Non-Invasive Vascular Screening Procedures

Lower Extremities Arterial Screening
This is a quick and painless examination performed to detect and localize peripheral vascular disease. This procedure is used to evaluate patients' symptoms of claudication, non-healing ulcers and leg pain.  This study can be ordered with or without exercise on the tread mill.

Prep  no prep needed

FAQ

1. How long does the procedure take?

   • approximately 1 hour

2. Will I have to do anything?

   • You may be asked to walk on a treadmill for a short period of time.

3. What can be done if I have peripheral vascular disease?

   • Your Physician and the Radiologist will review your case and make recommendations such as exercise, medication, special procedures, or surgery.

vascular ultrasound monitoring

The goal of evaluation is to establish whether obstruction or significant narrowing is present in the major arteries to the leg. In syndromes such as claudication, the characteristic nature of symptoms may be diagnostic, and testing serves to confirm, localize, and determine severity of disease. In other settings, for example resistant infection in the foot, we seek to determine if
vascular disease is present, and if so, where and how severe.

The methods are safe and effective, both as a screening mechanism and to guide treatment.

When surgical bypass or angioplasty is considered, additional testing in the form of invasive angiography is usually required.

Basic principles:
1.) Disease localization:
In pressure and waveform analysis, disease is localized within one of 5 segments in the extremity. Here the pressure cuff or CW Doppler probe is applied at 4 or 5 standard levels. The vascular stenosis causes pressure and waveform changes which are propagated distally (downstream) to be detected at the next measurement level. The measurement sites themselves often span common disease levels and lead to uncertainty. The methods are sensitive to the presence of disease, but precise localization requires angiography or duplex doppler. Color flow imaging and quantitative Doppler velocity on the other hand precisely identify both site and severity of disease and can potentially provide all needed information to plan treatment. Practically however, they are difficult, time consuming, and some "blind spots" may occur which reduce sensitivity. Angiography may still be required for localization.
2.) Sensitivity:
These examinations are easiest to perform in the supine (lying on your back with your face upward) resting patient. Moderate and severe disease which causes rest pain, non-healing sores, or severe claudication are usually evident on resting studies. Mild claudication noted at high exertion levels usually require exercise or hyperemic testing for detection. Accuracy regarding severity and location is reduced with mild degrees of stenosis. Patients with calcified vessels (particularly diabetics) can give false normal results because their vessels are resistant to compression by pressure cuffs. Usually the toe vessels are unaffected and can provide valid pressure, but care is required in interpreting results.
3.) Patient tolerance:
For resting studies no patient effort is required, however segmental pressure testing requires tight pressure cuffs which are not tolerated by tender patients. If the ankle or toe can be compressed without pain, it is usually possible to use these distal pressures to screen for disease, but localization may suffer.

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