Calculate and report the exact 0-10 score plus involved regions and modality. The legacy RadCommons outcome bands are interpretive outputs; current EVT selection requires the additional variables encoded in EVT_2026_context.
{
"applicability": {
"use_for": "Early ischemic change in the affected middle cerebral artery territory on noncontrast CT in acute anterior-circulation ischemic stroke.",
"interpret_with": [
"affected_hemisphere",
"vessel_occlusion_site",
"time_from_onset_or_last_known_well",
"NIHSS",
"prestroke_mRS",
"age",
"mass_effect",
"other_imaging_and_clinical_criteria"
],
"do_not_substitute": [
"PC_ASPECTS_for_posterior_circulation",
"DWI_ASPECTS_without_naming_the_modality",
"volumetric_core_measurement"
]
},
"starting_score": 10,
"operation": "Subtract one point for each defined region with early ischemic change; minimum 0 and maximum 10.",
"early_ischemic_change": [
"focal_brain_swelling",
"parenchymal_hypoattenuation"
],
"feature_groups": [
{
"id": "deep_structures",
"points_each_if_involved": -1,
"regions": [
{
"code": "C",
"name": "caudate"
},
{
"code": "L",
"name": "lentiform_nucleus"
},
{
"code": "IC",
"name": "internal_capsule"
}
]
},
{
"id": "mca_cortical_regions",
"points_each_if_involved": -1,
"regions": [
{
"code": "I",
"name": "insular_ribbon"
},
{
"code": "M1",
"name": "anterior_MCA_cortex_frontal_operculum"
},
{
"code": "M2",
"name": "MCA_cortex_lateral_to_insular_ribbon_anterior_temporal_lobe"
},
{
"code": "M3",
"name": "posterior_MCA_cortex_posterior_temporal_lobe"
},
{
"code": "M4",
"name": "anterior_MCA_territory_immediately_superior_to_M1"
},
{
"code": "M5",
"name": "lateral_MCA_territory_immediately_superior_to_M2"
},
{
"code": "M6",
"name": "posterior_MCA_territory_immediately_superior_to_M3"
}
]
}
],
"levels": {
"ganglionic": [
"C",
"L",
"IC",
"I",
"M1",
"M2",
"M3"
],
"supraganglionic": [
"M4",
"M5",
"M6"
]
},
"score_map": [
{
"score": 10,
"outcome_code": "10",
"interpretation": "No early ischemic change in the ten assessed MCA regions."
},
{
"score": "6-9",
"outcome_code": ">=6",
"interpretation": "Limited regional early ischemic change; legacy RadCommons band excludes the separately represented exact score 10."
},
{
"score": "0-5",
"outcome_code": "<6",
"interpretation": "Larger burden of regional early ischemic change; management differs between scores 3-5 and 0-2."
}
],
"EVT_2026_context": [
{
"time_window": "0-6_hours",
"ASPECTS": "3-10",
"other_required_features": [
"anterior_circulation_ICA_or_M1_LVO",
"NIHSS>=6",
"prestroke_mRS_0-1"
],
"recommendation": "EVT_recommended"
},
{
"time_window": "6-24_hours",
"ASPECTS": "6-10",
"other_required_features": [
"anterior_circulation_ICA_or_M1_LVO",
"NIHSS>=6",
"prestroke_mRS_0-1"
],
"recommendation": "EVT_recommended"
},
{
"time_window": "6-24_hours",
"ASPECTS": "3-5",
"other_required_features": [
"selected_patient",
"age<80",
"anterior_circulation_ICA_or_M1_LVO",
"NIHSS>=6",
"prestroke_mRS_0-1",
"no_significant_mass_effect"
],
"recommendation": "EVT_recommended"
},
{
"time_window": "0-6_hours",
"ASPECTS": "0-2",
"other_required_features": [
"selected_patient",
"age<80",
"anterior_circulation_ICA_or_M1_LVO",
"NIHSS>=6",
"prestroke_mRS_0-1",
"no_significant_mass_effect"
],
"recommendation": "EVT_reasonable"
}
],
"safety_rule": "ASPECTS is one imaging input, not a standalone treatment decision. Never deny or mandate reperfusion therapy from the score alone.",
"source_locator": "Barber et al., Lancet 2000, Methods pp 1671-1672 and Fig 1 for score operation and ten regions; AHA/ASA 2026 AIS Guideline, section 4.7.2 recommendations 1-4 for EVT selection."
}