ICD-10-PCS Billable Code

B317110

Fluoroscopy Internal Carotid Artery, Left to Intraoperative with Laser, Low Osmolar Approach

Procedural Specifications

Clinical Axis Detail Definition
SectionB Imaging
Body System3 Upper Arteries
Operation1 Fluoroscopy
Body Part7 Internal Carotid Artery, Left
Approach1 Low Osmolar
Device1 Laser
Qualifier0 Intraoperative

Operation Definition

Single plane or bi-plane real time display of an image developed from the capture of external ionizing radiation on a fluorescent screen. The image may also be stored by either digital or analog means

Procedure Overview

Fluoroscopy of the upper arteries is a real-time x-ray technique in which contrast dye injected into the bloodstream is tracked continuously on a screen as it travels through the subclavian, axillary, brachial, or other arm arteries. This moving picture, often called an arteriogram, lets a physician see narrowing, blockage, aneurysm, or abnormal connections between vessels as blood actually flows past them, which a single static image cannot show.

It is typically performed when a patient has symptoms suggesting reduced blood flow to the arm, such as pain, coolness, or weak pulses, or to plan and guide a subsequent procedure like angioplasty or stent placement. A catheter is usually threaded through a blood vessel to the area of interest, contrast is injected, and the radiologist watches the images live, sometimes storing them digitally for later review.

Anatomy & Axis Detail

Internal Carotid Artery, Left

The left internal carotid artery ascends from the carotid bifurcation without giving off cervical branches, coursing toward the skull base to become a principal source of blood flow to the anterior and middle cerebral circulation on that side. Fluoroscopic evaluation focuses on the bulb and proximal cervical segment where atherosclerotic plaque most commonly develops, as well as assessment for dissection, which can present with a tapering or double-lumen appearance during contrast injection. Because stenosis in this vessel carries direct stroke risk, the study is often obtained in patients with prior transient ischemic symptoms or an abnormal carotid duplex ultrasound requiring more precise catheter-based characterization. Findings from this run, including percent stenosis and plaque morphology, directly inform whether left-sided carotid revascularization is warranted and how it should be approached.

Contrast: Low Osmolar

Low Osmolar denotes use of a low-osmolar iodinated contrast agent during an imaging study, the class most commonly used in modern radiographic and CT imaging because it better approximates the osmolality of blood and carries a lower risk of reaction than High Osmolar media. This value distinguishes studies performed with this now-standard contrast type from those using older high-osmolar agents or no contrast at all.

Qualifier: Laser

Laser as an imaging qualifier indicates that laser-based technology was integral to acquiring the image, as seen in certain ophthalmic or optical imaging modalities. It reflects the light source or scanning mechanism rather than a chemical contrast agent. It is distinguished from Intravascular Optical Coherence, which uses laser light specifically within a vessel via catheter-based optical coherence tomography.

Qualifier: Intraoperative

This qualifier indicates that an imaging study is performed intraoperatively, meaning the images are obtained during an ongoing surgical procedure rather than as a separate diagnostic encounter. It distinguishes real-time surgical imaging from routine preoperative or postoperative studies, which carry the None qualifier instead.

Coding & Documentation

Documentation must confirm that contrast was injected and that imaging was captured in real time, since this is what distinguishes fluoroscopy from plain radiography of the same vessels. The specific artery or arterial segment imaged drives the body part selection, and the coder should verify whether the study was purely diagnostic or performed as guidance for an interventional procedure, since guidance fluoroscopy for a separate therapeutic intervention is not coded the same way as a standalone diagnostic arteriogram. A frequent error is failing to capture bilateral studies correctly when both upper extremities were imaged in the same session, or coding the catheter insertion site as the imaged body part instead of the artery actually visualized.

Commonly Confused With

This family is closely related to and often confused with CT angiography of the upper arteries, since both use contrast to visualize the same vessels; the distinguishing factor is that fluoroscopy produces a live, continuously viewed image during contrast injection while CT produces a computer-reconstructed set of cross-sectional images from multiple static exposures. It is also distinguished from plain radiography of the same arteries, which involves no contrast tracking and no real-time viewing, and from ultrasonography, which assesses flow using sound waves rather than ionizing radiation and injected dye.