Abstract: Relief of urethral obstruction is achieved by heat ablation of prostatic tissue by an ablation electrode passed within the urethra to a position in the prostate near the point of urethral obstruction. The electrode is coupled to a high frequency power supply to ablatively heat the urethra and the prostatic tissue near the urethra. Image guidance of the electrode placement is monitored by an imaging device. The temperature of the tissue is sensed at the electrode to control the high frequency heating energy and ablation process. The electrode has a blunt tip to help prevent piercing of the wall of the urethra during insertion of the electrode into the urethra through the penis and the positioning of the electrode tip near to the point of urethral obstruction. Several forms of electrodes, apparatus, and methods accommodate the specific objectives.

Abstract: A system for quantitative computer graphic determination of positions on a patient's anatomy and positions on associated equipment located near the patient's anatomy in relation to anatomical data, as from CT or MR scanning. A first camera produces a quantitative electronic readout of its field-of-view which provides a determination of relative spacial coordinates of uniquely identifiable points in its field-of-view. A second camera produces a quantitative electronic readout of its field-of-view which provides a determination of relative spacial coordinates of uniquely identifiable points in its field-of-view. The two cameras are located with respect to the patient's anatomy and the associated equipment so that the fields-of-view of the cameras include both the patient's anatomy and the equipment, but are taken from different directions. A body marker is positioned with respect to the patient's anatomy at a known position relative to said patient anatomy.

Abstract: This invention involves apparatus and methods for relating image scan data of a patient's anatomy from an imaging scanner to a device attached to said patient's anatomy or to an apparatus located nearby said patient's anatomy. In one embodiment it includes identification of fiducial points or markers on or near the patient's anatomy in the image scan data, and subsequently relating these fiducial points to reference points or structures connected to an apparatus attached to or nearby the patient's body. Such an apparatus might be a surgical head clamp or stereotactic frame or arc which has been attached to the patient's head at the time of surgery. A mapping is made between the coordinate frame data of the scan image to the coordinate reference frame of the patient attachment means or external apparatus by physically referencing the fiducial points to the patient attachment means or external apparatus.

Abstract: A method and apparatus for altering a function of neural tissue in a patient. An electromagnetic signal is applied to the neural tissue through an electrode. The electromagnetic signal has a frequency component above the physiological stimulation frequency range and an intensity sufficient to product an alteration of the neural tissue, the alteration causing the patient to experience a reduction in pain, and a waveform that prevents lethal temperature elecation of the neural tissue during application of the electromagnetic signal to the neural tissue.

Abstract: Relief of urethral obstruction is achieved by heat ablation of prostatic tissue by an ablation instrument passed within the urethra to a position in the prostate near the point of urethral obstruction. An electrode is coupled to a high-frequency power supply to ablatively heat the urethra and the prostatic tissue near the urethra. Guidance of the electrode placement may be monitored by an imaging device. The instrument may consist of a catheter with an inflatable balloon structure for positioning the instrument. The temperature of the tissue may be sensed at the electrode to control the high-frequency heating energy and ablation process.

Abstract: A skin-based band is fixed to a patient's skin in a repeatable position and includes reference markers which, attached to the skin band, can be visualized in tomographic image scanning. The reference markers appear as reference marker images in the image scan data from the image scan and correspond to coordinate positions in the image scan coordinate system. The reference markers also provide corresponding reference marker positions in the physical space of the patient's anatomy, which may correspond to a stereotactic coordinate system associated with a digitized navigator or frameless stereotactic reference system near the patient. The band can also be placed on the patient again at the time of surgical intervention, and the reference markers can be touched or referenced by the surgical navigator in the stereotactic coordinate system.

Abstract: A method and apparatus are provided for altering a function of tissue in a patient. An electromagnetic signal generated by a signal generator is applied to the tissue to be altered through an electrode. The electromagnetic signal has at least one frequency component above the physiologic stimulation frequency range at an intensity sufficient to produce an alteration of the tissue and a waveform that inhibits temperature elevation to the lethal temperature range of the tissue. Both externally coupled and fully implanted electrode and signal generator systems can be used at tissue sites in various parts of the body.

