open access

Vol 24, No 2 (2019)
Original research articles
Published online: 2019-03-01
Submitted: 2018-09-14
Get Citation

Validation of dose distribution computation on sCT images generated from MRI scans by Philips MRCAT

Iva Bratova, Petr Paluska, Jakub Grepl, Petra Sykorova, Jan Jansa, Miroslav Hodek, Igor Sirak, Milan Vosmik, Jiri Petera
DOI: 10.1016/j.rpor.2019.02.001
·
Rep Pract Oncol Radiother 2019;24(2):245-250.

open access

Vol 24, No 2 (2019)
Original research articles
Published online: 2019-03-01
Submitted: 2018-09-14

Abstract

Aim

To evaluate calculation of treatment plans based on synthetic-CT (sCT) images generated from MRI.

Background

Because of better soft tissue contrast, MR images are used in addition to CT images for radiotherapy planning. However, registration of CT and MR images or repositioning between scanning sessions introduce systematic errors, hence suggestions for MRI-only therapy. The lack of information on electron density necessary for dose calculation leads to sCT (synthetic CT) generation. This work presents a comparison of dose distribution calculated on standard CT and sCT.

Materials and methods

10 prostate patients were included in this study. CT and MR images were collected for each patient and then water equivalent (WE) and MRCAT images were generated. The radiation plans were optimized on CT and then recalculated on MRCAT and WE data. 2D gamma analysis was also performed.

Results

The mean differences in the majority of investigated DVH points were in order of 1% up to 10%, including both MRCAT and WE dose distributions. Mean gamma pass for acceptance criteria 1%/1mm were greater than 82.5%. Prescribed doses for target volumes and acceptable doses for organs at risk were met in almost all cases.

Conclusions

The dose calculation accuracy on MRCAT was not significantly compromised in the majority of clinical relevant DVH points. The introduction of MRCAT into practise would eliminate systematic errors, increase patients’ comfort and reduce treatment expenses. Institutions interested in MRCAT commissioning must, however, consider changes to established workflow.

Abstract

Aim

To evaluate calculation of treatment plans based on synthetic-CT (sCT) images generated from MRI.

Background

Because of better soft tissue contrast, MR images are used in addition to CT images for radiotherapy planning. However, registration of CT and MR images or repositioning between scanning sessions introduce systematic errors, hence suggestions for MRI-only therapy. The lack of information on electron density necessary for dose calculation leads to sCT (synthetic CT) generation. This work presents a comparison of dose distribution calculated on standard CT and sCT.

Materials and methods

10 prostate patients were included in this study. CT and MR images were collected for each patient and then water equivalent (WE) and MRCAT images were generated. The radiation plans were optimized on CT and then recalculated on MRCAT and WE data. 2D gamma analysis was also performed.

Results

The mean differences in the majority of investigated DVH points were in order of 1% up to 10%, including both MRCAT and WE dose distributions. Mean gamma pass for acceptance criteria 1%/1mm were greater than 82.5%. Prescribed doses for target volumes and acceptable doses for organs at risk were met in almost all cases.

Conclusions

The dose calculation accuracy on MRCAT was not significantly compromised in the majority of clinical relevant DVH points. The introduction of MRCAT into practise would eliminate systematic errors, increase patients’ comfort and reduce treatment expenses. Institutions interested in MRCAT commissioning must, however, consider changes to established workflow.

Get Citation

Keywords

MRCAT; Prostate cancer; sCT; Radiotherapy

About this article
Title

Validation of dose distribution computation on sCT images generated from MRI scans by Philips MRCAT

Journal

Reports of Practical Oncology and Radiotherapy

Issue

Vol 24, No 2 (2019)

Pages

245-250

Published online

2019-03-01

DOI

10.1016/j.rpor.2019.02.001

Bibliographic record

Rep Pract Oncol Radiother 2019;24(2):245-250.

Keywords

MRCAT
Prostate cancer
sCT
Radiotherapy

Authors

Iva Bratova
Petr Paluska
Jakub Grepl
Petra Sykorova
Jan Jansa
Miroslav Hodek
Igor Sirak
Milan Vosmik
Jiri Petera

Important: This website uses cookies. More >>

The cookies allow us to identify your computer and find out details about your last visit. They remembering whether you've visited the site before, so that you remain logged in - or to help us work out how many new website visitors we get each month. Most internet browsers accept cookies automatically, but you can change the settings of your browser to erase cookies or prevent automatic acceptance if you prefer.

By "Via Medica sp. z o.o." sp.k., ul. Świętokrzyska 73, 80–180 Gdańsk, Poland
tel.:+48 58 320 94 94, fax:+48 58 320 94 60, e-mail: journals@viamedica.pl