Alberta Stroke Program Early CT Score — early ischaemic change in the MCA territory, 10 to 0
Mark each MCA region showing early ischaemic change (hypoattenuation or loss of grey–white differentiation) on non-contrast CT.
Caudate (C)
Lentiform nucleus (L)
Internal capsule (IC)
Insular ribbon (I)
M1 — anterior MCA cortex
M2 — MCA cortex lateral to insular ribbon
M3 — posterior MCA cortex
M4 — anterior MCA territory, supraganglionic
M5 — lateral MCA territory, supraganglionic
M6 — posterior MCA territory, supraganglionic
Evidence
Original publication
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 Study Group. Introduced the 10-point topographic CT score; a baseline ASPECTS ≤ 7 predicted worse functional outcome and symptomatic haemorrhage after intravenous thrombolysis.
Lancet, 2000
Open source
Guideline
AHA/ASA acute ischaemic stroke guidelines and the endovascular trials (HERMES pooled analysis) support mechanical thrombectomy for large-vessel occlusion with ASPECTS ≥ 6 in the early window; later trials (SELECT2, ANGEL-ASPECT) extended benefit to selected patients with ASPECTS 3–5. ASPECTS should be read on non-contrast CT by trained observers and correlated with clinical severity and time from onset.
Last reviewed: 2026-09
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