI performs better than CT scan in demyelinating disease, transient global amnesia, and metabolic encephalopathy.

• Migraine and seizure present with perfusion changes not restricted to a vascular territory.

• Decreased perfusion in migraine with aura is less severe than in ischemic penumbra.

• There is increased perfusion in epilepsy corresponding to increased metabolic demand.

Declaration of interest

The authors have no relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript. This includes employment, consultancies, honoraria, stock ownership or options, expert testimony, grants or patents received or pending, or royalties.

Reviewer disclosures

Peer reviewers on this manuscript have no relevant financial or other relationships to disclose.