Hostname: page-component-cd9895bd7-q99xh Total loading time: 0 Render date: 2024-12-26T20:57:49.764Z Has data issue: false hasContentIssue false
  • English
  • Français

Improved visualisation of cervix applicators for magnetic resonance-only-guided brachytherapy planning

Published online by Cambridge University Press:  22 January 2014

Gary P. Liney ,
Jenny E. Marsden ,
Carl J. Horsfield ,
Tom Murray ,
David J. Manton  and
Andrew W. Beavis
Gary P. Liney
Affiliation:
Radiation Physics Department, Queen's Centre for Oncology and Haematology, Hull & East Yorkshire Hospitals NHS Trust, Castle Hill Hospital, Cottingham, East Yorkshire, UK
Jenny E. Marsden
Affiliation:
Radiation Physics Department, Queen's Centre for Oncology and Haematology, Hull & East Yorkshire Hospitals NHS Trust, Castle Hill Hospital, Cottingham, East Yorkshire, UK
Carl J. Horsfield
Affiliation:
Radiation Physics Department, Queen's Centre for Oncology and Haematology, Hull & East Yorkshire Hospitals NHS Trust, Castle Hill Hospital, Cottingham, East Yorkshire, UK
Tom Murray
Affiliation:
Radiation Physics Department, Queen's Centre for Oncology and Haematology, Hull & East Yorkshire Hospitals NHS Trust, Castle Hill Hospital, Cottingham, East Yorkshire, UK
David J. Manton
Affiliation:
Radiation Physics Department, Queen's Centre for Oncology and Haematology, Hull & East Yorkshire Hospitals NHS Trust, Castle Hill Hospital, Cottingham, East Yorkshire, UK
Andrew W. Beavis*
Affiliation:
Radiation Physics Department, Queen's Centre for Oncology and Haematology, Hull & East Yorkshire Hospitals NHS Trust, Castle Hill Hospital, Cottingham, East Yorkshire, UK
*
Correspondence to: Andrew W. Beavis, Radiation Physics Department, Queen's Centre for Oncology and Haematology, Castle Hill Hospital, Cottingham, East Yorkshire, HU16 5JQ, UK. Tel. 01482 461384. E-mail: [email protected].
Get access Rights & Permissions [Opens in a new window]

Abstract

Objectives

Current guidelines for image-guided cervical cancer brachytherapy planning recommend both computed tomography (CT) and magnetic resonance imaging (MRI) for adequate visualisation of the applicator and soft tissues, respectively. MRI-only planning would be ideal as it would save time within the patient pathway and avoid the concomitant CT exposures. However, applicator visualisation on MRI is usually achieved using fluid-filled fiducial marker tubes, which can be awkward to use and suffer from unwanted air bubble artefacts. Therefore, a new fiducial-free imaging technique was developed.

Methods

A dual echo time (TE) turbo spin echo sequence was used, at 1·5 T, to provide both T2-weighted images (100 ms TE) for tissue visualisation and strongly proton density-weighted images (17 ms TE) for improved applicator visualisation. In-house software was used to automatically segment the applicator in the short TE images (using Otsu's method) and transfer the information to the long TE images to provide a single fused dataset.

Results

The method was evaluated successfully using titanium applicators in three patient cases and using a plastic applicator in a tissue-equivalent gel phantom.

Conclusions

The dual-echo technique provides a simple and efficient method for improving the visualisation of brachytherapy applicators in cervical cancer MRI images without the need for marker tubes.

Keywords

applicatorbrachytherapycervixdual echoHDRIGBTMR onlyMRIplanningsequencevisualisation
Type
Original Articles
Information
Journal of Radiotherapy in Practice , Volume 13 , Issue 2 , June 2014 , pp. 159 - 165
Copyright
Copyright © Cambridge University Press 2014 

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

1.Haie-Meder, C, Potter, R, Van Limbergen, Eet al. Recommendations from gynaecological (GYN) GEC-ESTRO working group (I): concepts and terms in 3D image based 3D treatment planning in cervix cancer brachytherapy with emphasis on MRI assessment of GTV and CTV. Radiother Oncol 2005; 74: 235–245.Google Scholar
2.Hellebust, T P, Kirisits, C, Berger, Det al. Recommendations from gynaecological (GYN) GEC-ESTRO working group: considerations and pitfalls in commissioning and applicator reconstruction in 3D image-based treatment planning of cervix cancer brachytherapy. Radiother Oncol 2010; 96: 153–160.Google Scholar
3.Willis, R, Lowe, G, Inchely, D, Anderson, C, Beenstock, V, Hoskin, P. Applicator reconstruction for HDR cervix treatment planning using images from 0.35T open MR scanner. Radiother Oncol 2010; 94: 346–352.Google Scholar
4.Haack, S, Nielson, S K, Lindegaard, J C, Gelineck, J, Tanderup, K. Applicator reconstruction in MRI 3D image-based dose planning of brachytherapy for cervical cancer. Radiother Oncol 2009; 91: 187–193.Google Scholar
5.Perez-Calatayud, J, Kuipers, F, Ballester, Fet al. Exclusive MRI-based tandem and colpostats reconstruction in gynaecological brachytherapy treatment planning. Radiother Oncol 2009; 91: 181–186.Google Scholar
6.Berger, D, Dimopoulos, J, Potter, R, Kiristis, C. Direct reconstruction of the Vienna applicator on MR images. Radiother Oncol 2009; 93: 347–351.Google Scholar
7.Otsu, N. A threshold selection method from gray-level histograms. IEEE Trans Syst Man Cybern 1979; 9: 62–66.Google Scholar
8.Liney, G P, Heathcote, A, Jenner, A, Turnbull, L W, Beavis, A W. Absolute radiation dose verification using magnetic resonance imaging I: feasibility study. J Radiother Pract 2003; 3: 120–127.Google Scholar
9.Moore, C S, Liney, G P, Beavis, A W. A quality assurance phantom for verification and registration of CT and MRI data sets for treatment planning of radiotherapy for head and neck cancers. J Appl Clin Med Phys 2004; 22: 25–35.Google Scholar
10.Robson, M D, Benjamin, M, Gishen, P, Bydder, G M. Magnetic resonance imaging of the Achilles tendon using ultrashort TE (UTE) pulse sequences. Clin Radiol 2004; 59: 727–735.Google Scholar