Today. I review, link to, and excerpt from Radiopaedia‘s “Alberta stroke programme early CT score (ASPECTS)”.* Last revised by Henry Knipe on 2 Mar 2026.
*Citation:Sair H, Khalighinejad P, Hacking C, et al. Alberta stroke programme early CT score (ASPECTS). Reference article, Radiopaedia.org (Accessed on 13 Jul 2026) https://doi.org/10.53347/rID-4936
DOI:https://doi.org/10.53347/rID-4936
Permalink:https://radiopaedia.org/articles/alberta-stroke-programme-early-ct-score-aspects
rID:Article (rID 4936, “Alberta stroke programme early CT score (ASPECTS)”)
All that follows is from the above resource.
The Alberta stroke program early CT score (ASPECTS) 1 is a 10-point quantitative topographic CT score used for patients with middle cerebral artery (MCA) stroke. It has also been adjusted for the posterior circulation (see below).
Usage
An ASPECTS score ≤7 predicts a worse functional outcome at 3 months as well as symptomatic hemorrhage. According to the study by Aviv et al., patients with an ASPECTS score <8 treated with thrombolysis did not have a good clinical outcome 3.
Classification
Segmental estimation of the middle cerebral artery (MCA) vascular territory is made, and 1 point is deducted from the initial score of 10 for every region involved:
- caudate
- putamen
- internal capsule
- insular cortex
- M1: “anterior MCA cortex,” corresponding to the frontal operculum
- M2: “MCA cortex lateral to insular ribbon” corresponding to the anterior temporal lobe
- M3: “posterior MCA cortex” corresponding to the posterior temporal lobe
- M4: “anterior MCA territory immediately superior to M1”
- M5: “lateral MCA territory immediately superior to M2”
- M6: “posterior MCA territory immediately superior to M3”
Important points:
- the initial paper 1 specifically referred to the internal capsule only involving the posterior limb, however, subsequent articles indicate any portion of the internal capsule may be included
- M1 to M3 are at the level of the basal ganglia
- M4 to M6 are at the level of the ventricles immediately above the basal ganglia
- M1 to M4 are not to be confused with the anatomic segments of the middle cerebral artery
Posterior circulation
Variations of the ASPECT scoring system have been described for use in the posterior circulation and referred to as pc-ASPECTS 5.
As is the case for the anterior circulation, the pc-ASPECTS is a 10 point scale, where points are lost for each region affected. Unlike ASPECTS, the pons and the midbrain are worth 2 points each (regardless of whether or not the changes are bilateral; any involvement of the pons, for example, deducted 2 points).
- thalami (1 point each)
- occipital lobes (1 point each)
- midbrain (2 points)
- pons (2 points)
- cerebellar hemispheres (1 point each)
See also
External links
References
- 1. Barber P, Demchuk A, Zhang J, Buchan A. Validity and Reliability of a Quantitative Computed Tomography Score in Predicting Outcome of Hyperacute Stroke Before Thrombolytic Therapy. ASPECTS Study Group. Alberta Stroke Programme Early CT Score. Lancet. 2000;355(9216):1670-4. doi:10.1016/s0140-6736(00)02237-6 – Pubmed
- 2. Pexman J, Barber P, Hill M 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):1534-42. PMC7974585 – Pubmed
- 3. Aviv R, Mandelcorn J, Chakraborty S et al. Alberta Stroke Program Early CT Scoring of CT Perfusion in Early Stroke Visualization and Assessment. AJNR Am J Neuroradiol. 2007;28(10):1975-80. doi:10.3174/ajnr.A0689 – Pubmed
- 4. Puetz V, Dzialowski I, Hill M, Demchuk A. The Alberta Stroke Program Early CT Score in Clinical Practice: What Have We Learned? Int J Stroke. 2009;4(5):354-64. doi:10.1111/j.1747-4949.2009.00337.x – Pubmed
- 5. Puetz V, Sylaja P, Coutts S et al. Extent of Hypoattenuation on CT Angiography Source Images Predicts Functional Outcome in Patients with Basilar Artery Occlusion. Stroke. 2008;39(9):2485-90. doi:10.1161/STROKEAHA.107.511162 – Pubmed
Incoming Links
Articles:Cases:
- Extensive MCA infarct
- Left MCA territory infarct with dense MCA sign
- Middle cerebral artery infarction
- Middle cerebral artery territory acute infarction
- Post-thrombolysis contrast staining
- Bilateral ACA infarction due to azygos ACA embolism
- Left MCA bifurcation infarct
- Acute middle cerebral artery infarction
- Normal code stroke
- Posterior circulation – Acute stroke prognosis early CT score (pc-ASPECTS) illustration
- MCA – Alberta stroke program early CT score (ASPECTS) illustration
- MCA ischemic stroke – added value of CTA source image ASPECTS
- MCA ischemic stroke – added value of CTA source image ASPECTS
- Acute right MCA M1 occlusion
- Acute right MCA M1 occlusion
- Ischaemic stroke
- Proximal right MCA M1 segment embolic occlusion
- Middle cerebral artery territory in ASPECTS study
- PCA infarct
- CT perfusion – occipital core infarct
Multiple choice questions:Related articles: Stroke and intracranial haemorrhage
- stroke and intracranial hemorrhage
- general articles[+]
- ischemic stroke
- general discussions[+]
- scoring and classification systems
- Alberta stroke program early CT score (ASPECTS)
- ASCOD classification
- Canadian Neurological Scale
- CISS classification
- Heidelberg bleeding classification
- NIH Stroke Scale
- Mathew stroke scale
- modified Rankin scale
- Orgogozo Stroke Scale
- Scandinavian Stroke Scale
- thrombolysis in cerebral infarction (TICI) scale[+]
- TOAST classification
- collateral vessel scores[+]
- signs[+]
- by region[+]
- by vascular territory[+]
- by vessel size[+]
- treatment options[+]
- complications[+]
- intracranial hemorrhage[+]
