Simultaneous T₁ measurements and proton resonance frequency shift based thermometry using variable flip angles

Abstract

A method is presented which allows precise temperature and longitudinal (T 1 ) relaxation time measurements with high spatial and temporal resolution. This is achieved by combining dynamic variable flip angle based T 1 relaxation mapping with proton resonance frequency shift based thermometry. Herein, dynamic T 1 mapping is either used as a complementary measure of temperature or for the detection of T 1 contrast agent release. For the first application, the temperature evolution during a high-intensity focused ultrasound tissue ablation experiment was measured in both, porcine fat and muscle, simultaneously. In this application, temperature accuracies of 2.5 K for

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Thermosensitive liposomal drug delivery systems: state of the art review

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