High intensity focused ultrasound for treatment of bleeding and air leaks due to lung trauma

Abstract

In thoracic surgery, bleeding and air leaks from the lungs can be difficult to control. We have investigated the use of high intensity focused ultrasound (HIFU) for control of lung bleeding and air leaks in operative situations. An intraoperative HIFU device, equipped with a Titanium coupler, was used. The HIFU transducer was a PZT-8 concave element, with a focal length of 5 cm, and a diameter of 2.5 cm. The transducer was operated at 5.7 MHz and intensity of 5000 W/cm2. The coupler length was 4 cm, placing the focal volume, defined by full-width half-maximum at approximately 1 cm from the tip of the coupler. A pig animal model was used. Incisions in the lung were made, having lengths of 2–5 cm, and depths of 3–10 mm which created both parenchymal hemorrhage and air leakage from the lung. HIFU was applied within 10 seconds of inducing the injury. The average hemostasis time was approximately 60 seconds. All incisions were completely sealed, and no blood or air leaked from the incisions. Intraoperative HIFU may provide an effective method in various pulmonary surgery indications, and hemostasis and control of air leaks from lacerations due to trauma. [Work supported by NIH and NSF.]