DefinitionThis section has been translated automatically.
The Arterial Resistivity Index (RI) was developed by Léandre Pourcelot. The Index is a sonographic measure of pulsatile blood flow that reflects the vascular resistance of the blood flow caused by the microvascular bed distal to the measurement point. The RI is measured as "peak systolic velocity - end diastolic velocity / peak systolic velocity". The standard value is 0.60.
LiteratureThis section has been translated automatically.
- Pourcelot L. et al. (1965) Effet Doppler et mesure du débit sanguin. CR Acad Sc. Paris 261: 253-256