Improving the Temperature Accuracy of Referenceless MR Thermometry in the Presense of Susceptibility Artifact

Mengyue He¹, Chao Zou¹, Changjun Tie¹, Wensha Guo¹, Yiu-Cho Chung¹, Xin Liu¹

In referenceless MR thermometry, large susceptibility change can affect polynomial model fitting and result in large temperature error. Here, we propose a method to improve the accuracy of referenceless method by excluding the regions with large susceptibility artifact automatically based on the local field map derived from the projection onto dipole fields (PDF) method. Phantom and ex-vivo bovine liver study showed that the method can estimate the baseline image with an error of less than 3oC even when the ROR is corrupted by large susceptibility artifact. The method will be very useful in real time monitoring of temperature changes.