Arterial ultrasound

Head and neck vessel examination

The main targets of ultrasound examination at the neck level are the carotid, vertebral, and subclavian arteries, as well as the jugular veins. Visualizing intracranial vessels is technically considerably more challenging.

Assessment of the carotid artery basin is of particular clinical importance:

• Common carotid artery (CCA)
• External carotid artery (ECA)
• Internal carotid artery (ICA)

The highest diagnostic efficacy of the method is observed during targeted scanning of the CCA bifurcation zone and the ICA origin. This specific anatomical region is the most vulnerable to atherosclerotic lesions and plaque formation.

If a specialist detects a severe degree of internal carotid artery narrowing, the question of surgical treatment arises. The main surgical intervention methods include carotid endarterectomy and vessel stenting.

Patients who have undergone such surgery require a strict follow-up protocol for the prevention of recurrent stroke. Control duplex examinations are scheduled at 3 and 6 months after the intervention, and are subsequently performed once a year for life.

Transcranial Doppler (TCD)

Transcranial Doppler is used to assess the status of intracranial vessels.

The main objectives of this method:

1. Detection of hemodynamically significant stenoses. A narrowing of the lumen by more than 70% of the original vessel diameter is considered significant.
2. Diagnosis of complete blockage (occlusion) of an intracranial artery.
3. Determination of the nature and assessment of the adequacy of collateral circulation, which compensates for blood flow deficits in occlusive lesions of the cerebral vascular bed.

Assessment of lower extremity and renal arteries

Duplex scanning is the method of choice for diagnosing lower extremity arterial patency, as it is completely non-invasive compared to other imaging modalities (such as MR or CT angiography).

When renal artery patency impairment (stenosis) is suspected in patients with chronic kidney disease (CKD), a strict two-stage diagnostic algorithm with the highest level of evidence is applied.

• Initial diagnostics: duplex scanning of the renal arteries is performed. The method has a high diagnostic value, which is comparable to the "gold standard" — angiography.
• Confirmatory diagnostics: if the ultrasound results are inconclusive or there are clear technical limitations (e.g., severe patient obesity or marked meteorism that hinders the ultrasound beam), the second stage is initiated. In such cases, despite the higher cost, it is necessary to use renal CT or contrast-enhanced renal MRI to obtain an accurate conclusion.

Ultrasound signs of stenosis

To accurately establish the diagnosis and determine the degree of narrowing, specialists rely on two main modes of ultrasound duplex scanning:

• Color Doppler mapping (CDM): makes it possible to visually assess the anatomical area of significant vessel lumen narrowing. A color-filling defect is clearly identified in this area on the monitor.
• Spectral Doppler ultrasound: allows for the evaluation of hemodynamic parameters. The main ultrasound criterion for stenosis (e.g., in the ICA basin) is the recording of a significant increase in blood flow velocity directly at the site of the narrowing.

Class and exam questions

What else to study on this topic

• Medical service nomenclature codes for brachiocephalic artery ultrasound
• Surgical tactics (endarterectomy and stenting) in severe ICA stenosis
• Evaluation of collateral circulation in intracranial vessel occlusions
• Levels of conviction and reliability of evidence (LCE and LRE) in ultrasound protocols

Prepared by WhiteCoat Pro faculty in accordance with the medical school curriculum. For educational purposes only.