Diego Felipe Martinez1, Arjama Halder1,2, Will Bradfield Handler1, and Blaine Alexander Chronik1,2
1The xMR Labs, Physics and Astronomy, Western University, London, ON, Canada, 2Medical Biophysics, Western University, London, ON, Canada
1The xMR Labs, Physics and Astronomy, Western University, London, ON, Canada, 2Medical Biophysics, Western University, London, ON, Canada
Cryogen-free low-field MR systems were investigated for heating interactions between the main magnet and the gradient system, as this heating could cause stability issues. Gradient components were tested at various strengths, with heating due to interaction never exceeding 0.015 K.
Figure and Table comparing the temperature increase of the main magnet caused by running a bipolar trapezoidal gradient. The pulse sequence contained 40 cycles of 0.9ms duration bipolar lobes and had a maximum field strength of 71.4 mT/m in the x- and y- axis gradients and a 75.75 mT/m in the z-axis gradient.
Comparison of heating at different gradient strengths. The parameters of the fit are shown in Figure 2. The pulse sequence used in these trials was a single lobe Trapezoidal pulse with a rise time of 0.1ms, total duration of 200ms, and TR of 2000ms.
