Dataset Information

Comparison of internal target volumes defined by three-dimensional, four-dimensional, and cone-beam computed tomography images of a motion phantom.

ABSTRACT:

Background

To explore the variations of the gross tumor volume (GTV) from different three-dimensional computed tomography (3DCT) scan modes and the consistency of internal target volume (ITV) between different 3DCT, cone-beam computed tomography (CBCT) and four-dimensional computed tomography (4DCT) scan, a study using a motion phantom simulating sinusoidal movement was conducted.

Methods

For three 3DCT scan modes: the GTV was contoured, and ITV_I was generated on the basis of GTV with a 10-mm margin while ITV_II and ITV_III with a 0-mm margin on the motion direction. ITV_CBCT and ITV_MIP were contoured on the images of CBCT and maximum-intensity projection (MIP) reconstructed 4DCT images. The centroid position shifts of ITVs were analyzed. The volume consistency between ITV_I, ITV_II, ITV_III and ITV_MIP were evaluated by calculating the Dice similarity coefficient (Dsc) and the value of Δ Volume (ΔV). Furthermore, the 3DCT and CBCT images from 12 NSCLC patients were retrospectively collected, then the Dsc and ΔV were calculated.

Results

The mean ± standard deviation of centroid position of ITV_I, ITV_II and ITV_III were 2.3±4.7, 2.6±4.0, and 1.0±1.4 mm, respectively. The mean ± standard deviation of Dsc between ITV_I, ITV_II, ITV_III and ITV_MIP were 0.78±0.77, 0.86±0.1, and 0.94±0.05, respectively. The ΔV of ITV_I, ITV_II, ITV_III were 29.67%, 17.22%, and 6.46%, respectively. The ITV from CBCT showed a deduction rate of 3.1-9.3% compared to 4DCT. For the patients, the mean Dsc andΔV between ITV_I and ITV_CBCT were 0.50 and 60.76%.

Conclusions

The GTV acquired from 3DCT scan mode I possessed great deviation of centroid position and target volume. ITV on the basis of this GTV was significantly larger than ITV_MIP. A good similarity was showed between ITV_III and ITV_MIP, 4DCT is still a golden standard for the ITV delineation, but in the absence of 4DCT, image from 3DCT scan mode III and KV-CBCT may be considered for ITV delineation with caution.

SUBMITTER: Wang Y

PROVIDER: S-EPMC7729323 | biostudies-literature | 2020 Nov

REPOSITORIES: biostudies-literature

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Publications

Comparison of internal target volumes defined by three-dimensional, four-dimensional, and cone-beam computed tomography images of a motion phantom.

Wang Yu Y Liu Tao T Chen Huiqin H Bai Penggang P Zhan Qiong Q Liang Xiaohua X

Annals of translational medicine 20201101 22

<h4>Background</h4>To explore the variations of the gross tumor volume (GTV) from different three-dimensional computed tomography (3DCT) scan modes and the consistency of internal target volume (ITV) between different 3DCT, cone-beam computed tomography (CBCT) and four-dimensional computed tomography (4DCT) scan, a study using a motion phantom simulating sinusoidal movement was conducted.<h4>Methods</h4>For three 3DCT scan modes: the GTV was contoured, and ITV<sub>I</sub> was generated on the ba ...[more]

PMID: 33313233

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Dataset Information

Comparison of internal target volumes defined by three-dimensional, four-dimensional, and cone-beam computed tomography images of a motion phantom.

Background

Methods

Results

Conclusions

Publications

Comparison of internal target volumes defined by three-dimensional, four-dimensional, and cone-beam computed tomography images of a motion phantom.

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