Lower extremity arterial Doppler ultrasound: how to structure the report in peripheral artery disease

Peripheral artery disease (PAD) is one of the most underdiagnosed vascular conditions in clinical practice. Many patients reach the office with intermittent claudication, rest pain or trophic lesions at an advanced stage, when early diagnosis could have completely changed the course of the disease. Lower extremity arterial Doppler ultrasound is the reference noninvasive exam for this evaluation, as long as the report is complete, standardized and clinically useful to the referring physician.

In vascular practice, it is common to receive vague requests such as “Lower extremity arterial Doppler: rule out PAD” and to return reports that sometimes describe too many plaques, sometimes too few velocities, and sometimes lack an objective conclusion about the degree of involvement. The result is the vascular specialist ordering a CT angiogram to confirm what the ultrasound should already have answered. In this post, we show how to structure the lower extremity arterial Doppler report so that it truly guides management.

When the exam is indicated

The main indications for lower extremity arterial Doppler include intermittent claudication, ischemic rest pain, trophic lesions or ulcers that are slow to heal, absent or diminished peripheral pulses, an abnormal ankle-brachial index (ABI), preoperative planning for revascularization, and follow-up of bypass grafts or angioplasty with stenting. In diabetic patients, smokers and patients with chronic kidney disease, it plays an even more important role because of the increased risk of arterial calcification and silent ischemia.

Recommended report structure

A well-structured arterial Doppler report follows an anatomical sequence from proximal to distal and covers three components in each segment assessed: B-mode, color Doppler and spectral Doppler. The classic segments to document are: distal abdominal aorta, common, external and internal iliac arteries, common femoral, deep femoral, superficial femoral in the three thirds, popliteal, tibioperoneal trunk, anterior tibial, posterior tibial and peroneal arteries. Whenever there is a bypass or stent, that segment should be reported separately.

What to describe in B-mode

In B-mode, describe the presence and extent of atherosclerotic plaques, their composition (calcified, fibrous, lipid-rich, mixed), the presence of ulceration or irregularity, and the degree of wall calcification (information that is especially useful in diabetic patients, in whom medial calcification can compromise the ABI measurement). Measure the arterial diameter whenever there is focal dilation. Popliteal artery aneurysms, for example, should always be sought bilaterally, because they are often asymptomatic and carry a risk of acute thrombosis.

Color and spectral Doppler: what to measure

Color Doppler guides the identification of stenoses, occlusions and turbulent flow (aliasing). Spectral Doppler, in turn, is where the disease is quantified. In each segment, record the peak systolic velocity (PSV), the waveform morphology (triphasic, biphasic or monophasic) and, when a stenosis is suspected, the pre-stenotic to intrastenotic PSV ratio (Vr).

Spectral morphology is an extremely sensitive clinical marker: loss of the usual triphasic pattern to a biphasic or monophasic one indicates proximal obstructive disease, even in the absence of a hemodynamically significant stenosis in the segment being assessed.

Stenosis grading criteria

The criteria most used in practice are based on PSV and the velocity ratio:

• No significant stenosis: normal PSV for the segment, triphasic spectrum, Vr < 2.0.
• 50 to 75% stenosis: intrastenotic PSV ≥ 200 cm/s, Vr ≥ 2.0, spectrum with spectral broadening.
• 75 to 99% stenosis: intrastenotic PSV ≥ 400 cm/s, Vr ≥ 4.0, dampened distal flow (tardus-parvus).
• Occlusion: absence of flow on color and spectral Doppler in the segment, with possible reconstitution by distal collaterals.

Keep in mind that these ranges vary slightly depending on the literature adopted and the segment assessed. What matters is to state clearly in the report which criterion is being applied.

Findings that must not be missing from the conclusion

The conclusion of the report should answer objectively what was requested. Include: the presence and location of the most relevant stenoses or occlusions, the side involved, the estimated hemodynamic grade, the presence of aneurysms (especially popliteal), patency of grafts or stents when applicable, and a guiding clinical classification when possible, such as the Rutherford classification or the Fontaine classification, which helps the vascular specialist decide between clinical, endovascular or surgical management.

Common mistakes that undermine the report

A few recurring slips undermine the clinical usefulness of the exam: describing plaques without quantifying the stenosis; omitting spectral morphology in distal segments; not comparing pre-stenotic and intrastenotic PSV; ignoring the search for popliteal aneurysm; and, perhaps most frequently, delivering a generic conclusion such as “mild diffuse atheromatosis” without saying where, to what degree and with what hemodynamic impact. Standardizing the report structure is what prevents these lapses.

How Laudário helps structure lower extremity arterial Doppler

Laudário was designed precisely to solve these day-to-day bottlenecks for the vascular sonologist. For lower extremity arterial Doppler and other vascular exams, it offers:

• Ready-made, editable templates for lower extremity arterial Doppler, with the full anatomical sequence from the distal aorta to the tibial arteries, so you never forget a segment.
• Preformatted fields for PSV, Vr and spectral morphology in each segment, ensuring that the report follows objective grading criteria.
• Customizable phrases and conclusions, allowing each physician to keep their own style within a standardized structure, including the Rutherford/Fontaine classification when applicable.
• A library of more than 58 ultrasound templates organized by area (abdomen, pelvis, urology, musculoskeletal, obstetrics, breast, thyroid, vascular and special exams), including lower extremity venous Doppler, carotid Doppler and arterial Doppler.
• Digital signature, validation QR Code and an online version of the report, giving the patient and the referring physician a professional, traceable and standardized document.
• Integrated AI that assists in writing and reviewing the report, reducing rework and time per exam.

In practice, the gain is twofold: the sonologist produces more reports per shift without losing quality, and the vascular specialist receives an objective document, with measurable criteria and a clinically useful conclusion. This is standardization serving medicine, not the other way around.

Want to test how Laudário can transform your vascular reporting routine? Try it free for 15 days and see the difference on your very next shift.