Sievering Clinic

Competence Centre for Minimally Invasive Medical Services

Diagnosis

Non-invasive Diagnosis Methods

Doppler Auscultation

The physical examination as described thus far cannot differentiate dilated veins of normal function from true varicosities that carry venous blood in a retrograde direction. Doppler examination is an adjunct to the physical examination that can directly show whether flow in a suspect vein is antegrade, retrograde, or to-and-fro.

When used as part of the physical examination, a Doppler transducer is positioned along the axis of a vein with the probe at an angle of 45u00b0 to the skin. Gentle tapping on the underlying vessel produces a strong Doppler signal and confirms the correct positioning of the transducer.

An augmentation manoeuvre is performed by compressing and then releasing the underlying veins and muscles below the level of the probe. Compression causes forward flow in the direction of the valves. Release of compression causes backward flow through incompetent valves, but no Doppler signal is noted if the valves are competent and the blood cannot flow backwards.
These compression-decompression manoeuvres are repeated while gradually ascending the limb to a level where the reflux can no longer be appreciated.

Each superficially visible or palpable is investigated in this way. If no visible or palpable dilated varicose veins exist, the presence or absence of retrograde flow is documented at the top, middle, and bottom of long and short saphenous veins on each leg.

Doppler flow assessment adds a great deal of information to the physical examination findings, but patients with significant varicosities should also be evaluated by duplex ultrasonography, which combines Doppler flow detection with 2-dimensional ultrasound imaging.