Method and system for ultrasound induced hyperthermia with microwave thermometry feedback

An ultrasound hyperthermia system comprising:

• a controllable ultrasound energy source producing ultrasonic energy at a predefined frequency in a range of 0.5-5.0 Megahertz (MHz) and a predefined intensity in a range of 0.1-3.0 Watts per cubic centimeter (W/cm2), the ultrasonic energy inducing heating of a tissue at a target site to bring the tissue to a predefined temperature, the ultrasonic energy inducing the heating remotely from a source external surface of the controllable ultrasound energy source, a focal distance separating the source external surface and the target site, the controllable ultrasound energy source including
• an ultrasound generator configured to generate a low intensity ultrasound signal in a form of an arbitrary ultrasound waveform, the low intensity ultrasound signal inducing hyperthermia in the tissue for a treatment duration, the arbitrary ultrasound waveform having an adjustable amplitude at the predefined frequency,
• an amplifier communicatively coupled with the ultrasound generator and configured to amplify the ultrasound signal into an amplified ultrasound signal,
• an impedance matching network communicatively with the amplifier and configured to match capacitive loads of the amplified ultrasound signal for maximizing power transfer through the ultrasound hyperthermia system, and
• a piezoelectric ultrasound transducer communicatively coupled to the ultrasound generator via the impedance matching network, the piezoelectric ultrasound transducer producing the ultrasonic energy based on the amplified ultrasound signal;
• a water-filled cone coupling the piezoelectric ultrasound transducer, via a sterile membrane, to the tissue, the water-filled cone including recirculated and degassed chilled water, the water-filled cone focusing the ultrasonic energy to heat the tissue;
• a microwave radiometer for passively determining temperature of the tissue via received microwaves, the microwave radiometer having a radiometer external surface that is in contact with the target site, the microwave radiometer including
• a microwave antenna for detecting a microwave signal caused by the ultrasonic energy heating the tissue, the microwave antenna attached confocally to the controllable ultrasound energy source,
• an internal calibrated temperature source configured to determine an absolute temperature, and
• a Radio Frequency (RF) switch communicatively coupled with the microwave antenna and the internal calibrated temperature source, the RF switch being configured to detect, based on the microwave signal, a tissue temperature relative to the absolute temperature,
• a local oscillator configured to produce a baseband signal in a range of 1-6 Gigahertz (GHz),
• a Radio Frequency (RF) mixer communicatively coupled with the RF switch and the local oscillator, the RF mixer being configured to filter and mix down background noise in the microwave signal,
• a digital signal processor communicatively coupled with the RF mixer and RF switch, the digital signal processor configured to
• integrate the baseband signal for a period of time to determine a baseband energy of the microwave signal,
• determine an actual temperature by comparing the absolute temperature with the tissue temperature,
• feed back the actual temperature to the ultrasound generator, and
• adjust the predefined frequency and the predefined intensity from initial values to adjusted values within a respective ranges.