Quantitative magnetic resonance imaging of the prostate at 7 tesla

点击翻译按钮获取中文摘要

Studentship strategic priority area:Medical Physics Keywords:Prostate, MRI, 7T, RF coilsThis PhD project will be linked to a major new initiative funded by UKRI,who are providing £38m to develop the Precision Medicine Living Lab centred around the Queen Elizabeth University Hospital.The Living Lab aims to integrate medical research across a wide range of disciplines,improving patient outcomes & promoting innovation that will benefit the local economy.The programme includes technology development in clinical MRI at the Imaging Centre of Excellence (ICE), which opened in 2017 to house one of the first 7T MRI scanners installed in a clinical setting.The PhD project will focus on the development & application of 7T MRI for prostate cancer,working in conjunction with Living Lab partners from MR CoilTech,Siemens Healthcare & the NHS.MRI is a valuable tool for the diagnosis of prostate cancer & for monitoring treatment response.Current radiological practice relies on a qualitative visual assessment of images but there is an increasing use of quantitative methods [1] that map diffusion coefficients & relaxation times,or analyse tumour shape & texture.Currently,prostate MRI examinations are performed at a magnetic-field strength of 1.5T or 3T.Recent developments have seen the introduction of 7T MRI scanners into clinical settings.These systems provide a higher signal-to-noise ratio (SNR) [2],which enables an increased spatial resolution & generates more precise parameter estimates.These benefits provide the potential for histopathological features of the prostate to be identified in vivo [3] & for an improved diagnostic accuracy to stage T2 versus T3 tumours at the time of radical prostatectomy.However,MRI at 7T faces the challenge of a reduced electromagnetic wavelength in tissue,which leads to inhomogeneity in the radiofrequency (RF) transmit field and a poor image uniformity.This limitation can be overcome by using parallel-transmit (pTx) methods [4] in which multiple RF channels are used with dedicated pulse waveforms to create a spatially uniform transmit field.The development of pTx technology is a key requirement for clinical MRI at 7T & this will be one of the topics addressed by academic & industry partners within the Living Lab programme.This work is planned for a number of anatomical regions,including the prostate,which will be the specific focus of the proposed PhD project.In addition to the development of MRI acquisition techniques, the Living Lab initiative will also provide funding to start a medical image processing group, which will develop dedicated data-processing and visualisation tools for 7T MRI scans.These tools will be used within the PhD project to provide reliable quantitative parameter maps of the prostate that can be integrated into a wider programme of precision medicine for prostate cancer.The aim of the PhD project will be to develop quantitative MRI of the prostate at 7T to support a precision-medicine approach to the clinical management of prostate cancer.This will be achieved as a series of sub-projects with the following objectives respectively:(1)design & construction of a multi-channel RF transmit coil using a commercial software package for electromagnetic simulation;(2)coil testing for technical performance & safety;(3)optimisation of in-house pTx pulse sequences & image-processing protocols in healthy subjects & patients; &(4) preliminary clinical study to compare with standard methods.With reference to the sub-projects listed above,the student will receive training in the following areas:(1)practical skills in electrical engineering and computer modelling,theoretical knowledge of RF electronics and electromagnetism;(2)experimental design & data analysis,safety considerations in MRI,device testing in medical physics;(3)MRI pulse-sequence development,MRI physics,image reconstruction ?ocessing,scientific programming;(4)clinical-study design,medical statistics,clinical aspects of prostate MRI.