Dataset Information

Comparison of four dimensional computed tomography and magnetic resonance imaging in abdominal radiotherapy planning.

ABSTRACT:

Background and purpose

Four-dimensional (4D) computed tomography (CT) is widely used in radiotherapy (RT) planning and remains the current standard for motion evaluation. We assess a 4D magnetic resonance imaging (MRI) sequence in terms of motion and image quality in a phantom, healthy volunteers and patients undergoing RT.

Materials and methods

The 4D-MRI sequence is a prototype T1-weighted 3D gradient echo with radial acquisition with self-gating. The accuracy of the 4D-MRI respiratory sorting based method was assessed using a MRI-CT compatible respiratory simulation phantom. In volunteers, abdominal viscera were evaluated for artefact, noise, structure delineation and overall image quality using a previously published four-point scoring system. In patients undergoing abdominal RT, the tumour (or a surrogate) was utilized to assess the range of motion on both 4D-CT and 4D-MRI. Furthermore, imaging quality was evaluated for both 4D-CT and 4D-MRI.

Results

In phantom studies 4D-MRI demonstrated amplitude of motion error of less than 0.2?mm for five, seven and ten bins. 4D-MRI provided excellent image quality for liver, kidney and pancreas. In patients, the median amplitude of motion seen on 4D-CT and 4D-MRI was 11.2?mm (range 2.8-20.3?mm) and 10.1?mm (range 0.7-20.7?mm) respectively. The median difference in amplitude between 4D-CT and 4D-MRI was -0.6?mm (range -3.4-5.2?mm). 4D-MRI demonstrated superior edge detection (median score 3 versus 1) and overall image quality (median score 2 versus 1) compared to 4D-CT.

Conclusions

The prototype 4D-MRI sequence demonstrated promising results and may be used in abdominal targeting, motion gating, and towards implementing MRI-based adaptive RT.

SUBMITTER: Oar A

PROVIDER: S-EPMC7807635 | biostudies-literature | 2018 Jul

REPOSITORIES: biostudies-literature

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Publications

Comparison of four dimensional computed tomography and magnetic resonance imaging in abdominal radiotherapy planning.

Oar Andrew A Liney Gary G Rai Robba R Deshpande Shrikant S Pan Li L Johnston Meredith M Jameson Michael M Kumar Shivani S Lee Mark M

Physics and imaging in radiation oncology 20180701

<h4>Background and purpose</h4>Four-dimensional (4D) computed tomography (CT) is widely used in radiotherapy (RT) planning and remains the current standard for motion evaluation. We assess a 4D magnetic resonance imaging (MRI) sequence in terms of motion and image quality in a phantom, healthy volunteers and patients undergoing RT.<h4>Materials and methods</h4>The 4D-MRI sequence is a prototype T1-weighted 3D gradient echo with radial acquisition with self-gating. The accuracy of the 4D-MRI resp ...[more]

PMID: 33458408

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Dataset Information

Comparison of four dimensional computed tomography and magnetic resonance imaging in abdominal radiotherapy planning.

Background and purpose

Materials and methods

Results

Conclusions

Publications

Comparison of four dimensional computed tomography and magnetic resonance imaging in abdominal radiotherapy planning.

Similar Datasets

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