Secondary Logo

Journal Logo

Institutional members access full text with Ovid®

Manual and Fully Automated Segmentation to Determine the Ferromagnetic Status of Bullets Using Computed Tomography Dual-Energy Index

A Phantom Study

Ognard, Julien MD, PhD*,†; Dissaux, Brieg MD, MSc*; Diallo, Idris MD; Attar, Lakdar MSc§; Saccardy, Claire MD; Ben Salem, Douraied MD, PhD*,†

Journal of Computer Assisted Tomography: September/October 2019 - Volume 43 - Issue 5 - p 799–804
doi: 10.1097/RCT.0000000000000899
Technical Developments
Buy
SDC

Objective The aim was to determine if dual-energy computed tomography (DECT) can discriminate ferromagnetic bullets from nonferromagnetic ones.

Methods The ferromagnetic properties of 29 bullets were determined. All bullets underwent a DECT evaluation, and a manual measurement of the dual-energy index was performed by 2 radiologists, followed by a fully automatic measurement, in 3 different positions in a phantom (air, water, and bone).

Results Twenty-one bullets were found to be nonferromagnetic. There were significant differences between the mean of the dual-energy index measured in the core of ferromagnetic projectiles and those of nonferromagnetic ones in the lung position of the phantom (P = 0.007). Specificity was 86.36%, and negative predictive value was 90.48%. Among the 29 bullets, 24 were correctly classified.

Conclusions Our study demonstrates that DECT can assess the ferromagnetic status of bullets and their magnetic resonance imaging compatibility using an extended computed tomography scale in an ex vivo phantom model.

From the *Forensic Imaging Unit, University Hospital of Brest

Laboratoire de traitement de l'information médicale—LaTIM (Inserm UMR 1101), Brest

Imaging and Radiology Service, Cornouaille Hospital of Quimper, Quimper

§French National Forensic Science Institute, Lyon

Clinical Forensic Medicine and Pathology, University Hospital of Brest, Brest, France.

Received for publication December 27, 2018; accepted May 23, 2019.

Correspondence to: Julien Ognard, MD, PhD, Service d'Imagerie Médicale, CHU de la Cavale Blanche, Boulevard Tanguy-Prigent, 29609 Brest, France (e-mail: julien.ognard@chu-brest.fr).

The authors declare no conflict of interest.

Supplemental digital content is available for this article. Direct URL citations appear in the printed text and are provided in the HTML and PDF versions of this article on the journal’s Web site (www.jcat.org).

Online date: July 29, 2019

Copyright © 2019 Wolters Kluwer Health, Inc. All rights reserved.