← Back to CalculatorsHome
Neuroradiology
Demonstration data

ASPECTS

Alberta Stroke Program Early CT Score quantifying early ischaemic change in the MCA territory.

ASPECTS is a 10-point topographic score of early ischaemic change in the middle cerebral artery territory on non-contrast CT. Ten regions each contribute one point; a point is subtracted for each region showing early ischaemic change, so 10 is normal and 0 is diffuse involvement.

🧮 Interactive Calculator

📐 Formula

ASPECTS = 10 − number of affected regions

When to Use

  • Assessing early ischaemic change in acute anterior-circulation stroke.
  • Selecting patients for reperfusion therapy (thrombolysis / thrombectomy).
  • Estimating infarct core burden and haemorrhage risk before treatment.

How It Works

  • Ten MCA regions are assessed: caudate, lentiform, internal capsule, insular ribbon, and M1–M6 cortical regions.
  • Subtract one point for each region with early ischaemic hypoattenuation.
  • The remaining points (0–10) are the ASPECTS.

Interpreting the Result

  • ≥ 8 — small core, favourable for reperfusion with better functional outcome.
  • ≤ 7 — larger established core, worse outcome and higher symptomatic haemorrhage risk.
  • 0 — extensive MCA-territory involvement.

Limitations & Pitfalls

  • Designed for the MCA territory only; not for posterior circulation (use pc-ASPECTS).
  • Early ischaemic change is subtle and reader-dependent, especially at 0–3 hours.
  • Timing of imaging affects the score.

References

  • Barber PA, Demchuk AM, Zhang J, Buchan AM. Validity and reliability of a quantitative computed tomography score in predicting outcome of hyperacute stroke before thrombolytic therapy (ASPECTS). Lancet. 2000;355(9216):1670-1674.
  • Pexman JHW, Barber PA, Hill MD, et al. Use of the Alberta Stroke Program Early CT Score (ASPECTS) for assessing CT scans in patients with acute stroke. AJNR Am J Neuroradiol. 2001;22(8):1534-1542.

⚕️ For clinical decision support only. Always verify calculations and apply clinical judgment.