Heating efficiency improvement by using a spherically-concaved sectored array in focused ultrasound thermal therapy.

Area of Science:

• Medical physics
• Biomedical engineering
• Acoustic therapies

Background:

• Focus splitting using sector-sectioned phased arrays can increase necrotic volume and reduce treatment time for large tumors.
• Split focus methods suffer from lower energy concentration and focal beam distortion, limiting practical application.
• Current clinical applications face challenges with low heating efficiency in split-focus sonications.

Purpose of the Study:

• To propose and evaluate a new heating strategy combining strongly-focused and split-focused ultrasound patterns.
• To improve heating efficiency for enhanced thermal lesion formation in tissue.
• To overcome limitations of split-focus sonications for efficient tumor treatment.

Main Methods:

• Theoretical predictions of thermal lesion formation.
• Ex-vivo tissue experiments utilizing combined sonication patterns.
• Comparison of heating efficiency between standard and proposed strategies.

Main Results:

• The proposed strategy of combining focused and split-focused patterns significantly increased thermal lesion dimensions.
• Theoretical predictions were validated by ex-vivo experimental results.
• Enhanced heating efficiency was observed with the combined sonication approach.

Conclusions:

• The novel heating strategy effectively enlarges thermal lesions.
• This approach offers a potential solution to the low heating efficiency of split-focus sonications.
• The method may facilitate shorter total treatment times in clinical applications for large tumors.