RF heating-enhanced photoacoustic tomography

Area of Science:

• Biomedical Imaging
• Photoacoustic Tomography
• Thermoacoustic Tomography

Background:

• Photoacoustic tomography (PAT) and thermoacoustic tomography (TAT) use acoustic signals from electromagnetic absorption for noninvasive deep tissue imaging.
• PAT detects optical absorption, while TAT targets radiofrequency (RF) absorption, offering complementary tissue information.
• Integrating PAT and TAT is challenging due to the cost and complexity of RF sources.

Purpose of the Study:

• To demonstrate the integration of PAT with a low-cost RF heater for simultaneous optical and RF absorption imaging.
• To introduce RF Heating-Enhanced Photoacoustic Tomography (HEPAT) as a novel imaging modality.
• To explore HEPAT's potential for enhanced contrast and diagnostic power.

Main Methods:

• Developed a system combining PAT with a low-cost RF heater.
• Utilized RF heating to induce temperature-dependent changes in thermomechanical properties.
• Mapped RF absorption by detecting acoustic signals generated from these changes.
• Imaged both optical and RF absorption in tissue phantoms.

Main Results:

• Successfully integrated a low-cost RF heater with PAT.
• Demonstrated the capability of HEPAT to image both optical and RF absorption.
• Showcased that HEPAT provides distinct, complementary contrast compared to standard PAT.
• Validated the use of inexpensive RF subsystems for imaging RF absorption.

Conclusions:

• HEPAT offers a cost-effective approach to combine optical and RF absorption imaging.
• The novel modality expands specificity and diagnostic power in biomedical imaging.
• HEPAT opens new research avenues for studying temperature-related tissue phenomena.