THE FUTURE IS MRI: ENHANCING ACUTE STROKE DIAGNOSTICS WITH ADVANCED IMAGING

Objectives
To highlight recent advancements in the use of MRI for acute ischemic stroke diagnostics, focusing on shortened
examination protocols, improved handling of traditional contraindications, increased accessibility and affordability, and the
growing potential of non-contrast imaging approaches.
Materials and Methods
We reviewed and analyzed current MRI applications in acute ischemic stroke, focusing on their use within the therapeutic
time window. Emphasis was placed on the clinical utility of key MRI sequences. We explored the development of rapid,
stroke-adapted protocols for emergency use and recent advances that improve MRI practicality—such as shortened scan
times, reduced need for contrast agents and increased availability of MRI, enhanced collaboration with cardiologists, newly
developed clinical guidelines, improved compatibility with implanted devices.
Results
MRI offers high sensitivity and specificity in detecting acute ischemic strokes, excelling in visualizing ischemic cores and
posterior fossa infarcts—without ionizing radiation. Technological advances have significantly improved MRI’s role in acute
stroke care. Portable head MRI systems now allow on-site imaging within stroke units, and the development of shortened
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BALCONE 2025, 6-8 November, Riga, Latvia
protocols has made MRI more compatible with acute stroke workflows. Standard clinical protocols last 10-11 minutes, while
3T MRI with artificial intelligence (AI) enables ultrafast stroke protocols of about 7–8 minutes.
Modern MRI protocols incorporate sequences such as DWI, FLAIR, GRE/SWI, 3D-TOF angiography, DSC perfusion, and
ASL. ASL, in particular, enables perfusion imaging without the use of contrast agents, which is especially useful in patients
with renal insufficiency or gadolinium contraindications.
The FLAIR/DWI mismatch is a widely used protocol in neurology to estimate stroke age and tissue viability in cases with
unclear onset. DWI/perfusion and DWI/ASL are also used to assess the ischemic core and penumbra, enabling more
individualized treatment decisions—especially in extended time windows. DWI and ADC maps are central to early ischemic
detection. Studies have proposed ADC thresholds (<520 × 10⁻⁶ mm²/s) to define non-viable tissue, with extremely low ADC
values linked with higher hemorrhagic transformation risk. A DWI-ASPECTS score of ≤4 or a diffusion lesion volume
(VolDWI) ≥71 mL has been associated with a substantially higher risk of hemorrhagic imbibition post-reperfusion. These
markers play a crucial role in patient selection for reperfusion therapies.
While CTA better assesses large vessels and collaterals, MRI is gaining clinical relevance with improved speed, advanced
imaging capabilities, and early tissue characterization for acute stroke care.
Conclusions
MRI provides diagnostic accuracy comparable to CT in acute ischemic stroke caused by large vessel occlusion while
offering superior sensitivity for detecting infarcts in the posterior fossa and more precise visualization of the ischemic core.
Recent advances have reduced traditional MRI contraindications. The integration of multiple MRI sequences enhances
patient selection for reperfusion therapies and improves risk stratification for hemorrhagic transformation. Furthermore, the
development of shortened MRI protocols, portable MRI technologies, and AI tools promises broader MRI accessibility and
rapid, potentially transforming acute stroke management workflows in the near future