Comparison of two laser Doppler flowmetry systems for bone blood flow analysis

Area of Science:

• Biomedical Engineering
• Physiology
• Surgical Research

Background:

• Laser Doppler flowmetry (LDF) offers real-time monitoring of capillary perfusion.
• Assessing bone blood flow is crucial for experimental and clinical applications.
• Two LDF systems, LD 5000 and Periflux 2, utilize different Doppler-shift processing mechanisms.

Purpose of the Study:

• To compare the accuracy and ease of use of two commercial LDF systems.
• To evaluate LDF's effectiveness in measuring both cancellous and cortical bone blood flow.
• To validate LDF measurements against the gold standard microsphere technique.

Main Methods:

• Bone blood flow was measured in a sheep model using LD 5000 and Periflux 2 LDF systems.
• Measurements were compared with bone blood flow estimates obtained via 85Sr-labeled microsphere injection.
• LDF readings were repeated after femoral artery occlusion, with a subsequent 46Sc microsphere injection.

Main Results:

• The LD 5000 demonstrated high correlation with microsphere values in two of three sheep.
• The Periflux 2 showed poor correlation in animals with vasomotor instability due to its motion sensitivity.
• The LD 5000 provided more reliable bone blood flow measurements compared to Periflux 2.

Conclusions:

• The LD 5000 is a more accurate and reliable LDF system for assessing bone blood flow compared to the Periflux 2.
• Vasomotor instability can significantly impact the accuracy of motion-sensitive LDF devices.
• LDF technology holds promise for experimental and clinical bone blood flow assessment.