Difference Between Low Resistance & High Resistance Waveforms On Spectral Doppler Ultrasound USG

Low Resistance: Renal Artery & Internal Carotid Artery
Rounded Systolic Peak: The systolic peak is less sharp and more rounded compared to high resistance waveforms.
Significant flow during diastole
Noticeable end-diastolic velocity, reflecting the sustained blood flow through the diastolic phase.

High Resistance: Common Femoral Artery
Sharp Systolic Peak
Reversed Diastolic Flow due to the resistance in the peripheral vascular bed of the lower limbs.
Triphasic – a rapid systolic peak followed by a brief reversal of flow and then a smaller forward flow or plateau in diastole.

High Resistance: Uterine Artery - Non-Pregnant
Sharp, distinct systolic peak followed by a rapid decrease in blood flow velocity
Absence of flow during early diastole
Low forward flow during the diastolic phase

High Resistance Uterine Artery - 1st Trimester
Lower resistance than in non-pregnant state but has higher resistance than second and third trimesters

Low Resistance Uterine Artery - 2nd Trimester
Further lowered resistance
Increased diastolic flow
Absence of Notching
Decreased sharpness of Systolic Peak
End-Diastolic Flow Presence

свернуть