Minimum training requirement in ultrasound imaging of peripheral arterial disease

To demonstrate the minimum training requirement when performing ultrasound of peripheral arterial disease.

Prospective and blinded comparative study.

100 limbs in 100 consecutive patients suffering from peripheral arterial disease, 74% suffering critical limb ischemia, were enrolled during a 9 months period.

One physician with limited ultrasound experience performed all the ultrasound examinations of the arteries of the most symptomatic limb. Before enrolling any patients 15 duplex ultrasound examinations were performed supervised by an experienced vascular technologist. All patients had a digital subtraction arteriography performed by an experienced vascular radiologist, unaware of the ultrasound result.

The number of insufficiently insonated segments (non-diagnostic segments) was significantly reduced during the study; from 9% among the initial 50 limbs to 2% among the last 50 limbs (P<0.0001). This improvement was evident only in the infragenicular segments, as the performance within the supragenicular segments was good from the beginning. There was no change in the agreement between ultrasound and arteriography from the initial 50 patients (overall Kappa=0.66, (95%-CI: 0.60-0.72); supragenicular Kappa=0.73 (95%-CI: 0.64-0.82); infragenicular Kappa=0.61 (95%-CI: 0.54-0.69)) to the last 50 patients (overall Kappa=0.66 (95%-CI: 0.60-0.72), supragenicular Kappa=0.67 (95%-CI: 0.57-0.76); infragenicular Kappa=0.66 (95%-CI: 0.58-0.73)).

The minimum training requirement in ultrasound imaging of peripheral arterial disease appears to be less than 50 ultrasound examinations (probably only 15 examinations) for the supragenicular segments and 100 examinations for the infragenicular segments.