Uniform Heating during Focused Ultrasound Thermal Therapy

The focal spot of a high intensity focused ultrasound transducer is small. To heat a large target volume, multiple treatment spots are required. If the power of each treatment spot is fixed, it could results in insufficient heating of initial spots and over-heating of later ones, which is caused by the thermal diffusion. Hence, to produce a uniform heated volume, the delivered energy of each treatment spot should be properly adjusted. In this study, we proposed an iterative, extrapolation technique to adjust the required ultrasound energy of each treatment spot. Three different scanning pathways were used to evaluate the performance of this technique. Results indicate that by using the proposed technique, uniform heating volume could be obtained.

Authors:

• To-Yuan Chen
• Tzu-Ching Shih
• Hao-Li Liu
• Kuen-Cheng Ju

Keywords:

• focused ultrasound
• thermal therapy
• uniform heating
• iteration
• extrapolation
• scan

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