Acute stroke magnetic resonance imaging: current status and future perspective

Area of Science:

• Neurology
• Radiology
• Medical Imaging

Background:

• Cerebral stroke is a leading cause of death and disability, primarily due to ischemic events from arterial occlusion.
• Current thrombolysis guidelines for acute ischemic stroke are time-window dependent, potentially overlooking salvageable brain tissue.
• Individual collateral blood flow, not just time, determines the extent of potentially salvageable ischemic tissue (penumbra).

Purpose of the Study:

• To review the current status of magnetic resonance imaging (MRI) in acute stroke imaging, with a focus on ischemic stroke.
• To illustrate the principles and diagnostic value of various MRI sequences in relation to cerebral ischemia pathophysiology.
• To discuss MRI's role in differential diagnoses, acute treatment selection, and monitoring of stroke therapy.

Main Methods:

• Review of current literature on MRI techniques for acute stroke imaging.
• Focus on diffusion-weighted imaging (DWI) and perfusion imaging (PI) with parameter maps for differentiating infarct core and penumbra.
• Discussion of MRI sequences relevant to ischemic stroke and its differential diagnoses.

Main Results:

• MRI, particularly DWI and PI, enables differentiation between infarct core and penumbra.
• This differentiation allows for patient selection based on physiological parameters, moving beyond fixed time windows for treatment.
• MRI techniques are valuable for diagnosing various stroke types and monitoring treatment response.

Conclusions:

• MRI is a powerful tool for acute ischemic stroke imaging, providing critical physiological information.
• Advanced MRI techniques facilitate redefined patient selection for reperfusion therapies.
• MRI plays a vital role in guiding acute stroke treatment and monitoring long-term recovery.