Pedal Arch Blood Flow Acceleration Sensors for Reliable PAD Diagnosis

The patent replaces traditional mechanical pressure-based measurement systems (ABI/TBI using blood pressure cuffs and manual or automated sphygmomanometers) with optical detection systems. Specifically, it uses photoplethysmography (PPG) sensors that detect blood flow changes through light absorption and scattering properties, and continuous wave Doppler ultrasound that measures blood flow velocity. This substitution eliminates the mechanical compression and pressure measurement limitations that cause unreliable readings in diabetic patients with calcified arteries.

The patent fundamentally changes the measurement parameter from blood pressure (mechanical force) to blood flow characteristics (optical and acoustic properties). Instead of measuring systolic and diastolic pressures divided by brachial pressure to get ABI/TBI ratios, the system measures blood flow acceleration time, peak flow velocity, and flow waveform characteristics. These flow parameters remain reliable even when pressure measurements fail due to arterial stiffness or occlusion.

The patent implements continuous blood flow monitoring using photoplethysmography sensors that continuously detect pulsatile blood flow changes, and continuous wave Doppler that continuously measures flow velocity. This provides uninterrupted real-time data on blood flow acceleration, peak flow, and flow cessation timing, enabling dynamic assessment during surgical procedures rather than discrete intermittent pressure measurements.

The system provides immediate real-time feedback on blood flow status by continuously displaying flow waveforms and acceleration time measurements. During surgical revascularization procedures, this allows surgeons to immediately assess whether blood flow has been successfully restored to the foot, enabling intraoperative decision-making without waiting for postoperative pressure measurements.