University of Washington

Other

Mirabilis Medica, Inc.

Stephen J Carter

Roy W Martin

Lawrence A Crum

Shahram Vaezy

George W Keilman

George Woodrow Keilman

Peter John Kaczkowski

Andrew Hollis Proctor

Michael Gaps

W Scott Helton

Victor Y Fujimoto

A noninvasive technique that can be used to deny blood flow to a particular region of tissue, without the inherent risks associated with invasive procedures such as surgery and minimally-invasive procedures such as embolization. Blood flow in selected portions of the vasculature can be occluded by selectively treating specific portions of the vasculature with high intensity focused ultrasound (HIFU). The occlusion denies undesired tissue the nutrients and oxygen provided by blood flow, causing necrosis in the undesired tissue. An imaging technology (such as magnetic resonance imaging, magnetic resonance angiography, ultrasound imaging, Doppler based ultrasound imaging, or computed tomographic angiography) is used to identify the undesired tissue, and the vascular structures associated with the undesired tissue. A portion of the vasculature providing blood flow to the undesired tissue is selected, and HIFU is administered to the selected portion of the vasculature to occlude blood flow through that portion of the vasculature.

Treatment of unwanted tissue by the selective destruction of vasculature providing nutrients to the tissue

Ultrasound contrast agents are used to enhance imaging and facilitate HIFU therapy in four different ways. A contrast agent is used: (1) before therapy to locate specific vascular structures for treatment; (2) to determine the focal point of a HIFU therapy transducer while the HIFU therapy transducer is operated at a relatively low power level, so that non-target tissue is not damaged as the HIFU is transducer is properly focused at the target location; (3) to provide a positive feedback mechanism by causing cavitation that generates heat, reducing the level of HIFU energy administered for therapy compared to that required when a contrast agent is not used; and, (4) to shield non-target tissue from damage, by blocking the HIFU energy. Various combinations of these techniques can also be employed in a single therapeutic implementation.

Use of contrast agents to increase the effectiveness of high intensity focused ultrasound therapy

Method and apparatus for the simultaneous use of ultrasound on a probe for imaging and therapeutic purposes. The probe limits the effects of undesirable interference noise in a display by synchronizing high intensity focused ultrasound (HIFU) waves with an imaging transducer to cause the noise to be displayed in an area of the image that does not overlap the treatment site. In one embodiment, the HIFU is first energized at a low power level that does not cause tissue damage, so that the focal point of the HIFU can be identified by a change in the echogenicity of the tissue caused by the HIFU. Once the focal point is properly targeted on a desired treatment site, the power level is increased to a therapeutic level. The location of each treatment site is stored and displayed to the user to enable a plurality of spaced-apart treatment sites to be achieved. As the treatment progresses, any changes in the treatment site can be seen in the real time, noise-free image. A preferred application of the HIFU waves is to cause lesions in blood vessels, so that the supply of nutrients and oxygen to a region, such as a tumor, is interrupted. The tumor will thus eventually be destroyed. In a preferred embodiment, the HIFU is used to treat disorders of the female reproductive system, such as uterine fibroids. The HIFU treatment can be repeated at spaced-apart intervals, until any remaining fibroid tissue is destroyed.

Ultrasound therapy head configured to couple to an ultrasound imaging probe to facilitate contemporaneous imaging using low intensity ultrasound and treatment using high intensity focused ultrasound

Methods and apparatus for enabling substantially bloodless surgery and for stemming hemorrhaging. High intensity focused ultrasound (&ldquo;HIFU&rdquo;) is used to form cauterized tissue regions prior to surgical incision, for example, forming a cauterized tissue shell around a tumor to be removed. The procedure is referred to as &ldquo;presurgical volume cauterization.&rdquo; In one embodiment, the method is particularly effective for use in surgical lesion removal or resection of tissue having a highly vascularized constitution, such as the liver or spleen, and thus a propensity for hemorrhaging. In further embodiments, methods and apparatus for hemostasis using HIFU is useful in both surgical, presurgical, and medical emergency situations. In an apparatus embodiment, a telescoping, acoustic coupler is provided such that depth of focus of the HIFU energy is controllable. In other embodiments, apparatus characterized by portability are demonstrated, useful for emergency medical situations.

Method and apparatus for medical procedures using high-intensity focused ultrasound

Noise-free real time ultrasonic imaging of a treatment site undergoing high intensity focused ultrasound therapy

Methods and apparatus for enabling substantially bloodless surgery and for stemming hemorrhaging. High intensity focused ultrasound ('HIFU') is used to form cauterized tissue regions prior to surgical incision, for example, forming a cauterized tissue shell around a tumor to be removed. The procedure is referred to as 'presurgical volume cauterization.' In one embodiment, the method is particularly effective for use in surgical lesion removal or resection of tissue having a highly vascularized constitution, such as the liver or spleen, and thus a propensity for hemorrhaging. In further embodiments, methods and apparatus for hemostasis using HIFU is useful in both surgical, presurgical, and medical emergency situations. In an apparatus embodiment, a telescoping, acoustic coupler is provided such that depth of focus of the HIFU energy is controllable. In other embodiments, apparatus characterized by portability are demonstrated, useful for emergency medical situations.

Method and apparatus for medical procedures using high-intensity focused

Growing community of inventors

La Conner, WA, United States of America

Stephen J Carter