Metal implants on abdominal CT: does split-filter dual-energy CT provide additional value over iterative metal artifact reduction?

Hildegard M Wichtmann; Kai R Laukamp; Sebastian Manneck; Konrad Appelt; Bram Stieltjes; Daniel T Boll; Matthias R Benz; Markus M Obmann

doi:10.1007/s00261-022-03682-3

Metal implants on abdominal CT: does split-filter dual-energy CT provide additional value over iterative metal artifact reduction?

Abdom Radiol (NY). 2023 Jan;48(1):424-435. doi: 10.1007/s00261-022-03682-3. Epub 2022 Sep 30.

Authors

Hildegard M Wichtmann¹, Kai R Laukamp², Sebastian Manneck¹, Konrad Appelt¹, Bram Stieltjes¹, Daniel T Boll¹, Matthias R Benz^{1

3}, Markus M Obmann⁴

Affiliations

¹ Clinic of Radiology and Nuclear Medicine, University Hospital Basel, University of Basel, Petersgraben 4, CH-4031, Basel, Switzerland.
² Department of Diagnostic and Interventional Radiology, University Hospital Cologne, Cologne, Germany.
³ Department of Molecular and Medical Pharmacology, University of California Los Angeles, Los Angeles, CA, USA.
⁴ Clinic of Radiology and Nuclear Medicine, University Hospital Basel, University of Basel, Petersgraben 4, CH-4031, Basel, Switzerland. Markus.Obmann@usb.ch.

Abstract

Purpose: To assess image quality and metal artifact reduction in split-filter dual-energy CT (sfDECT) of the abdomen with hip or spinal implants using virtual monoenergetic images (VMI) and iterative metal artifact reduction algorithm (iMAR).

Methods: 102 portal-venous abdominal sfDECTs of patients with hip (n = 71) or spinal implants (n = 31) were included in this study. Images were reconstructed as 120kVp-equivalent images (Mixed) and VMI (40-190 keV), with and without iMAR. Quantitative artifact and image noise was measured using 12 different ROIs. Subjective image quality was rated by two readers using a five-point Likert-scale in six categories, including overall image quality and vascular contrast.

Results: Lowest quantitative artifact in both hip and spinal implants was measured in VMI_190keV-iMAR. However, it was not significantly lower than in Mixed_iMAR (for all ROIs, p = 1.00), which were rated best for overall image quality (hip: 1.00 [IQR: 1.00-2.00], spine: 3.00 [IQR:2.00-3.00]). VMI_50keV-iMAR was rated best for vascular contrast (hip: 1.00 [IQR: 1.00-2.00], spine: 2.00 [IQR: 1.00-2.00]), which was significantly better than Mixed (both, p < 0.001). VMI_50keV-iMAR provided superior overall image quality compared to Mixed for hip (1.00 vs 2.00, p < 0.001) and similar diagnostic image quality for spinal implants (2.00 vs 2.00, p = 0.51).

Conclusion: For abdominal sfDECT with hip or spinal implants Mixed_iMAR images should be used. High keV VMI do not further improve image quality. IMAR allows the use of low keV images (VMI_50keV) to improve vascular contrast, compared to Mixed images.

Keywords: Arthroplasty; Artifacts; Dual-energy x-ray computed tomography; Hip; Spine.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Abdomen
Algorithms
Artifacts*
Humans
Metals
Prostheses and Implants
Tomography, X-Ray Computed* / methods

Substances

Metals