ASPECTS
Alberta Stroke Program Early CT Score — ischemic stroke CT scoring.
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Why use it
Standardizes early ischemic change assessment on non-contrast CT. Score <6 associated with poor outcome and high risk of hemorrhagic transformation with thrombolysis.
About
ASPECTS is a 10-point topographic CT scan score dividing the MCA territory into 10 regions. Each region with early ischemic change subtracts 1 point from 10. Used to identify patients likely to benefit from reperfusion therapy.
When to use
- Acute ischemic stroke with suspected MCA territory involvement
- Before IV tPA or mechanical thrombectomy decision
- Standardizing CT reporting for acute stroke
Formula
Start at 10 points.
Subtract 1 for early ischemic change in each region:
Ganglionic: C (caudate), L (lentiform), IC (internal capsule), I (insular ribbon)
Cortical MCA: M1, M2, M3 (anterior), M4, M5, M6 (posterior)
Score range: 0 (complete MCA infarct) to 10 (normal)
Pearls & pitfalls
- Score starts at 10; subtract 1 for each region with early ischemic change.
- Only applies to MCA territory strokes.
- Assesses hypoattenuation, swelling, or loss of gray-white differentiation.
- Interrater reliability improves with training (experienced neuroradiologists preferred).
- Does NOT include posterior circulation (PCA, vertebrobasilar territory).
Next steps
Score 8-10: Good candidate for reperfusion therapy (low infarct burden). Score 7: Borderline. Score ≤6: High infarct burden — increased hemorrhage risk; individualize decision.
Evidence
Barber et al. Lancet 2000. ASPECTS ≥8 predicted good outcome (mRS 0-1) at 3 months with AUC 0.82.
References
- Barber PA et al. Validity and reliability of a quantitative computed tomography score in predicting outcome of hyperacute stroke before thrombolytic therapy. Lancet. 2000;355(9216):1670-1674. — link
- Hill MD et al. Selection of acute ischemic stroke patients for IV-tPA using ASPECTS. Stroke. 2003;34(2):e43-e45. — link