High-range-resolution imaging using frequency domain interferometry with stabilization techniques for real-time vascular ultrasound

In the present study, we employed two techniques to acquire high-range-resolution images of human carotid arteries in vivo using frequency domain interferometry and the Capon method. One technique ensures the robust depiction of artery interfaces; the other suppresses the deterioration of the imaging performance due to variation of the echo waveform. We applied the proposed method to raw data obtained using a commercial ultrasonographic device with a 7.5MHz linear array probe. Our method succeeded to depict a horizontal 0.15-mm-thick agar membrane stably, and the standard deviation of the estimated depth was suppressed to 26.7% of that obtained using the conventional method. Our method also succeeded in acquiring high-range-resolution images of six human carotid arteries in vivo. Requiring 0.06 s on a desktop PC with a single CPU for a 1 × 2 cm region of interest, our method is suitable for real-time imaging.