Flexible, high spatial and temporal resolution absolute thermometry of MRI phantoms

Motivation: Quantitative Magnetic Resonance Imaging (qMRI) is becoming popular and is often evaluated in phantoms. However, MRI properties (T1, T2, diffusion, etc.) depend on temperature, so accurate absolute temperature measurements of the phantom is needed. Goal(s): Being able to measure absolute temperature throughout qMRI phantoms in a practical, efficient, and accurate way. Approach: A straight forward spectroscopic imaging approach is used to image ethylene glycol-filled vials and an automatic processing pipeline reconstructs temperatures. Results: Rapid (15 s/slice) and accurate (up to 0.5 °C) absolute temperature measurements are demonstrated at two different 3T scanners. Impact: With the described approach rapid and accurate MRI-based absolute phantom temperature measurements can be acquired in a practical way. This will help researchers developing quantitative measurements of temperature-sensitive parameters such as T1,T2, and diffusion, using phantoms for validation and benchmarking.