Ultrasonic Thermal Monitoring of the Brain Using Golay-Coded Excitations-Feasibility Study.
Summary
This study introduces a new noninvasive method for brain temperature monitoring using focused ultrasound (FUS) transducers. Golay-coded excitations (CoE) show promise for accurate thermal monitoring during FUS procedures.
Area of Science:
- Biomedical Engineering
- Acoustic Imaging
- Thermal Monitoring
Background:
- Magnetic Resonance Imaging (MRI) is the standard for thermal monitoring during focused ultrasound (FUS) transcranial procedures.
- Transcranial ultrasonic thermal monitoring offers a promising alternative.
- Utilizing the therapeutic FUS transducer for thermal monitoring is highly desirable but faces challenges from skull-induced signal interference.
Purpose of the Study:
- To investigate the feasibility of Golay-coded excitations (CoE) for noninvasive temperature monitoring in brain tissue using therapeutic FUS transducers.
- To assess the accuracy of this method in bovine brain samples under hyperthermia conditions.
Main Methods:
- Computer simulations, water phantoms, and ex vivo bovine brain samples were used.
- A 1-MHz therapeutic FUS system with Golay CoE was employed for sonication and data acquisition.
- Calibration curves correlating time-of-flight (TOF) changes with temperature were generated, and measurements were validated against thermocouple data.
Main Results:
- Simulations indicated improved signal-to-noise ratio (SNR) with 4-bit Golay sequences.
- Experimental measurements with bovine bone showed good temperature estimation accuracy.
- Average absolute errors were 1.46 °C ± 1.22 °C for water phantoms and 1.23 °C ± 0.99 °C for brain samples.
Conclusions:
- A novel noninvasive ultrasonic thermal monitoring method using Golay CoE and therapeutic FUS transducers was successfully introduced.
- This technique holds potential for developing acoustic tools for brain thermal monitoring, overcoming skull-related signal challenges.