Abstract: This invention relates to the destruction of pathological volumes or target structures such as cancerous tumors or aberrant functional target tissue volumes by direct thermal destruction. In the case of a tumor, the destruction is implemented in one embodiment of the invention by percutaneous insertion of one or more radiofrequency probes into the tumor and raising the temperature of the tumor volume by connection of these probes to a radiofrequency generator outside of the body so that the isotherm of tissue destruction enshrouds the tumor. The ablation isotherm may be predetermined and graded by proper choice of electrode geometry and radiofrequency (rf) power applied to the electrode with or without temperature monitoring of the ablation process. Preplanning of the rf electrode insertion can be done by imaging of the tumor by various imaging modalities and selecting the appropriate electrode tip size and temperature to satisfactorily destroy the tumor volume.

Abstract: This patent relates to an apparatus involving optical cameras, one or more, and computer graphic means for registering anatomical subjects seen in the cameras to computer graphic image displays of image data taken from CT, MRI or other scanning image means. One or more cameras may be set up to view the anatomical subject. The anatomical subject has been scanned previously by an imaging machine such as a CT scanner and the data has been stored in a computer with computergraphic readout. The computer has software which enables rotation translation and scaling of the anatomical subject seen in the image data. By registering the field of view of the camera or cameras with the corresponding graphic view of the image data, a registration of the optical view with the scanner image view can be made. In this way, points identifiable in the camera view can be located in the image data view and vice versa.

Abstract: A method and apparatus for altering a function of neural tissue in a patient. An electromagnetic signal is applied to the neural tissue through an electrode. The electromagnetic signal has a frequency component above the physiological stimulation frequency range and an intensity sufficient to produce an alteration of the neural tissue, the alteration causing the patient to experience a reduction in pain, and a waveform that prevents lethal temperature elevation of the neural tissue during application of the electromagnetic signal to the neural tissue.

Abstract: For repeat localization and immobilization of the head, neck and/or torso of a patient's body, immobilizing structures are used to secure the head and the neck and torso in a relative orientation in the position and relative orientation. A reference structure determines the relative position of the head and neck or torso so that the same configuration of these portions of the body can be achieved on a scanner couch or treatment machine couch repeatedly. Several forms of head and neck or torso immobilizers accommodate specific objectives and several forms of reference structures accomplish repositioning and patient position orientation.

Abstract: A skin-based band is fixed to a patient's skin in a repeatable position and includes reference markers which, attached to the skin band, can be visualized in tomographic image scanning. The reference markers appear as reference marker images in the image scan data from the image scan and correspond to coordinate positions in the image scan coordinate system. The reference markers also provide corresponding reference marker positions in the physical space of the patient's anatomy, which may correspond to a stereotactic coordinate system associated with a digitized navigator or frameless stereotactic reference system near the patient. The band can also be placed on the patient again at the time of surgical intervention, and the reference markers can be touched or referenced by the surgical navigator in the stereotactic coordinate system.

Abstract: This invention relates to the quantitative determination of a target or volume in the living body relative to external apparatus based on CT (computer tomography) or other image data. The invention describes a means of taking CT image data of the anatomy and of natural or implanted index positions on the patient's body, and relating the CT data to a coordinate system related to external apparatus which may be in fixed position relative to the patient. One implementation uses a transformation between the CT image data coordinate system and the second coordinate system. This makes it possible to do frame-based or frameless stereotactic target identification and approaches without the need for attaching a frame to the patient at the time of CT scanning.

Abstract: A system for computer graphic determination and display of a patient's anatomy, as from CT or MR scanning, and stored along with associated equipment in an object field including the patient's anatomy. A first digitizing camera structure produces a signal representative of its field-of-view which defines coordinates of index points in its field-of-view. A second digitizing camera structure produces similar output for an offset field-of-view. The two camera positions are defined with respect to the patient's anatomy so that the fields-of-view of the cameras include both the patient's anatomy and the equipment, but are taken from different directions. Index markers are for fixing points in the fields of view and accordingly locate equipment relative to said patient anatomy. The index markers are provided by variety of structures including, light sources in various forms as reflectors, diodes, and laser scanner structures to provide a visible grid, mesh or cloud of points.

