Abstract: An image-guide therapy system comprises a thermal treatment device (e.g., an ultrasound transducer) configured for transmitting a therapeutic energy beam, and The system further comprises an imaging device (e.g., a magnetic resonant imaging (MRI) device) configured for acquiring images of the target tissue mass and the thermal treatment device. The system further comprises a controller configured for controlling thermal dose properties of the thermal treatment device to focus the energy beam on a target tissue mass located in an internal body region of a patient, and a processor configured for tracking respective positions of the thermal treatment device and the target tissue mass in a common coordinate system based on the acquired images. The system may optionally comprise a display configured for displaying the acquired images.

Abstract: A method for treating body tissue using acoustic energy includes identifying a target focal zone of tissue to be treated, delivering a first pulse of acoustic energy from a transducer to generate bubbles in a tissue region located distally, relative to the transducer, of a focal center of the target focal zone, and delivering a second pulse of acoustic energy from the transducer in the presence of the bubbles generated by the first pulse, the second pulse focused at the focal center to generate thermal ablation energy. In a further embodiment, a method of treating body tissue using ultrasound energy includes identifying a target focal zone to be treated and delivering a plurality of pulses of acoustic ablation energy to locations distributed symmetrically in or proximate a focal plane about the focal center of the target focal zone.

Abstract: A system for focusing ultrasonic energy through intervening tissue into a target site within a tissue region includes a transducer array including transducer element, an imager for imaging the tissue region, a processor receiving images from the imager to determine boundaries between different tissue types within the intervening tissue and generate correction factors for the transducer elements to compensate for refraction occurring at the boundaries between the tissue types and/or for variations in speed of sound. A controller is coupled to the processor and the transducer array to receive the correction factors and provide excitation signals to the transducer elements based upon the correction factors. The correction factors may include phase and/or amplitude correction factors, and the phases and/or amplitudes of excitation signals provided to the transducer elements may be adjusted based upon the phase correction factors to focus the ultrasonic energy to treat tissue at the target site.

Abstract: A focused ultrasound system includes a transducer array, a controller for providing drive signals to the transducer array, and a switch. The transducer array includes a plurality of “n” transducer elements, and the controller includes a plurality of “m” output channels providing sets of drive signals having respective phase shift values, “m” being less than “n.” The switch is coupled to the output channels of the controller and to the transducer elements, and is configured for connecting the output channels to respective transducer elements. The controller may assign the transducer elements to respective output channels based upon a size and/or shape of a desired focal zone within the target region, to steer or otherwise move a location of the focal zone, and/or to compensate for tissue aberrations caused by tissue between the transducer array and the focal zone, geometric tolerances and/or impedance variations of the transducer elements.

Abstract: A system (10) for treating tissue within a body is configured to deliver a first level of ultrasound energy to a target tissue region (42) for a first duration resulting in the generation of micro-bubbles (56) in the target tissue region, determine one or more characteristics of the target tissue region in the presence of the micro-bubbles, and deliver a second level of ultrasound energy to the target tissue region for a second duration, wherein one or both of the second energy level and the second duration are based, at least in part, on the determined one or more characteristics of the target tissue region.

Abstract: An ultrasound transducer comprises a multiplicity of piezoelectric transducer elements attached to a backing layer and forming a two-dimensional array, the transducer elements each comprising one or more piezoelectric members that collectively form an energy transmitting surface of the respective transducer element, the energy transmitting surface having a geometric center, wherein the respective transducer element geometric centers are in an irregular formation.

Abstract: Method for adjusting the output of a phased array ultrasonic transducer using surface mapping. The transducer surface is mapped using a sensor, such as a hydrophone, to determine the actual location of each transducer element relative to the expected location of each transducer element. Mapping can be performed by measuring a distance between a hydrophone and each transducer element. At least one of the hydrophone and the transducer are moveable relative to each other to map the transducer surface. A determination is made whether the actual location of a transducer element differs from the expected location. Drive signals of certain transducer elements having actual locations that differ from expected locations are adjusted to control the output of the transducer.

