Remotely Operated Robotic High Intensity Focused Ultrasound (HIFU) Manipulator System for Critical Systems for Trauma and Transport (CSTAT)

摘要

A need exists to use High Intensity Focused Ultrasound (HIFU) for vessel cauterization in current and future Critical Systems for Trauma and Transport (CSTAT) systems to improve battlefield medicine to save lives. For this purpose, a rugged CSTAT-compatible hemostatic HIFU system was designed that consists of a robotic manipulator, a detachable end-effector containing the HIFU applicator, and a HIFU therapy planning and control strategy. The HIFU applicator is a 23-annuli phased array operating at 2.2 MHz, capable of cauterizing vessels from the skin surface to a depth of 70 mm at in-situ intensities exceeding 1500W/cm{sup}2. It is coupled to a sector con-focal imaging array (8-5 MHz), which uses Doppler technology to detect bleeding, and is capable of acquiring 3D volume images for treatment planning. The applicator is scanned in the XY plane across the skin of the patient by the end-effector under ultrasound guidance to cauterize larger volumes. An off-the-shelf robotic manipulator places (and later retrieves) the end-effector in the appropriate location on the patient. The system is robust against vibration, as the manipulator is only used to place/retrieve the end-effector on the patient. All subsequent treatment activities are performed by the end-effector, which is tightly registered to the treatment volume using suction. Diagnosis, treatment, and treatment monitoring are performed by the end-effector under local or remote control with ultrasound imaging, Doppler, and video feedback during the transport of the injured soldier. Key aspects of the design, including the suction mechanism, Doppler laceration detection, and 3D volume reconstruction were investigated using phantoms, while ultrasound and mechanical simulation tools were used to define the system specifications, the HIFU applicator, the treatment parameters, and the hemostasis control strategy.