Related Experiment Videos
Ultrasonic Doppler detection of laser-tissue interaction
C J Hartley1, H Ying, M Motamedi
1Department of Medicine, Baylor College of Medicine, Houston, TX 77030.
Ultrasound in Medicine & Biology
|January 1, 1994
Summary
Monitoring laser-tissue interaction using ultrasound real-time. Ultrasound detects tissue changes from laser energy absorption, differentiating thermal effects from vaporization for precise laser therapy control.
Area of Science:
- Biomedical Engineering
- Medical Physics
Background:
- Precise control of laser energy delivery is crucial for safe and effective laser therapy.
- Monitoring tissue response to laser energy absorption in real-time is challenging.
Purpose of the Study:
- To investigate the use of ultrasound to monitor laser-induced changes in tissue properties.
- To correlate ultrasonic signal changes with laser-tissue interaction levels.
Main Methods:
- A modified 20 MHz pulsed Doppler ultrasound system was used.
- Real-time monitoring of beef liver and muscle exposed to a high-power diode laser in vitro.
- Analysis of acoustic activity, echogenicity, and time to onset of specific ultrasonic events.
Main Results:
- Two distinct types of acoustic activity (Type 1: thermal expansion/contraction; Type 2: vaporization) were observed.
- Increased echogenicity and delayed onset of Type 2 activity correlated with laser power, tissue type, and lesion severity.
- Doppler signal processing differentiated levels of laser-tissue interaction.
Conclusions:
- Laser energy absorption alters tissue acoustic properties during and after exposure.
- Ultrasound monitoring can differentiate thermal effects from tissue vaporization in real-time.
- This technique offers potential for enhanced control and safety in laser therapies.