Technique of upper and lower limb arteries examination

Methodology for examining arteries of the lower limb

The examination always begins with visualization of the pelvic arteries. Several zones have been identified, the examination of which allows differentiation of physiological and pathological changes. Therefore, there is no need to examine the entire lower limb.

Initial examination includes the external iliac artery, common femoral artery, superficial femoral artery, deep femoral artery, popliteal artery, and in the leg, the anterior femoral artery, posterior femoral artery, and, if necessary, the peroneal artery. If abnormalities are detected, all vessels should be examined.

The bifurcation area of the common femoral artery is important as a site prone to the development of atherosclerotic plaques. If the scan reveals occlusion of the superficial femoral artery, the most common location of occlusion of the adductor canal, further attention should be paid to the deep femoral artery, which is an important collateral for the arteries of the leg. It is sometimes difficult to trace the vessel below the knee joint due to its small caliber and when passing through the adductor canal. It is important to analyze the distal vascular segments, since they provide information about the condition of the proximal sections.

Methodology for studying the arteries of the upper limb

Examination of the arteries of the upper limb always begins at the level of the subclavian artery, a common site of occlusion, followed by the axillary and brachial arteries. At 1 cm distal to the elbow, the brachial artery divides into the radial and ulnar arteries. The proximal and distal portions of both vessels are visible with the arm in supination with slight abduction. Note that snapping syndromes in the arm may be missed if abduction is insufficient, as typical poststenotic spectral wave changes are suppressed in this position.

Doppler measurement of peripheral pressure

It is best to use a pocket-sized unidirectional continuous wave Doppler probe with a frequency of 8 or 4 MHz. First, measure the brachial systolic pressure on both sides using the Riva-Rocci cuff. Then, using the Doppler probe, measure the pressure in the ankle area on both sides (during Doppler sonography, the cuff is positioned 10 cm above the ankle). Then, place the Doppler probe behind the ankle to locate the posterior tibial artery, also locate the dorsalis pedis artery and measure at an angle of about 60° to the vessel. Avoid strong pressure on the probe. If the pressure is not within normal limits or is not detectable at all, find the peroneal artery, which is often the most intact vessel and maintains adequate blood supply to the leg.

Results: After measuring systolic pressure, compare the highest values at the ankles and arms on each side to calculate the ankle-brachial index (ABI) and ankle-brachial pressure gradient (ABPG).

Changes in ABI by more than 0.15 or PLP by more than 20 mm Hg during repeated examination allow us to suspect vascular stenosis. This is an indication for CDS. A drop in pressure in the ankle area below 50 mm Hg is considered critical (risk of necrosis).

ABI=BPlod/BPbrachial system. PLGD = ARbrachial syst - ARlod
LPI	Plgd	How to interpret
More than 1.2	Less than -20 mmHg	Suspected Mönckeberg's sclerosis (reduced vascular compressibility)
Greater than or equal to 0.97	From 0 to -20 mm Hg.	Norm
0.7-0.97	From +5 to +20 mm Hg	Vascular stenosis or presence of occlusion with good collaterals, suspicion of OBPA
Less than 0.69	More than 20 mm Hg	Suspected occlusion with poorly developed collaterals, occlusion at several levels

Causes of errors in Doppler pressure measurement

Increased pressure

• Upper body position too high
• Chronic venous insufficiency
• Monkeberg's sclerosis
• Swollen ankles
• Hypertension

Low pressure

• The air in the cuff is deflating too quickly
• Excessive pressure on the sensor
• Insufficient rest period
• Increased pressure in the ankle joint
• Stenosis between cuff and sensor