Abstract: An image-guide therapy system comprises a thermal treatment device (e.g., an ultrasound transducer) configured for transmitting a therapeutic energy beam, and The system further comprises an imaging device (e.g., a magnetic resonant imaging (MRI) device) configured for acquiring images of the target tissue mass and the thermal treatment device. The system further comprises a controller configured for controlling thermal dose properties of the thermal treatment device to focus the energy beam on a target tissue mass located in an internal body region of a patient, and a processor configured for tracking respective positions of the thermal treatment device and the target tissue mass in a common coordinate system based on the acquired images. The system may optionally comprise a display configured for displaying the acquired images.

Abstract: Transrectal ultrasound probes, systems and related methods. A probe includes an anisotropic balloon that defines a cavity for receiving a probe body that carries an ultrasound transducer. A vent tube is attached to or integral with, an outer surface of the anisotropic balloon. The balloon is structured to have inflation and elasticity characteristics that allow air bubbles between the balloon and rectal wall to be pushed away to form an improved acoustic interface while allowing bowel gas to be vented through the vent tube.

Abstract: Method for adjusting the output of a phased array ultrasonic transducer using surface mapping. The transducer surface is mapped using a sensor, such as a hydrophone, to determine the actual location of each transducer element relative to the expected location of each transducer element. Mapping can be performed by measuring a distance between a hydrophone and each transducer element. At least one of the hydrophone and the transducer are moveable relative to each other to map the transducer surface. A determination is made whether the actual location of a transducer element differs from the expected location. Drive signals of certain transducer elements having actual locations that differ from expected locations are adjusted to control the output of the transducer.

Abstract: An ultrasound coupling device for acoustically coupling an ultrasound transducer with a patient's body comprises a fluid chamber having an ultrasound transducer interface for placing an ultrasound transducer in contact with water within said fluid chamber. The coupling device also has a patient interface comprising a water permeable membrane. The membrane has an internal membrane surface which is in contact with the water in the water tank and an external membrane surface can be placed in contact with the patient's body. The membrane is specially designed to allow water from inside the water tank to slowly permeate or “leak” to the external membrane surface while such surface is in contact or placed in very close proximity to the patient's skin. The slow permeation rate maintains the external membrane surface wet and free of air bubbles during a procedure which can take several hours. At the same time, the slow rate of permeation does not cause any water spillage around the patient.

Abstract: An ultrasound transducer comprises a multiplicity of piezoelectric transducer elements attached to a backing layer and forming a two-dimensional array, the transducer elements each comprising one or more piezoelectric members that collectively form an energy transmitting surface of the respective transducer element, the energy transmitting surface having a geometric center, wherein the respective transducer element geometric centers are in an irregular formation.

Abstract: A system and method for using magnetic resonance to track a medical device which attenuates interfering MR signals. The system comprises an MR tracking device comprising one or more radiofrequency (RF) tracking coils adapted to receive a magnetic resonance MR response signal from nuclei excited by an RF pulse. Ideally, the RF tracking coil only receives an MR response signal from nuclei in matter in the close vicinity of the tracking device. The tracking device is attached to medical device. The interfering signal tends to emanate from large objects or large volumes that are outside the close vicinity of the tracking device but which are still weakly coupled to the tracking device. A dephasing gradient is applied perpendicular to the readout gradient before the RF response signal is received thereby dephasing the interfering signal emanating from remote nuclei, which strongly attenuates the interfering signal while the MR response signal is substantially unaffected.

Abstract: A focused ultrasound system comprises a transducer having a multiplicity of transducer elements, drive circuitry that generates and outputs a plurality of drive signals, each offset by a respective phase difference, and a controller for selectively coupling the drive signals to respective transducer elements, the controller including a plurality of first tier switching modules and second tier switching modules. Each first tier module receives as an input the plurality of drive signals and outputs one of the drive signals in response to a drive signal selection signal. Each second tier module is coupled to a respective grouping of transducer elements and selectively couples a respective selected drive signal output from a first tier switching module to one or more of the transducer elements in response to a transducer element selection signal.

Abstract: Systems and methods are provided for positioning a therapy device, such as an ultrasound transducer, using a tilt sensor carried by the transducer and a positioner coupled to the transducer. The positioner provides roll and pitch control as well as translating the transducer in lateral and longitudinal directions. A processor receives signals from the tilt sensor corresponding to the actual rotational orientation of the transducer and controls the positioner to adjust the orientation of the therapy device until a desired position is achieved.