Percutaneous Abdominal and Pelvic Biopsies: Comparison of an Electromagnetic Navigation System and CT-Fluoroscopy

Monday, March 6, 2023

12:00 PM – 1:00 PM

Location: Phoenix Convention Center, North Ballroom 120 D

Poster Presenter(s)

Annie M. Zlevor (she/her/hers)

Medical Student
Department of Radiology - UWSMPH

Disclosure(s): No financial relationships to disclose

Author/Co-author(s)

Meridith A. Kisting, MA

Research Assistant
University of Wisconsin Hospitals and Clinics
Allison Couillard, MD

Resident
University of Wisconsin Hospitals and Clinics
AR

Annika Rossebo, n/a

Research Assistant
University of Wisconsin Hospitals and Clinics
TS

Timothy Szczykutowicz, PhD, DABR

Associate Professor
University of Wisconsin School of Medicine and Public Health
LM

Lu Mao, PhD

Associate Professor
University of Wisconsin School of Medicine and Public Health
JW

Jim White, BME

Lab Manager
University of Wisconsin - Madison
MH

Michael Hartung, MD

Assistant Professor
University of Wisconsin
LM

Lori Mankowski-Gettle, MD, MBA

Associate Professor
University of Wisconsin Hospitals and Clinics
JH

J. Louis Hinshaw, MD

Professor
University of Wisconsin School of Medicine and Public Health
PP

Perry Pickhardt, MD

Professor
University of Wisconsin Hospitals and Clinics
Timothy J. Ziemlewicz, MD

Associate Professor of Radiology
University of Wisconsin Hospital and Clinics
MF

Marcia Foltz, RN

Registered Nurse
University of Wisconsin Hospitals and Clinics
FL

Fred T. Lee, Jr., MD

Professor of Radiology, Biomedical Engineering, and Urology
University Of Wisconsin

Disclosure(s):

Annie M. Zlevor: No financial relationships to disclose

Meridith A. Kisting, MA: No financial relationships to disclose

Timothy J. Ziemlewicz, MD: Elephas: Advisory Committee or Review Panel Member (Ongoing), Consultant (Ongoing); Histosonics Inc.: Ownership Interest (Ongoing), Research Grant Recipient (Ongoing); J&J / Ethicon / NeuWave: Consultant (Ongoing), Research Grant Recipient (Ongoing); Medical Engineering Innovations: Ownership Interest (Ongoing), Salaried Employee (Ongoing)

Fred T. Lee, MD, Jr.: Canon Medical Inc., Medical Advisory Board: Board Membership (Ongoing), Contracted Research (Ongoing); Ethicon, Inc.,: Consultant (Ongoing); Histosonics, Inc.: Board Membership (Ongoing), Contracted Research (Ongoing); Medtronic Inc.,: Intellectual Property Rights (Ongoing), Royalties (Ongoing)

Purpose: To compare electromagnetic navigation (EMN) with CT fluoroscopy (CTF) for guiding percutaneous biopsies in the abdomen and pelvis.

Materials and Methods: Retrospective matched-cohort design comparing biopsies of retroperitoneal lymph nodes, renal, adrenal, pelvic, and hepatic masses performed with either EMN (consecutive cases, n=50) or CTF in intermittent mode (n=100). Cases were matched 1:2 (EMN:CTF) for target organ and lesion size (+/- 10 mm). Technical success, diagnostic yield, complication rate, angle of approach to the target, radiation dose to the operator and patient, and procedure time were compared.

Results: The population was well-matched (median age 65 vs. 65 years, target size 2.0 vs. 2.1 cm, distance-to-target 11.4 vs. 10.7 cm, median cores 3 vs. 3, p > 0.05, EMN vs. CTF respectively). Comparing EMN and CTF, technical success (98 vs. 100%), diagnostic yield (98 vs. 95%), complications (2 vs. 5%), false negatives (0 vs. 1%), and median procedure time (33 vs. 31 min) were not statistically different (p > 0.05). Mean radiation dose to the operator was less with EMN than CTF (0.04 vs. 1.2 µGy, p < 0.001), but patient dose was larger (30.1 mSv vs. 9.6 mSv, p < 0.001) due to the greater number of helical scans during EMN guidance (mean 3.9 vs. 2.1, p< 0.001). CTF was performed with a mean of 29.7 tap scans per case. Three (3%) CTF cases were performed with gantry tilt, while the mean angle out of plane for EMN cases was 13.4°.

Conclusion:

Percutaneous biopsies guided by EMN and CTF were closely matched for technical success, diagnostic yield, procedure time, and complications in a matched cohort of patients. EMN cases were more likely to be performed outside of the axial plane. Radiation dose to the operator was higher with CTF, and patient radiation dose was higher with EMN. Further study with a wider array of procedures and anatomic locations appears warranted.