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Comparative Study
. 2020 Dec 1;93(1116):20200152.
doi: 10.1259/bjr.20200152. Epub 2020 Oct 1.

Comparison of virtual non-contrast dual-energy CT and a true non-contrast CT for contouring in radiotherapy of 3D printed lung tumour models in motion: a phantom study

Dominik Alexander Hering  1 , Kai Kröger  1 , Ralf W Bauer  2 , Hans Theodor Eich  1 , Uwe Haverkamp  1
Affiliations
Comparative Study

Comparison of virtual non-contrast dual-energy CT and a true non-contrast CT for contouring in radiotherapy of 3D printed lung tumour models in motion: a phantom study

Dominik Alexander Hering et al. Br J Radiol. .

Abstract

Objectives: This work aims to investigate whether virtual non-contrast (VNC) dual-energy CT(DECT) of contrasted lung tumours can be used as an alternative for true non-contrast (TNC) images in radiotherapy. Two DECT techniques and a TNC CT were compared and influences on gross tumour volume (GTV) volume and CT number from motion artefacts in three-dimensional printed lung tumour models (LTM) in amotion phantom were examined.

Methods: Two spherical LTMs (diameter 3.0 cm) with different inner shapes were created in a three-dimensional printer. The inner shapes contained water or iodine (concentration 5 mg ml-1) and were scanned with a dual-source DECT (ds-DECT), single-source sequential DECT (ss-DECT) and TNC CT in a respiratory motion phantom (15 breaths/min, amplitude 1.5 cm). CT number and volume of LTMs were measured. Therefore, two GTVs were contoured.

Results: Deviations in GTV volume (outer shape) of LTMs in motion for contrast-enhanced ss-DECT and ds-DECT VNC images compared to TNC images are not significant (p > 0.05). Relative GTV volume and CT number deviations (inner shapes) of LTMs in motion were 6.6 ± 0.6% and 104.4 ± 71.2 HU between ss-DECT and TNC CT and -8.4 ± 10.6% and 25.5 ± 58.5 HU between ds-DECT and TNC, respectively.

Conclusion: ss-DECT VNC images could not sufficiently subtract iodine from water in LTMs inmotion, whereas ds-DECT VNC images might be a valid alternative to a TNC CT.

Advances in knowledge: ds-DECT provides a contrasted image for contouring and a non-contrasted image for radiotherapy treatment planning for LTM in motion.

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Figures

Figure 1.
Figure 1.
Image of the opened lung insert made of cedarwood with a 3 cm spherically cavity for the matching 3D printed lung tumour model. 3D, three-dimensional.
Figure 2.
Figure 2.
Implementation of the 3D printed LTM. The top images show the drafts of two different shaped LTMs and the bottom images the corresponding coronal plane in CT images. Left: LTM-1, right: LTM-2. 3D, three-dimensional; LTM, lung tumour model.
Figure 3.
Figure 3.
Coronal plane of a single scan of VNC and TNC images of LTMs in motion. The contoured lines of the outer GTV, ITV-O, inner GTV-I and ITV-I are shown (window level −500 HU; window width 500 HU). Top images show LTM-1 and bottom LTM-2. From left to right: TNC radiotherapy CT, TNC radiotherapy CT ITV,VNC dual-source DECT,VNC single-source sequential DECT. DECT, dual-energy CT; GTV, gross tumour volume; HU, Hounsfield unit; ITV, internal target volume; LTM, lung tumour model; TNC, true non-contrast; VNC, virtual non-contrast.
Figure 4.
Figure 4.
Axial plane of a single scan of VNC and TNC images of LTM in motion. The outer GTV-O and GTV-I are shown (window level 40 HU; window width 400 HU). Top images show LTM-1 and bottom LTM-2. Left: TNC radiotherapy CT, middle: VNC dual-source DECT images, right: VNC single-source sequential DECT images DECT, dual-energy CT; GTV, gross tumour volume; HU, Hounsfield unit; ITV, internal target volume; LTM, lung tumour model; TNC, true non-contrast; VNC, virtual non-contrast.
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References

    1. Schwahofer A, Bär E, Kuchenbecker S, Grossmann JG, Kachelrieß M, Sterzing F. The application of metal artifact reduction (MAR) in CT scans for radiation oncology by monoenergetic extrapolation with a DECT scanner. Z Med Phys 2015; 25: 314–25. doi: 10.1016/j.zemedi.2015.05.004 - DOI - PubMed
    1. Mangold S, Gatidis S, Luz O, König B, Schabel C, Bongers MN, et al. . Single-Source dual-energy computed tomography: use of monoenergetic extrapolation for a reduction of metal artifacts. Invest Radiol 2014; 49: 788–93. doi: 10.1097/RLI.0000000000000083 - DOI - PubMed
    1. Bamberg F, Dierks A, Nikolaou K, Reiser MF, Becker CR, Johnson TRC. Metal artifact reduction by dual energy computed tomography using monoenergetic extrapolation. Eur Radiol 2011; 21: 1424–9. doi: 10.1007/s00330-011-2062-1 - DOI - PubMed
    1. Andersson KM, Nowik P, Persliden J, Thunberg P, Norrman E. Metal artefact reduction in CT imaging of hip prostheses—an evaluation of commercial techniques provided by four vendors. Br J Radiol 2015; 88: 20140473. doi: 10.1259/bjr.20140473 - DOI - PMC - PubMed
    1. Sheen H, Shin H-B, Cho S, Cho J, Han Y. Feasibility of dual-energy computed tomography in radiation therapy planning. J Korean Phys Soc 2017; 71: 1056–63. doi: 10.3938/jkps.71.1056 - DOI

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