| % Stenosis | Peak Velocity | Velocity Ratio |
|---|---|---|
| Normal | <150 cm/s | <2 |
| 30-49% | 150-200 cm/s | 1.5:1-2:1 |
| 50-75% | 200-400 cm/s | 2:1-4:1 |
| >75% | >400 cm/s | >4:1 |
| Occlusion | No flow | null |
Crossman DV, Ellison, JE, et al.
Comparison of contrast angiography to arterial mapping with color flow duplex imaging in the lower extremities.
J Vasc Surg 1989; 10:522-32