Abstract: A method and apparatus for altering a function of neural tissue in a patient. An electromagnetic signal is applied to the neural tissue through an electrode. The electromagnetic signal has a frequency component above the physiological stimulation frequency range and an intensity sufficient to produce an alteration of the neural tissue, the alteration causing the patient to experience a reduction in pain, and a waveform that prevents lethal temperature elevation of the neural tissue during application of the electromagnetic signal to the neural tissue.

Abstract: This invention relates to apparatus for calibrating and recalibrating a digitized navigator or so-called frameless stereotactic instrument or device during a surgical operation. The apparatus enables calibration for the stereotactic digitizer to be recovered after sterile draping of the patient, movement of the patient's head during operation, relative movement of the patient's head and reference apparatus associated with the stereotactic digitizer, power failures, or other events which could compromise calibration of the stereotactic digitizer during the operation which would otherwise preclude continuations using the digitizer. It also provides convenient means for initial calibration or repeat calibration, should that be necessary. The apparatus is, in one embodiment, cooperatively coupled to, or coupled so as to move with, the portion of the patient's body which is being operated upon and enables the repositioning of the recalibration means after sterile draping.

Abstract: A head and neck positioner and immobilizer having an over-arm structure that can be reproducibly attached to a couch, either CT or MR imaging couch or a treatment couch as for a LINAC radiosurgery system. The positioner enables adjustable immobilization of the patient's head. The over-arm accepts a graphic reference with fiducials such as points, rods, or diagonals that can reference a selected target position determined from tomographic imaging, such as CT or MRI slices or imaging data, to the over-arm or to the couch onto which the arm is attached. Alternately, a target localizer or positioning device can be attached to the over-arm or to the couch to which the arm is attached for positioning the coordinates of the selected target position as determined using the image scan data with the graphic reference fiducials observed in it.

Abstract: The intraoperative calibration of an arbitrary surgical instrument relative to a surgical navigation digitizing system is achieved by a calibration guide. The calibration guide is established in position and orientation relative to the digitizing system coordinate system. The surgical instrument is aligned to the calibration guide during calibration to establish its probe and end orientation in the digitizer coordinates. The instrument carries a marker structure which is trackable in the digitizer coordinates to enable tracking by rigid-body transformation of the instruments probe and end position after calibration in the calibration guide.

Abstract: A system for quantitative computer graphic determination of positions on a patient's anatomy and positions on associated equipment located near the patient's anatomy in relation to anatomical data, as from CT or MR scanning. A first camera produces a quantitative electronic readout of its field-of-view which provides a determination of relative spacial coordinates of uniquely identifiable points in its field-of-view. A second camera produces a quantitative electronic readout of its field-of-view which provides a determination of relative spacial coordinates of uniquely identifiable points in its field-of-view. The two cameras are located with respect to the patient's anatomy and the associated equipment so that the fields-of-view of the cameras include both the patient's anatomy and the equipment, but are taken from different directions. A body marker is positioned with respect to the patient's anatomy at a known position relative to said patient anatomy.

Abstract: This patent relates to instrumentation for confirming the position of a target, frequently in the head, at the isocenter of a linear accelerator or other beam delivery system. Typically, the anatomical target is determined by CT, NMR, angiographic, X-ray, or other imaging means. The position of the target and the coordinates of the target are referenced to a head fixation means. That head fixation means is subsequently attached to the beam delivery system, such as a linear accelerator (LINAC). To simulate the position of the target prior to putting the patient there, this rectilinear phantom pointer can be used. It has three coordinate slide scales on it that are orthogonal and are calibrated with distant scales. Moving these three scales positions a radiopaque marker to stand at the phantom point of the actual anatomical target. This enables direct confirmation of patient positioning and centering of the beam isocenter at the desired target.