Water immersion ultrasound can improve the repeatability of ultrasonic measurement of dorsalis pedis artery diameter and hemodynamic parameters.

Objective: In comparing the repeatability of the internal diameter and hemodynamic parameters of the dorsalis pedis artery measured by immersion ultrasound and contact ultrasound, the factors affecting the accuracy and repeatability of measurement were analyzed. This study aimed to provide a better method for ultrasound evaluation of the dorsalis pedis artery before flap transplantation.

Methods: Two senior sonographers measured the diameter of the dorsalis pedis artery (D) of 56 healthy volunteers, measuring at the same location and at different time points using water immersion and contact ultrasound. Color Doppler ultrasound was used to measure the hemodynamics of the dorsalis pedis artery, including peak systolic velocity (PSV), end diastolic velocity (EDV), and resistance index (RI). The interclass correlation coefficient (ICC) was used to evaluate the intraobserver and interobserver repeatability for each group's measurements.

Results: The intraobserver and interobserver reproducibility of D, PSV, EDV, and RI measurements by water immersion ultrasound was very good. The intraobserver and interobserver reproducibility of the contact ultrasound measurements of D, PSV, EDV, and RI was good.

Conclusion: The repeatability of water immersion ultrasound is better than that of contact ultrasound in the measurement of the dorsalis pedis artery. Water immersion ultrasound can improve the near-field resolution of superficial tissues and increase the display of the lengths of blood vessels in images, thereby suggesting its superiority in ultrasound examination of dorsalis pedis arteries.