Development of MRI methods for experimental disease models

• Main Author: Campbell-Washburn, A. E.
• Published: University College London (University of London) 2012
• Subjects: 610
• Online Access: http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.625958

Magnetic resonance imaging (MRI) is a powerful technique for the in vivo study of experimental disease models. The application of MRI to animal models requires the development of specialized methods which can provide insight into anatomy, function, physiology and specific pathology. This thesis research focused around the development of MRI methods for imaging the mouse heart and other body organs. In this work, single slice arterial spin labelling (ASL) was implemented and optimized for the in vivo measurement of perfusion in the mouse heart. A fast ECG-gated Look-Locker sequence was used for T1 mapping with data logger recordings for the assessment of respiration corruption and additional prospective gating. A variability and repeatability study was performed to assess the applicability of the technique in vivo. This technique was then extended to have multi-slice capabilities through the implementation of a multi-slice cardiac T1 mapping sequence. In order to apply the multi-slice sequence in vivo, a new method of perfusion quantification was developed to compensate for the input function of the blood magnetization. Amyloidosis is a severe condition where amyloidotic fibrils of mis-folded proteins accumulate in the extracellular space. With the development of new therapies, there is an urgent need for sensitive imaging markers for the monitoring of amyloidosis. In this research, the extracellular volume fraction, as measured using equilibrium contrast MRI with primed infusions of gadolinium, was assessed as a marker for the detection of amyloidosis and for the monitoring of amyloid depletion during therapy. Finally, in order to remove spike noise in MRI data sets, a post-processing algorithm was implemented and validated for the removal of RF spikes in k-space Overall, this thesis research presents methodological developments of cardiac and body MRI for the in vivo study of experimental models of disease.