9483 results about "Electric potential" patented technology

An electrode sealing assembly for use with an electrosurgical instrument for sealing tissue includes first and second jaw members which are movable from a first position in spaced relation relative to one another to at least one second position for grasping tissue. The jaw members include electrically conductive sealing plates designed to selectively transmit electrosurgical energy to tissue disposed between the sealing plates. The jaw members also include a thermoelectric cooling plate having a first surface in direct contact with an outer surface of the sealing plate. The thermoelectric cooling plate includes first and second electrical connections on opposite sides of the jaw member. The first connection is configured to selectively transmit a first electrical potential and the second connection is configured to selectively transmit a second electrical potential such that heat generated by the sealing plates is transferred away from the tissue via the thermoelectric cooling plate.

Sensors (10, 110, 210, 310, 410) and a method for detecting an analyte are described. Sensors (10, 110, 210, 310, 410) each have a volume of a hydrophilic medium (24) that retains an amount of analyte proportionate to the concentration of analyte in a biological fluid, electrodes (12) and a redox enzyme in contact with medium (24), and an electron transfer mediator. The fluid contacts sensors (10, 110, 210, 310, 410) and at initially predetermined intervals intermittently applies a potential to electrode (12) sufficient to oxidize the mediator and sensing current through electrode (12) as a function of the duration of the applied potential. The applied mediator oxidizing applied potential is maintained for a period of time sufficient to determine the rate of change of current with time through electrode (12). The current flow is correlated with the current flow for known concentrations of the analyte in medium (24).

A system and method for using magnetic resonance imaging to increase the accuracy of electrophysiologic procedures is disclosed. The system in its preferred embodiment provides an invasive combined electrophysiology and imaging antenna catheter which includes an RF antenna for receiving magnetic resonance signals and diagnostic electrodes for receiving electrical potentials. The combined electrophysiology and imaging antenna catheter is used in combination with a magnetic resonance imaging scanner to guide and provide visualization during electrophysiologic diagnostic or therapeutic procedures. The invention is particularly applicable to catheter ablation, e.g., ablation of atrial fibrillation. In embodiments which are useful for catheter ablation, the combined electrophysiology and imaging antenna catheter may further include an ablation tip, and such embodiment may be used as an intracardiac device to both deliver energy to selected areas of tissue and visualize the resulting ablation lesions, thereby greatly simplifying production of continuous linear lesions. The invention further includes embodiments useful for guiding electrophysiologic diagnostic and therapeutic procedures other than ablation. Imaging of ablation lesions may be further enhanced by use of MR contrast agents. The antenna utilized in the combined electrophysiology and imaging catheter for receiving MR signals is preferably of the coaxial or “loopless” type. High-resolution images from the antenna may be combined with low-resolution images from surface coils of the MR scanner to produce a composite image. The invention further provides a system for eliminating the pickup of RF energy in which intracardiac wires are detuned by filtering so that they become very inefficient antennas. An RF filtering system is provided for suppressing the MR imaging signal while not attenuating the RF ablative current. Steering means may be provided for steering the invasive catheter under MR guidance. Other ablative methods can be used such as laser, ultrasound, and low temperatures.

A liquid crystal device including a front electrode layer, rear electrode layer, a liquid crystal material located between the front electrode layer and the rear electrode layer. A polarizer is located between the liquid crystal material and the front electrode layer and changing an electrical potential between the rear electrode layer and the front electrode layer modifies portions of the liquid crystal material to change the polarization of the light incident thereon. A plurality of light sensitive elements are located together with the rear electrode layer and a processor determines the position of at least one of the plurality of light sensitive elements that has been inhibited from sensing ambient light.

An ECG lead set including an ECG electrode assembly and a lead set hub. ECG electrode includes at least one electrode configured to receive biopotential signals from a patient, a plug connector for connecting said ECG electrode assembly, a web, connected between the at least one electrode and the plug connector and configured to form an electrical connection therebetween. The lead set hub includes at least one receptacle configured to receive the plug connector of the ECG electrode assembly.

A chemical vapor deposition process is carried out in a reactor chamber with an ion shower grid that divides the chamber into an upper ion generation region and a lower process region, the ion shower grid having plural orifices oriented in a non-parallel direction relative to a surface plane of the ion shower grid. A workpiece is placed in the process region facing the ion shower grid, the workpiece having a workpiece surface generally facing the surface plane of the ion shower grid. A gas mixture is furnished comprising deposition precursor species into the ion generation region and the process region is evacuated at an evacuation rate sufficient to create a pressure drop across the ion shower grid from the ion generation region to the process region whereby the pressure in the ion generation region is at least several times the pressure in the process region. A layer of material of a desired thickness is deposited on the workpiece by: (a) applying plasma source power to generate a plasma of the deposition precursor species in the ion generation region, and (b) applying a grid potential to the ion shower grid to create a flux of ions from the plasma through the grid and into the process region.