Automated Doppler Ultrasound Imaging of Lower Limb Arteries

Overview

This study presents a robotic system for automatic scanning of the femoral artery using 3D Doppler ultrasound. The system employs X-Plane mode Doppler data at 10 Hz and impedance control to maintain probe contact and track vessel position, validated in a volunteer study with seven participants.

Background

Ultrasound imaging is widely used for vascular diagnostics due to its safety, real-time imaging, and ability to assess blood flow kinetics via Doppler ultrasound. Duplex sonography is the preferred tool for diagnosing and monitoring vascular pathologies, especially peripheral arterial disease, which is increasing in prevalence. However, ultrasound image quality is highly operator-dependent, and sonographers face ergonomic challenges and staffing shortages. Robotic automated ultrasound systems offer potential to standardize imaging, improve reproducibility, and reduce operator burden. Prior robotic systems have been tested mainly on phantoms or carotid arteries, with limited use of Doppler ultrasound in robotic vascular imaging.

Data Highlights

The system uses a 3D ultrasound probe with Doppler X-Plane mode providing 10 Hz data acquisition. Transformations between robot base, flange, probe tip, and ultrasound volume frames are calculated using homogeneous transformation matrices for precise probe positioning. Impedance control ensures safe and consistent probe contact force. The system was validated in a study involving seven volunteers.

Key Findings

• Integration of 3D Doppler ultrasound with robotic arm enables automated tracking of femoral artery position.
• X-Plane Doppler mode at 10 Hz offers enhanced longitudinal vessel visualization compared to 2D imaging.
• Impedance control maintains appropriate probe contact force, ensuring patient safety and image quality.
• Spatial calibration using transformation matrices allows accurate mapping between ultrasound images and robot coordinates.
• The system was successfully validated in a volunteer study, demonstrating feasibility for clinical application.

Clinical Implications

Automated robotic Doppler ultrasound scanning can standardize lower limb artery imaging, reducing operator dependency and improving reproducibility. This technology may alleviate sonographer workload and address staffing shortages while providing reliable vascular assessments critical for peripheral arterial disease management.

Conclusion

The presented robotic system advances automated vascular ultrasound by combining 3D Doppler imaging and compliant robotic control, validated in human volunteers. This approach holds promise for enhancing routine duplex sonography of leg arteries in clinical practice.

References

1. Haxthausen et al. -- Robotic peripheral artery scanning
2. Jiang et al. -- Fully robotic system for tubular structure detection
3. Recent system for automated 3D ultrasound acquisition -- Neural network vessel center detection
4. Volunteer studies on automatic carotid and Doppler US scanning
5. Calibration methods for ultrasound volume transformation