ADDONS / SCALES
ASPECTS
Alberta Stroke Program Early CT Score
Created 22/03/2021, last revision 18/01/2023
- the Alberta Stroke Program Early CT Score (ASPECTS) is used to standardize and increase the reliability of early signs of ischemia detection
- ASPECTS can be assessed on:
- non-contrast CT (NCCT) – width/level adjustment can be helpful
- CT perfusion (CTP) [Aviv, 2007]
- CTA source images (CTA-SI) [Puetz, 2009]
- non-contrast CT (NCCT) – width/level adjustment can be helpful
- ASPECTS primarily evaluates the MCA territory
- PC-ASPECTS was designed to evaluate changes in the posterior circulation
- there are commercial programs available for the automatic evaluation of ASPECTS (e.g., BRAINOMIX)
MCA territory
- a 10-point quantitative CT scan score used for patients with stroke in MCA territory
- 10 points are normal; 1 point is subtracted from the initial score of 10 for each region with early signs of ischemia
- C – caudate nucleus
- L – lentiform nucleus
- IC – internal capsule (any portion)
- I – the insular cortex
- M1-3 are at the level of the basal ganglia
- 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
- M4-5 are above the basal ganglia at the level of the ventricles
- M4 – anterior MCA territory immediately superior to M1
- M5 – lateral MCA territory immediately superior to M2
- M6 – posterior MCA territory immediately superior to M3
- ASPECTS is a valuable technique for the evaluation of the prognosis in acute ischemic stroke (thresholds are slightly different for NCCT a CTP)
- patients with high ASPECTS values are more likely to have favorable outcomes
- an NCCT ASPECTS score of ≤ 7 predicts a worse functional outcome at three months [Esmael, 2021]
- patients with CTP ASPECTS score of < 8 treated with thrombolysis mainly did not achieve a good clinical outcome [Aviv, 2007]
Posterior circulation
PC-ASPECTS (The posterior circulation Acute Stroke Prognosis Early CT score)
- normal brain scores 10 points; points are subtracted for each affected region
- thalami (1 point each)
- occipital lobes (1 point each)
- midbrain (2 points – uni- and bilateral)
- pons (2 points – uni- and bilateral)
- cerebellar hemispheres (1 point each)
- pc-ASPECTS < 8 points ⇒ poor prognosis [Puetz, 2009]