An image guided catheter navigation system for navigating a region of a patient includes an imaging device, a tracking device, a controller, and a display. The imaging device generates images of the region of the patient. The tracking device tracks the location of the catheter in the region of the patient. The controller superimposes an icon representing the catheter onto the images generated from the imaging device based upon the location of the catheter. The display displays the image of the region with the catheter superimposed onto the image at the current location of the catheter.

Navigation system for cardiac therapies

Surgical devices for treating tissue are provided. Also provided are systems for treating tissue and methods of treating tissue. An exemplary surgical device has a handle, a fluid passage connectable to a fluid source, a tip portion and a distal end. The tip portion can simultaneously provide RF power and conductive fluid to tissue. The tip portion includes an electrode having a domed portion having a domed surface and a cylindrical portion having a cylindrical surface. The domed portion is located distal to the cylindrical portion and occupies at least a portion of the distal end of the surgical device. The device includes a fluid outlet opening in fluid communication with the fluid passage, the fluid outlet opening configured to provide the conductive fluid to a surface of the electrode proximal to the distal end surface of the surgical device.

Fluid-assisted medical devices, systems and methods

An ablation apparatus including a maneuvering mechanism, a conductive element attached to the apparatus, a sensor attached to the apparatus and an output device in communication with the sensor is provided. The sensor senses vibration during the ablation procedure and sends a signal to the output device to reduce power to the conductive element.

Vibration sensitive ablation device and method

The present invention provides an apparatus and a method for producing a virtual electrode within or upon a tissue to be treated with radio frequency alternating electric current, such tissues including but not limited to liver, lung, cardiac, prostate, breast, and vascular tissues and neoplasms. An apparatus in accord with the present invention includes a supply of a conductive or electrolytic fluid to be provided to the patient, an alternating current generator, and a processor for creating, maintaining, and controlling the ablation process by the interstitial or surficial delivery of the fluid to a tissue and the delivery of electric power to the tissue via the virtual electrode. A method in accord with the present invention includes delivering a conductive fluid to a predetermined tissue ablation site for a predetermined time period, applying a predetermined power level of radio frequency current to the tissue, monitoring at least one of several parameters, and adjusting either the applied power and/or the fluid flow in response to the measured parameters.

Apparatus and method for creating, maintaining, and controlling a virtual electrode used for the ablation of tissue

A surgical navigation system for navigating a region of a patient includes a non-invasive dynamic reference frame and/or fiducial marker, sensor tipped instruments, and isolator circuits. The dynamic reference frame may be repeatably placed on the patient in a precise location for guiding the instruments. The instruments may be precisely guided by positioning sensors near moveable portions of the instruments. Electrical sources may be electrically isolated from the patient.

Method and apparatus for surgical navigation

The effect of temperature and thermal dose (equivalent minutes at 43 °C) on ultrasonic attenuation in fresh dog muscle, liver, and kidney in vitro, was studied over a temperature range from room temperature to 70 °C. The effect of temperature on ultrasonic absorption in muscle was also studied. The attenuation experiments were performed at 4.32 MHz, and the absorption experiments at 4 MHz. Attenuation and absorption increased at temperatures higher than 50 °C, and eventually reached a maximum at 65 °C. The rate of change of tissue attenuation as a function of temperature was between 0.239 and 0.291 Np m−1 MHz−1 °C−1 over the temperature range 50–65 °C. A change in attenuation and absorption was observed at thermal doses of 100–1000 min, where a doubling of these loss coefficients was observed over that measured at 37 °C, presumably the result of changes in tissue composition. The maximum attenuation or absorption was reached at thermal dosages on the order of 107 min. It was found that the rate at which t...

Dependence of ultrasonic attenuation and absorption in dog soft tissues on temperature and thermal dose

A transducer assembly for visualization and treatment of transcutaneous and intraoperative sites includes in combination a visualization transducer and a treatment transducer, each of which are movable with both linear and rotary degrees of freedom. Movement of each transducer is by various motor and geared drive arrangements wherein certain degrees of freedom for one transducer are separate and independent from the degrees of freedom for the other transducer. At least one degree of freedom for each transducer is common and the transducers are moved concurrently. One arrangement of the transducer combination is for prostate treatment and includes a specific shape and configuration for anatomical considerations and a control unit which is operable external to the patient to control both transducers and a reflective scanner which are inserted into the patient as part of the ultrasound probe.

Localization and therapy system for treatment of spatially oriented focal disease

An ultrasound brain lesioning system with ultrasound, CT or MRI site localization includes a skull fixation apparatus (13), a position data translating fixture (30) and a computer-controlled ultrasound transducer (29). The skull fixation apparatus (13) is utilized in combination with ultrasound, CT or MRI scan transparencies and with a digitizing tablet (27) in order to transfer transparency data both as to skull fixation benchmarks and tumor locations into a computer (28). The transducer (29) is cooperatively arranged with the translating system (30) such that the benchmarks of the skull fixation apparatus (13) are utilized to derive X, Y and Z linear coordinates and two rotary coordinates which are at right angles to one another which are also input into the computer (28) such that the computer (28) is then capable of automatically driving the transducer (29) and positioning it at the appropriate location for producing (29) volume lesions in the brain at the site of the identified brain tumors or other selected tissues.

Ultrasound brain lesioning system

A method of treatment of tissue with focussed ultrasound comprises placing adjacent the tissue to be treated a reflector of ultrasound or an ultrasound energy conversion device which converts received ultrasound energy to heat, stores the heat and then releases the heat over time into the tissue to be treated. An ultrasound transducer is then oriented with its focal point adjacent the reflector or ultrasound energy conversion device. The tissue is then irradiated with high intensity focussed ultrasound while the reflector or ultrasound energy conversion device is in place.

Focussed ultrasound tissue treatment method

An ultrasound transducer for use with an ultrasound brain lesioning system includes an acoustic focusing lens, a piezoelectric transducer plate disposed in spaced relation with the focusing lens, an acoustic coupling medium disposed between the focusing lens and the transducer, and a pressurized fluid contacting the rear surface of the transducer to maintain a spaced relation between the transducer plate and the back surface of the lens. An electrical excitation signal is supplied to the transducer to promote production of an ultrasonic signal by the transducer.

Francis J. Fry

Papers

Dependence of ultrasonic attenuation and absorption in dog soft tissues on temperature and thermal dose

Localization and therapy system for treatment of spatially oriented focal disease

Ultrasound brain lesioning system

Focussed ultrasound tissue treatment method

Ultrasonic treatment transducer with pressurized acoustic coupling