Display options
Cite
Ruder TD, Thali Y, Schindera ST, et al. How reliable are Hounsfield-unit measurements in forensic radiology?. Forensic Sci Int. 2012;220(1):219-23doi: 10.1016/j.forsciint.2012.03.004.
Ruder, T. D., Thali, Y., Schindera, S. T., Dalla Torre, S. A., Zech, W. D., Thali, M. J., Ross, S., & Hatch, G. M. (2012). How reliable are Hounsfield-unit measurements in forensic radiology?. Forensic science international, 220(1), 219-23. https://doi.org/10.1016/j.forsciint.2012.03.004
Ruder, Thomas D, et al. "How reliable are Hounsfield-unit measurements in forensic radiology?." Forensic science international vol. 220,1 (2012): 219-23. doi: https://doi.org/10.1016/j.forsciint.2012.03.004
Ruder TD, Thali Y, Schindera ST, Dalla Torre SA, Zech WD, Thali MJ, Ross S, Hatch GM. How reliable are Hounsfield-unit measurements in forensic radiology?. Forensic Sci Int. 2012 Jul 10;220(1):219-23. doi: 10.1016/j.forsciint.2012.03.004. Epub 2012 Apr 23. PMID: 22534158.
Copy Download .nbib Format: NLM
Share it on

Forensic Sci Int. 2012 Jul 10;220(1):219-23. doi: 10.1016/j.forsciint.2012.03.004. Epub 2012 Apr 23.

How reliable are Hounsfield-unit measurements in forensic radiology?.

Forensic science international

Thomas D Ruder, Yannick Thali, Sebastian T Schindera, Simon A Dalla Torre, Wolf-Dieter Zech, Michael J Thali, Steffen Ross, Gary M Hatch

Affiliations

  1. Center of Forensic Imaging and Virtopsy, Institute of Forensic Medicine, University of Bern, Buehlstrasse 20, CH-3012 Bern, Switzerland. [email protected]

PMID: 22534158 DOI: 10.1016/j.forsciint.2012.03.004

Abstract

OBJECTIVE: To assess the reliability of computed tomography (CT) numbers, also known as Hounsfield-units (HU) in the differentiation and identification of forensically relevant materials and to provide instructions to improve the reproducibility of HU measurements in daily forensic practice.

MATERIALS AND METHODS: We scanned a phantom containing non-organic materials (glass, rocks and metals) on three different CT scanners with standardized parameters. The t-test was used to assess the influence of the scanner, the size and shape of different types of regions-of-interest (ROI), the composition and shape of the object, and the reader performance on HU measurements. Intra-class correlation coefficient was used to assess intra- and inter-reader reliability.

RESULTS: HU values did not change significantly as a function of ROI-shape or -size (p>0.05). Intra-reader reliability reached ICC values >0.929 (p<0.001). Inter-reader reliability was also excellent with an ICC of 0.994 (p<0.001). Four of seven objects yielded significantly different CT numbers at different levels within the object (p<0.05). In 6/7 objects the HU changed significantly from CT scanner to CT scanner (p<0.05).

CONCLUSION: Reproducible CT number measurements can be achieved through correct ROI-placement and repeat measurements within the object of interest. However, HU may differ from CT-scanner to CT-scanner. In order to obtain comparable CT numbers we suggest that a dedicated Forensic Reference Phantom be developed.

Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

Publication Types