191 - CT-Guided Intervention: Reduction of Metal Artifact Using an Off-Axis Reconstruction Method

Tuesday, April 14, 2026

3:27 PM - 3:36 PM ET

Presenting Author(s)

AM

Ali Mutlu, MD

Research Intern
University of Wisconsin-Madison, United States

Author/Co-author(s)

Allison Couillard, MD

Resident
University of Wisconsin Hospitals and Clinics, United States
Adrienne L. Kisting, MS (she/her/hers)

Research Intern
University of Wisconsin-Madison, United States
Meridith Kisting, MA (she/her/hers)

Medical Student
Carle Illinois College of Medicine, United States
AS

Aria Salyapongse, BS

PhDc
UW-Madison, United States
Anna M. Sorensen, MD, MSc (she/her/hers)

Resident
University of Wisconsin Hospital and Clinics, United States
GF

Gretchen Foltz, MD, FSIR (she/her/hers)

Associate Professor
Madison Radiologists, United States
LH

Louis Hinshaw, MD

Professor
University of Wisconsin School of Medicine and Public Health, United States
TS

Timothy Szczykutowicz, PhD

Professor
U Wisconsin School of Medicine & Public Health, United States
FL

Fred T. Lee, Jr., MD

Professor
University Of Wisconsin, United States
Martin G. Wagner, PhD

Assistant Professor
University of Wisconsin Madison, United States

Purpose: Needle artifact redistribution technique (Needle-ART) is a recently developed prototype method for reducing image artifacts in CT-guided needle procedures. The technique involves tilting the gantry out of the needle plane during scanning, then reformatting the images along the needle plane. The purpose of this study is to evaluate the feasibility, artifact reduction, and clinical applicability of Needle-ART for the placement of biopsy introducer needles into the liver, kidneys, and lungs of a deceased animal model.

Materials and Methods: A paired before-and-after preclinical study in two deceased swine (~50 kg) evaluated Needle-ART for reducing metal artifacts during CT guided interventions. A 17G coaxial needle was placed into liver, lung, and kidney (6 sites per organ) and scanned twice at each site: standard axial (0° gantry, control) and Needle-ART (6° tilted gantry) reconstructions. A total of 48 scans (24 control, 24 Needle-ART) were obtained. Images were reformatted along the needle trajectory, and MATLAB was used to measure artifact, width, and length. Blinded radiologists rated overall artifact severity to qualitatively validate quantitative results.

Results: Needle-ART significantly reduced metal artifacts across all quantitative metrics and in blinded reader assessments. Mean artifact length decreased from 45.6 to 15.6 mm in kidney (65.9%, p=0.003), 47.1 to 19.1 mm in lung (59.4%, p=0.0021), and 46.6 to 30.0 mm in liver (35.5%, p=0.0019). Median artifact width decreased from 5.35 to 4.05 mm in kidney (24.3%, p=0.028), 6.0 to 4.3 mm in lung (8.3%, p=0.017), and 5.0 to 3.5 mm in liver (30%, p=0.028). Median artifact intensity improved from -960.6 to -620.6 HU in kidney (35.4%, p=0.028), -961 to -734.3 HU in lung (23.6%, p=0.021), and -900.5 to -551 HU in liver (38.8%, p=0.011). Three blinded radiologists scored conventional CT needle images with significantly worse artifacts (median=3) compared to Needle-ART images (median=2, p=0.000041).

Conclusion: Needle-ART is effective for reducing metal artifacts during CT-guided interventions in this deceased animal model. Future work includes integrating and automating Needle-ART into clinical CT scanners and obtaining regulatory approval for human clinical use.