Alberta Stroke Program Early CT Score (ASPECTS)

Using the traditional cutoff (<8 vs ≥8) as a rough estimate for predicting independence may help inform decisions. ASPECTS suggests that early CT changes in stroke may be a harbinger of poor outcomes.

More recent studies have evaluated ASPECTS on the basis of the entire scale, as well as dichotomous (<8 vs ≥8) or trichotomous (0-4, 5-7, and 8-10) divisions, but few robust prospective trials have been conducted (Prakkamakul 2017).

In patients presenting with symptoms concerning for ischemic stroke, the following are generally considered standard practice:

• Neurology consultation.

• Determine onset of stroke symptoms, or time patient last felt or was observed normal.

• Stat head CT to rule out hemorrhagic stroke.

• In appropriate circumstances and in consultation with both neurology and the patient, consider IV thrombolysis for ischemic strokes in patients with no contraindications.

• Always consider stroke mimics in the differential diagnosis, especially in cases with atypical features (age, risk factors, history, physical exam), including:

• Recrudescence of old stroke from metabolic or infectious stress.

• Todd’s paralysis after seizure.

• Complex migraine.

• Pseudoseizure or conversion disorder.

The ASPECTS relies on subtle CT findings and thus requires an experienced radiologist. Its only validated use is as a binary variable (<8 vs ≥8) for general outcome prediction in those eligible for reperfusion therapy.

For patients being considered for intra-arterial tPA administration, ASPECTS may be useful to exclude patients not likely to do well in terms of functional independence (i.e., intra-arterial treatment likely to be futile) (Yoo 2014).