ICD-10-PCS Billable Code

B348ZZ3

Ultrasonography Internal Carotid Arteries, Bilateral to Intravascular with None, None Approach

Procedural Specifications

Clinical Axis Detail Definition
SectionB Imaging
Body System3 Upper Arteries
Operation4 Ultrasonography
Body Part8 Internal Carotid Arteries, Bilateral
ApproachZ None
DeviceZ None
Qualifier3 Intravascular

Operation Definition

Real time display of images of anatomy or flow information developed from the capture of reflected and attenuated high frequency sound waves

Procedure Overview

This family describes ultrasound imaging of the arteries in the neck, chest, and arms, most commonly the carotid and subclavian vessels. A handheld probe sends high-frequency sound waves into the tissue and captures the echoes that bounce back, building a live picture of the vessel and, with Doppler technique, the direction and speed of blood moving through it.

It is a common first step in evaluating carotid artery disease, stroke risk, or suspected blood clots in the arm, largely because it is quick, radiation-free, and can be performed at the bedside. Vascular surgeons and neurologists also use it to monitor known narrowing over time or to check blood flow before and after a procedure on these vessels.

Anatomy & Axis Detail

Internal Carotid Arteries, Bilateral

Imaging both internal carotid arteries in one session lets the sonographer compare velocity measurements and waveform patterns side to side, which improves detection of asymmetric stenosis and helps confirm that an elevated velocity on one side reflects true focal narrowing rather than a globally altered flow state, such as contralateral occlusion driving compensatory high flow. Bilateral internal carotid assessment is standard whenever stroke risk is being evaluated broadly rather than in response to a lateralized symptom, and it is also used for baseline screening in patients with known atherosclerotic disease elsewhere. Because velocity-based grading criteria assume a comparably normal contralateral vessel, having both sides imaged together supports more reliable staging of stenosis severity.

Qualifier: Intravascular

This qualifier specifies that an imaging study is performed intravascularly, with the imaging device positioned inside a blood vessel, as in intravascular ultrasound. It differs from the transesophageal qualifier, which places the imaging probe in the esophagus rather than within the vascular system itself.

Coding & Documentation

A code from this family requires documentation naming the specific upper artery examined and confirming the study was performed with ultrasound, often noted as a duplex or Doppler scan. Coders should distinguish a diagnostic ultrasound exam from an ultrasound used only to guide a needle or catheter placement, since guidance-only use is not coded under this imaging root operation. A common mistake is coding bilateral carotid studies as a single unspecified vessel rather than capturing that both sides were interrogated, and overlooking whether the report supports a qualifier like intravascular imaging versus standard external probe imaging.

Commonly Confused With

The main point of confusion is with MRI or CT angiography of the same arteries, which are differentiated purely by the modality used to generate the image rather than the vessel studied. It also overlaps conceptually with ultrasonography performed during an interventional procedure for guidance, which is not separately coded as diagnostic imaging. Coders should also separate arterial ultrasound from venous studies of the neck and arm, since veins fall under a different body system despite similar technique and equipment.