Finding the “Invisible” Object: Evaluation and Retrieval of Radiolucent Intravascular Foreign Bodies

Monday, March 6, 2023

5:10 PM – 5:15 PM

Location: Phoenix Convention Center, North Ballroom 120ABC, Poster Hall

Abstract Presenter(s)

RL

Richard X. Liu, MHS

Medical Student
University of Cincinnati College of Medicine

Disclosure(s): No financial relationships to disclose

Author/Co-author(s)

Ali Kord, MD, MPH

Assistant Professor of Radiology
University of Cincinnati Medical Center
Lulu Zhang, MD

Assistant Professor of Radiology
University of Cincinnati Medical Center
SK

Stephanie H. Kim, MD, PhD

Assistant Professor of Radiology
University of Cincinnati Medical Center

Disclosure(s):

Richard X. Liu, MHS: No financial relationships to disclose

Ali Kord, MD, MPH: No financial relationships to disclose

Lulu Zhang, MD: No financial relationships to disclose

Learning Objectives:

To present cases of radiolucent intravascular foreign bodies

Describe the clinical and imaging evaluation of these intravascular foreign bodies, for the purpose of identification and/or removal

Discuss decision making and techniques for removal of intravascular foreign bodies difficult to visualize by fluoroscopy

Background:

Interventional Radiologists receive requests for evaluation and retrieval of intravascular foreign bodies (IFBs). Successful removal can mitigate potential adverse events. Though most IFB are seen by computed tomography (CT), not all are readily visible on fluoroscopy. Limited visibility can result in difficulty identifying the IFB. While radiographically distinct IFB may be identified as endovascular devices, radiolucent IFBs have a broader differential, which includes procedural (endovascular and non-endovascular), extrinsic, and physiologic etiologies. The safety, feasibility, and necessity of removal must be considered, especially for objects not intended for intravascular use. Review of clinical and imaging data can help ascertain the identity of an IFB. Removal is challenging due to limited visibility; a combination of fluoroscopy, sonography, and anatomic knowledge can provide guidance.

Clinical Findings/Procedure Details:

A pictorial review of several cases from our institution illustrates the evaluation, assessment, and retrieval of IFB not readily visible by fluoroscopy and/or radiography. The imaging appearances of objects suspected to represent IFBs on CT are shown, including an ingested object, a presumptive unraveled coil, and a fibrin sheath. Technical considerations during removal are presented in the following cases: 1) a linear pulmonary arterial object, of unknown etiology and chronicity and 2) a plastic tubule in the central veins visualized using intravascular ultrasound. Factors that may affect the risk-benefit ratio of removing radiolucent IFBs are discussed.

Conclusion and/or Teaching Points:

The identification and removal of radiolucent intravascular foreign bodies are technically challenging. This presentation demonstrates a range of objects that these IFB may represent, as well as the importance of characterization prior to any removal attempts. The viewer will be introduced to intravascular techniques and considerations for removal of these “invisible” IFBs.