Magnetic Resonance Imaging in Radiotherapy Group
Dr Andreas Wetscherek's group are developing new MRI techniques for radiotherapy with particular application to the UK's first MR-Linac machine.
We develop MRI techniques that enable novel MR-guided radiotherapy workflows.
Background
Radiotherapy has been instrumental in the treatment of cancer for more than 100 years. Treatment is delivered over several fractions to improve tumour control and minimise normal tissue complications. Radiotherapy treatments are planned using electron density information obtained from computed tomography (CT) images to deliver the prescribed dose to the tumour while minimising dose to normal tissue.
Imaging biomarkers that could assess and predict response to treatment are of particular interest, for example to identify resistant subvolumes of the tumour or early signs of side-effects of radiation. MR-guided radiotherapy on a hybrid MR-Linac system enables novel treatment workflows but requires imaging solutions that are different from diagnostic MRI. Our research focuses on two key applications: Functional MRI to assess and predict response to therapy and 4D MRI to manage motion.
Functional MRI
To assess response to treatment, techniques based on diffusion-weighted MRI are particularly promising due to their association with response-related metrics, such as cellularity and cell membrane permeability. Our research interest here is to minimise geometric distortions in diffusion-weighted MRI for use in daily adaptive MR-guided radiotherapy and to enable the simultaneous characterisation of perfusion and diffusion using flow-compensated intravoxel incoherent motion (IVIM) imaging.
In MR-guided radiotherapy with MeV photons, the formation of reactive oxygen species plays an important role in the DNA damage mechanisms and reduced oxygenation (hypoxia) in the tumour is associated with resistance to radiotherapy. We’re working on fast MR relaxometry techniques including MR fingerprinting to perform dynamic T2* and T1 measurements and plan to combine these with oxygen-enhanced MRI to detect tumour hypoxia.
4D MRI
The excellent soft tissue contrast of MRI and the availability of MR imaging at the time of treatment minimises uncertainty about the position and extent of tumours and dose-sensitive organs-at-risk. This real-time information could be used to reduce the risk of radiation-induced side effects or to overcome resistance by boosting the dose to the tumour. Fully leveraging the potential of MR-guided radiotherapy requires replanning treatments using synthetic CT derived from MR images acquired a few minutes before treatment start. 4D MRI aims to characterise physiological motion including respiratory, cardiac and peristaltic motion to derive the correct treatment margins and to enable spatial mapping of the delivered radiation dose.
Following on from our previous work on 4D MRI for radiotherapy, we’re currently working on synthetic 4D-CT for the treatment of lung cancer patients. Together with Prof. Wayne Luk’s team at Imperial College London we are accelerating 4D MR image reconstruction and we are working towards volumetric real-time imaging on the MR-Linac system.
Dr Andreas Wetscherek
Group Leader:
Radiotherapy Physics Modelling, Magnetic Resonance Imaging in Radiotherapy
Dr Andreas Wetscherek's research is focused on developing magnetic resonance imaging techniques for radiotherapy with particular application to the UK’s first MR-Linac machine.
Researchers in this group
.
Phone: +44 20 8722 4436
Email: [email protected]
I am a Postdoctoral Training Fellow working on implementing latest MR image reconstruction techniques to develop fast volumetric imaging for MR Linac. Specifically, the focus of the project is the fast mapping of relaxation parameters to characterise hypoxia in tumours to determine their resistance to radiotherapy treatment.
.
Email: [email protected]
Location: Sutton
I work on imaging techniques to facilitate new applications in MRI-guided radiotherapy of lung cancer. My PhD project’s focus is on the generation of high-fidelity synthetic CT images from data acquired on the ICR’s MR-Linac. These images will provide the means to re-optimise radiation placement minutes before treatment begins.
.
I am a PhD student working on accelerating magnetic resonance imaging to improve radiotherapy treatment on the MR-Linac. My project aims at reconstructing volumetric images from the scanner in real-time to enable the radiotherapy treatment to compensate for respiratory motion when delivering the radiation.
.
I am a Postdoctoral Training Fellow working on distortion-less diffusion-weighted MRI for the Unity MR-Linac system. Another research interest to me is characterization of intravoxel incoherent motion with tailored diffusion-weighting gradient profiles. To achieve this, I use MR pulse programming, which I learned during my PhD on MR Neurography.
Dr Andreas Wetscherek's group have written 68 publications
Most recent new publication 10/2024
See all their publicationsRecent discoveries from this group
