Reversible diffusion-weighted imaging lesions in acute ischemic stroke: A systematic review

Area of Science:

• Neurology
• Radiology
• Medical Imaging

Background:

• Diffusion-weighted imaging (DWI) is crucial for acute ischemic stroke diagnosis.
• Reversible lesions on DWI (DWIR) represent a specific imaging finding with potential prognostic value.
• Understanding DWIR prevalence and significance aids in stroke management and outcome prediction.

Purpose of the Study:

• To systematically review the literature on reversible diffusion-weighted imaging (DWIR) lesions.
• To determine the prevalence, predictors, and clinical significance of DWIR in acute ischemic stroke.
• To evaluate the association of DWIR with reperfusion and clinical outcomes.

Main Methods:

• Systematic literature review of studies meeting specific DWI and follow-up imaging criteria.
• Inclusion criteria: DWI within 24 hours of stroke onset, follow-up DWI/FLAIR/T2 within 7/90 days.
• Data abstraction included clinical, imaging, and outcomes data.

Main Results:

• Twenty-three studies met inclusion criteria; DWIR prevalence was 26.5% (DWI-based) and 6% (FLAIR/T2-based).
• DWIR was associated with recanalization/reperfusion, earlier or timely treatment (t-PA, endovascular), and less severe perfusion deficits.
• DWIR correlated with early neurologic improvement (5/6 studies) and good long-term outcomes (6/7 studies), likely due to reperfusion.

Conclusions:

• Reversible diffusion-weighted imaging (DWIR) lesions occur in up to 25% of acute ischemic stroke patients.
• DWIR is a marker of reperfusion and is associated with favorable clinical outcomes.
• DWI alone may have limitations in defining the ischemic core in the early stroke phase.