The Alberta stroke programme early CT score (ASPECTS) 1 is a 10-point quantitative topographic CT scan score used in patients with middle cerebral artery stroke. It has also been adapted for the posterior circulation (see below).
Segmental assessment of the MCA vascular territory is made and 1 point is deducted from the initial score of 10 for every region involved:
- internal capsule
- insular cortex
- M1: "anterior MCA cortex," corresponding to frontal operculum
- M2: "MCA cortex lateral to insular ribbon" corresponding to anterior temporal lobe
- M3: "posterior MCA cortex" corresponding to 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"
- 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 is at the level of the ventricles immediately above the basal ganglia
An ASPECTS score less than or equal to 7 predicts a worse functional outcome at 3 months as well as symptomatic hemorrhage.
According to the study performed by R. I. Aviv et al., patients with ASPECTS score less than 8 treated with thrombolysis did not have a good clinical outcome 3.
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)
- 1. Barber PA, Demchuk AM, Zhang J et-al. 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. Pubmed citation
- 2. Pexman JH, 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): 1534-42. Pubmed citation
- 3. Aviv RI, 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 citation
- 4. Puetz V, Dzialowski I, Hill MD et-al. 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 citation
- 5. Puetz V, Sylaja PN, Coutts SB, Hill MD, Dzialowski I, Mueller P, Becker U, Urban G, O'Reilly C, Barber PA, Sharma P, Goyal M, Gahn G, von Kummer R, Demchuk AM. Extent of hypoattenuation on CT angiography source images predicts functional outcome in patients with basilar artery occlusion. (2008) Stroke. 39 (9): 2485-90. doi:10.1161/STROKEAHA.107.511162 - Pubmed