NASCET Carotid Stenosis
NASCET carotid stenosis (NEJM 1991): % stenosis = (1 - narrowest residual lumen / normal distal ICA diameter) x 100; >= 70% is severe.
Open the calculator → Runs in your browser. Data leaves only if you deliberately send a problem report from the interactive tool.
Example
- Narrowest residual lumen
- 3 mm
- Normal distal ICA diameter
- 8 mm
Result: NASCET carotid stenosis 62.5% — moderate (50-69%).
The tool opens with these values already filled in. Replace them with your own.
What the result means
- < 50%
- Mild.
- 50-69%
- Moderate.
- >= 70%
- Severe (surgical threshold for symptomatic disease; (1 - narrowest / distal) x 100). A measurement, not a diagnosis.
What you enter
- Narrowest residual lumen
- Normal distal ICA diameter
How this is calculated
North American Symptomatic Carotid Endarterectomy Trial Collaborators. Beneficial effect of carotid endarterectomy in symptomatic patients with high-grade carotid stenosis. N Engl J Med. 1991;325(7):445-453. Read the source ↗
A reference and educational tool. Not medical, legal, or financial advice, and not a substitute for clinician judgment.