Acute stroke care in hospital settings with MRI capability
Key Highlights
DWI hyperintensities are not always indicative of irreversible infarction; lesion reversal can occur especially after reperfusion.
ADC thresholds (commonly 620 × 10–6 mm2/s) help distinguish salvageable penumbral tissue from infarct core but vary by brain region and imaging factors.
Over-reliance on a single ADC threshold risks misclassifying salvageable tissue, potentially excluding patients from reperfusion therapies.
Guideline-Based Recommendations
Diagnosis
Use diffusion-weighted MRI to detect early ischemic changes and assess lesion extent.
Calculate ADC maps from DWI to evaluate tissue viability and differentiate core from penumbra.
Consider physiological and technical variability in ADC values across brain regions and imaging platforms.
Management
Employ endovascular therapy rapidly in patients with salvageable tissue identified by DWI and ADC thresholds.
Avoid excluding patients from reperfusion therapies solely based on a fixed ADC threshold without considering clinical context.
Monitoring & Follow-up
Perform follow-up DWI imaging 12–36 hours post-EVT to assess lesion reversal and infarct evolution.
Use co-registration of pre- and post-EVT images to quantify lesion changes and validate ADC threshold predictions.
Risks
Misclassification of salvageable tissue as infarct core due to rigid ADC thresholds may lead to inappropriate treatment exclusion.
Variability in ADC measurements due to brain tissue heterogeneity and imaging differences can affect diagnostic accuracy.
Patient & Prescribing Data
Acute ischemic stroke patients undergoing EVT with pre- and post-treatment MRI
Rapid and successful recanalization within 2 hours of MRI is associated with potential lesion reversal detectable by ADC threshold analysis.
Clinical Best Practices
Use voxel-based ADC thresholding combined with clinical and imaging context rather than a single universal cutoff.
Exclude voxels with ADC values >760 × 10–6 mm2/s or <200 × 10–6 mm2/s to avoid artifacts in lesion assessment.
Ensure high-quality standardized DWI sequences and lesion segmentation with expert review to improve reliability.
Limit analysis to lesions >1 mL to reduce segmentation and co-registration inaccuracies.
Incorporate inter-rater reliability checks and consensus in lesion segmentation to enhance data validity.
by Thor Håkon Skattør, Atle Bjørnerud, Terje Nome, Kine Mari Bakke, Brian Anthony Enriquez, Ingrid Digernes, Cecilie Mørck Offersen, Mona Kristiansen Beyer, Geir Ringstad, Anne Hege Aamodt
