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High-­dose rate intraluminal brachytherapy for oesophageal cancer using MR imaging: A clinical implementation

Reci, Rrezarta (2015) MSFT01 20151
Medical Physics Programme
Medical Radiation Physics, Lund
Abstract
Purpose: The aim of this study was to investigate a new methodology for
brachytherapy of oesophageal cancer using magnetic resonance (MR) imaging
for treatment planning. That includes finding a suitable oesophageal applicator
that can be visualised on MR images and to create dose and fraction schedule
that should be used brachytherapy treatments.

Material and Methods: A total of six patients were involved to determine a
suitable MR sequence for visualisation of the oesophageal tumour. The patients
were scanned with two different T2-weighted sequences, inversion recovery fast
spin echo (IR FSE) and fast recovery fast spin echo (FRFSE). The imaging was
performed on a 3.0 T MR scanner from GE Healthcare. Dose planning was
... (More)
Purpose: The aim of this study was to investigate a new methodology for
brachytherapy of oesophageal cancer using magnetic resonance (MR) imaging
for treatment planning. That includes finding a suitable oesophageal applicator
that can be visualised on MR images and to create dose and fraction schedule
that should be used brachytherapy treatments.

Material and Methods: A total of six patients were involved to determine a
suitable MR sequence for visualisation of the oesophageal tumour. The patients
were scanned with two different T2-weighted sequences, inversion recovery fast
spin echo (IR FSE) and fast recovery fast spin echo (FRFSE). The imaging was
performed on a 3.0 T MR scanner from GE Healthcare. Dose planning was
performed on MR images using two different methods. In the first method the
dose was prescribed at 10 mm from the applicator centre, as currently used at
Skåne University Hospital. In the second method the dose planning was
performed by manually adjusting the dwell times until tumour coverage was
reached. An MR safe oesophageal applicator could not be found on the market.
Therefore a duodenal tube was used and modified. Different contrast agents were
studied in order to render the tube visible on MR images.

Results: The oesophageal tumour was successfully visualised and delineated on
T2-weighted images with FRFSE sequences. Furthermore, improved dose
coverage to the tumour was observed when the dose planning was manually
optimised to the tumour volume, where V100% to the tumour was increased from
70% to 95%. Moreover, the applicator was filled with a saline solution and was
visualised on the MR images.

Conclusion: Brachytherapy treatment for oesophageal cancer with MR imaging
provides an improved tumour visualisation and the manifesting of DVH
parameters enables dose coverage to the tumour. (Less)
Popular Abstract (Swedish)
Strålbehandling är en vanlig behandlingsteknik för behandling av cancer.
Behandlingen kan levereras på två olika sätt: internt eller externt. Vid extern
strålbehandling bestrålas tumören med en strålkälla som befinner sig utanför
kroppen. Vid intern strålbehandling, även kallat brachybehandling, placeras
strålkällan inuti kroppen, i eller i nära anslutning till tumören. Själva tumören får
därmed mycket strålning samtidigt som omkringliggande vävnad skonas.

Vid brachybehandling av cancer i matstrupen förs en radioaktiv strålkälla ner i
matstrupen genom en sond. Strålkällan stannar i ett antal bestämda positioner till
dess att tumören mottagit den dos läkaren har ordinerat. Dagens
behandlingsplaner utförs på en röntgenbild med... (More)
Strålbehandling är en vanlig behandlingsteknik för behandling av cancer.
Behandlingen kan levereras på två olika sätt: internt eller externt. Vid extern
strålbehandling bestrålas tumören med en strålkälla som befinner sig utanför
kroppen. Vid intern strålbehandling, även kallat brachybehandling, placeras
strålkällan inuti kroppen, i eller i nära anslutning till tumören. Själva tumören får
därmed mycket strålning samtidigt som omkringliggande vävnad skonas.

Vid brachybehandling av cancer i matstrupen förs en radioaktiv strålkälla ner i
matstrupen genom en sond. Strålkällan stannar i ett antal bestämda positioner till
dess att tumören mottagit den dos läkaren har ordinerat. Dagens
behandlingsplaner utförs på en röntgenbild med hjälp av markörer som markerar
tumörens utsträckning. På grund av otillräcklig information i röntgenbilden kan
inte tumörens volym bestämmas, vilket kan medföra att tumören erhåller felaktig
dos.

Information om tumörens volym kan däremot fås genom tredimensionella bilder
från en magnetisk resonanstomografi (MR) kamera. Dessa bilder ger möjligheten
att urskilja olika vävnader i kroppen, vilket gör det lättare att separera tumören
från omkringliggande vävnad.

Syftet med projektet är att utforma en behandlingsmetod för cancer i matstrupen
med MR som bildunderlag vid planering av behandling. Vid avbildning av
matstrupen uppstår tekniska utmaningar då både hjärtats aktivitet och
andningsrörelser bidrar till störningar i MR-bilder. Ett MR protokoll har
utarbetas under denna studie och en tumör i matstrupen hos en patient har kunnat
avbildas med tillräckligt god bildkvalité för att kunna användas som underlag för
behandling. (Less)
Please use this url to cite or link to this publication:
author
Reci, Rrezarta
supervisor
organization
course
MSFT01 20151
year
type
H2 - Master's Degree (Two Years)
subject
language
English
id
8147434
date added to LUP
2015-10-30 13:10:30
date last changed
2017-01-09 16:30:58
@misc{8147434,
  abstract     = {Purpose: The aim of this study was to investigate a new methodology for
brachytherapy of oesophageal cancer using magnetic resonance (MR) imaging
for treatment planning. That includes finding a suitable oesophageal applicator
that can be visualised on MR images and to create dose and fraction schedule
that should be used brachytherapy treatments.

Material and Methods: A total of six patients were involved to determine a
suitable MR sequence for visualisation of the oesophageal tumour. The patients
were scanned with two different T2-weighted sequences, inversion recovery fast
spin echo (IR FSE) and fast recovery fast spin echo (FRFSE). The imaging was
performed on a 3.0 T MR scanner from GE Healthcare. Dose planning was
performed on MR images using two different methods. In the first method the
dose was prescribed at 10 mm from the applicator centre, as currently used at
Skåne University Hospital. In the second method the dose planning was
performed by manually adjusting the dwell times until tumour coverage was
reached. An MR safe oesophageal applicator could not be found on the market.
Therefore a duodenal tube was used and modified. Different contrast agents were
studied in order to render the tube visible on MR images.

Results: The oesophageal tumour was successfully visualised and delineated on
T2-weighted images with FRFSE sequences. Furthermore, improved dose
coverage to the tumour was observed when the dose planning was manually
optimised to the tumour volume, where V100% to the tumour was increased from
70% to 95%. Moreover, the applicator was filled with a saline solution and was
visualised on the MR images.

Conclusion: Brachytherapy treatment for oesophageal cancer with MR imaging
provides an improved tumour visualisation and the manifesting of DVH
parameters enables dose coverage to the tumour.},
  author       = {Reci, Rrezarta},
  language     = {eng},
  note         = {Student Paper},
  title        = {High-­dose rate intraluminal brachytherapy for oesophageal cancer using MR imaging: A clinical implementation},
  year         = {2015},
}