Self-contained diffuse optical imaging system for real-time detection and localization of vascular occlusions

Area of Science:

• Biomedical Engineering
• Surgical Monitoring
• Medical Imaging

Background:

• Free flap surgery transfers tissue but risks vascular occlusion.
• Prompt detection of vascular occlusions is crucial to prevent flap necrosis.
• Current monitoring methods may not provide continuous, detailed perfusion data.

Purpose of the Study:

• To develop and validate a skin-contact diffusion optical imaging (DOI) system for real-time, 3D flap oxygenation monitoring.
• To enable early detection and localization of vascular occlusions during and after free flap surgery.
• To assess the feasibility of a wearable patch for prolonged perfusion monitoring.

Main Methods:

• A self-contained optical sensor with near-infrared LEDs and photodetectors was designed.
• The system measures concentration changes of oxygenated (HbO) and deoxygenated hemoglobin (HbR).
• A time-efficient algorithm reconstructs 3D oxygenation maps from sensor data, validated with flap models and forearm tests.

Main Results:

• The DOI system provides a 3D representation of flap oxygenation.
• It can detect and localize changes in blood perfusion.
• Preliminary tests demonstrated feasibility for monitoring simulated arterial and venous occlusions.

Conclusions:

• The developed DOI system offers a promising tool for continuous, non-invasive perfusion monitoring in free flap surgery.
• Early detection of vascular compromise is achievable with this wearable technology.
• This system has the potential to improve patient outcomes by facilitating timely corrective actions.