MR thermometry.

Area of Science:

• Biomedical Engineering
• Medical Imaging
• Thermal Therapy

Background:

• Minimally invasive thermal therapy is gaining traction for treating various diseases.
• Accurate temperature monitoring is crucial for ensuring the safety and effectiveness of thermal treatments.
• Noninvasive methods are preferred for real-time temperature assessment during procedures.

Purpose of the Study:

• To review principles of noninvasive temperature measurement using magnetic resonance (MR) imaging.
• To discuss the utility of various MR-based methods for monitoring in vivo thermal therapies.
• To highlight advancements in MR techniques for real-time, artifact-reduced temperature monitoring.

Main Methods:

• Review of MR imaging techniques sensitive to temperature changes.
• Discussion of parameters including proton resonance frequency (PRF), diffusion coefficient (D), T1/T2 relaxation times, and contrast agents.
• Focus on PRF-based phase mapping and accelerated MR imaging for real-time monitoring, including artifact reduction strategies.

Main Results:

• Several MR parameters can be used for noninvasive temperature monitoring.
• PRF-based phase mapping demonstrates excellent linearity, temperature dependence, and tissue independence, making it ideal for in vivo applications.
• Accelerated imaging and motion artifact reduction techniques enhance real-time monitoring capabilities.

Conclusions:

• Noninvasive MR-based temperature monitoring is feasible and essential for thermal therapies.
• PRF phase mapping is a preferred method for its accuracy and reliability in vivo.
• Continued development of accelerated MR techniques and artifact reduction is vital for clinical translation.