Use of an Electromagnetic Navigation System on a Phantom as a Training Simulator for CT-Guided Procedures

Description of the problem
CT-guided procedures are an essential part of the clinical work at many hospitals across the United States and throughout the world. CT guidance is used for biopsies, abscess drainages, and ablations. Currently, radiology residents and fellows acquire their CT procedural skills on real patients. Both diagnostic and interventional radiologists perform some of these procedures, and therefore the experience and skill set in performing these procedures can vary widely.

Although CT-guided procedures have been used to successfully diagnose and treat a wide range of pathologies, it is at the expense of increased radiation exposure to both operators and patients. Limiting radiation exposure in interventional radiology has been an important discussion point, and societies such as the Cardiovascular and Interventional Radiological Society of Europe and the Society of Interventional Radiology have provided strong recommendations in an effort to reduce excessive radiation exposure.

Over the past several years, multiple new navigational tools have entered the market, helping guide fully trained interventional radiologists during CT-guided procedures. Using fiducials and optical or electromagnetic tracking, these tools create a “global positioning system” of the internal organs and can allow the needle to be tracked in real time. These navigational tools also allow a simulated CT experience, enabling a phantom to be imaged on a CT scanner and a biopsy procedure simulated at a location and time separate from the planning CT scan, without the need for additional radiation to the patient and operator.

Although navigational systems may offer an alternative for training and performing CT-guided procedures in the future for both interventional and noninterventional radiologists, little is known about the difficulty and the amount of procedural experience needed to successfully use these navigational systems.

The purpose of this study was to compare the diagnostic and interventional radiologist trainee’s CT-guided procedural skills using an electromagnetic navigational guidance system (EMN, Imactis, La Tronche, France) that mimics a CT-guided biopsy and determine whether prior experience predicts technical success using these systems.

Methods
This prospective study was reviewed and exempted by the institutional review board. A total of 19 fellows (12 interventional fellows and 7 diagnostic fellows) participated in the study. The study was performed 3 months into the fellows’ training (September 2014).

The study consisted of a skills test that simulated a CT-guided procedure. The simulation consisted of two parts: One part allowed targeting of three progressively difficult lesions on a phantom using standard manual/conventional skills. A second part tested targeting of the same lesions using an EMN.

Publication of study protocol
Use of an Electromagnetic Navigation System on a Phantom as a Training Simulator for CT-Guided Procedures, Yadiel Sánchez, BA, Dmitry S. Trifanov, MD, Taj M. Kattapuram, MD, Haiyang Tao, MD, PhD, Anand M. Prabhakar, MD, MBA, Ronald S. Arellano, MD, Raul N. Uppot, MD

Published on JACR (Journal of the American College of Radiology), June 2017, Volume 14, Issue 6, Pages 795–799