High-intensity therapeutic ultrasound hemostasis system for partial nephrectomy

A partial nephrectomy, a surgery that preserves renal function, is desired for patients with small renal tumors. The system described in this paper applies high-intensity therapeutic ultrasound to obtain coagulation necroses of the renal blood vessels and hence protect the incised kidney from bleeding. The paper provides a brief description of the design and construction of the transducers, as well as presents the results of the acoustic characterization, dosimetry studies in tissue mimicking phantoms and dosimetry studies in ex vivo tissue. With optimum acoustic parameters, approximately 95% ablation was achieved during an in vivo perfused kidney study and the bleeding rate was decreased by 93%. The result suggests that the system can be used to control rapid bleeding; however, to achieve complete hemostasis consistently, more studies need to be conducted.