e-CASES: ASPECTS-scoring on CT-Scan
What is the APSECTS Score
Alberta Stroke Program Early CT score (ASPECTS) is a 10-point quantitative topographic CT scan score
ASPECTS was developed to offer the reliability and utility of a standard CT examination with a reproducible grading system to assess early ischemic changes on pretreatment CT studies in patients with acute ischemic stroke of the anterior circulation.
How to compute ASPECTS
ASPECTS is determined from evaluation of two standardized regions of the MCA territory: the basal ganglia level, where the thalamus, basal ganglia, and caudate are visible, and the supraganglionic level, which includes the corona radiata and centrum semiovale
All cuts with basal ganglionic or supraganglionic structures visible are required to determine if an area is involved. The abnormality should be visible on at least two consecutive cuts to ensure that it is truly abnormal rather than a volume averaging effect
To compute the ASPECTS, 1 point is subtracted from 10 for any evidence of early ischemic change for each of the defined regions.
Axial NCCT images showing the MCA territory regions as defined by ASPECTS :
I- Insular ribbon,
IC- Internal Capsule,
L- Lentiform nucleus,
M1- Anterior MCA cortex,
M2- MCA cortex lateral to the insular ribbon,
M3- Posterior MCA cortex,
M4, M5, M6 are the anterior, lateral and posterior MCA territories immediately superior to M1, M2 and M3, rostral to basalganglia.
Subcortical structures are allotted 3 points (C, L, and IC).MCA cortex is allotted 7 points (insular cortex, M1, M2, M3, M4, M5and M6
A normal CT scan receives ASPECTS of 10 points.
A score of 0 indicates diffuse involvement throughout the MCA territory
Pexman JH, Barber PA, Hill MD, Sevick RJ, Demchuk AM, Hudon ME, Hu WY, Buchan AM.
AJNR Am J Neuroradiol. 2001 Sep;22(8):1534-42.