Abstract: In an in situ interrogation system for multiple wavelength interferometers a fringe spectrum that includes non-quadrature-spaced radiation-intensity samples is analyzed to obtain a high resolution relative phase measurement of the optical path length difference associated with the fringe spectrum. The fringe spectrum can be analyzed to obtain a fringe number and a quadrant as well, which can be combined with the relative phase measurement to obtain a high precision measurement of the absolute optical path length difference. An environmental condition corresponding to the absolute optical path length difference can be measured using the measurement of the absolute optical path length difference including salinity, pressure, density, and refractive index of a medium.

Abstract: Guided ablation instruments are disclosed for creating lesions in tissue, especially cardiac tissue for treatment of arrhythmias, including atrial fibrillation. In one aspect of the invention, a percutaneous catheter is disclosed with an endoscope positionable in the instrument's distal end region to obtain an image. The image allows the clinician to determine whether contact has been achieved (or blood has been cleared from an ablative energy transmission path) before ablation begins or while ablation is occurring. In one embodiment, percutaneous ablation catheters are disclosed having at least one central lumen and one or more balloon structures at the distal end region of the instrument. Also disposed in the distal end region are an illuminating light source and an endoscope capable of collecting sufficient light to relay an image to the user. The instruments can further include an ablation element.

Abstract: Guided ablation instruments are disclosed for creating lesions in tissue, especially cardiac tissue for treatment of arrhythmias, including atrial fibrillation. In one aspect of the invention, a percutaneous catheter is disclosed with an endoscope positionable in the instrument's distal end region to obtain an image. The image allows the clinician to determine whether contact has been achieved (or blood has been cleared from an ablative energy transmission path) before ablation begins or while ablation is occurring. In one embodiment, percutaneous ablation catheters are disclosed having at least one central lumen and one or more balloon structures at the distal end region of the instrument. Also disposed in the distal end region are an illuminating light source and an endoscope capable of collecting sufficient light to relay an image to the user. The instruments can further include an ablation element.

Abstract: In an in situ interrogation system for multiple wavelength interferometers a fringe spectrum that includes non-quadrature-spaced radiation-intensity samples is analyzed to obtain a high resolution relative phase measurement of the optical path length difference associated with the fringe spectrum. The fringe spectrum can be analyzed to obtain a fringe number and a quadrant as well, which can be combined with the relative phase measurement to obtain a high precision measurement of the absolute optical path length difference. An environmental condition corresponding to the absolute optical path length difference can be measured using the measurement of the absolute optical path length difference including salinity, pressure, density, and refractive index of a medium.

Abstract: In an interrogation system for multiple wavelength interferometers a fringe spectrum that includes non-quadrature-spaced radiation-intensity samples is analyzed to obtain a high resolution relative phase measurement of the optical path-length difference associated with the fringe spectrum. The fringe spectrum can be analyzed to obtain a fringe number and a quadrant as well, which can be combined with the relative phase measurement to obtain a high precision measurement of the absolute optical path-length difference. An environmental condition corresponding to the absolute optical path-length difference can be measured using the measurement of the absolute optical path-length difference.

Abstract: Systems for visualizing cardiac tissue during an ablation procedure are provided. In general, the systems include an imaging module configured to measure absorbance data at first and second wavelengths wherein the ratio of these absorbance values identifies the nature of the tissue (e.g., lesion, de novo tissue, etc.). The imaging module can also include a video system having at least two chips with corresponding bandpass filters centered at the first and second target wavelengths. The system can also include a processor and/or video monitor for combining the images produced by the various chips, determining treated and non-treated tissue based on the ratio of absorbance values at the target wavelengths, and displaying images of the treatment area. Methods of visualizing cardiac treatment areas during ablation procedures are also provided herein.

Abstract: A multi-modal communication system and method capable of operating underwater, at an interface such as the surface of water, and in the atmosphere using a plurality of communication modes including optical, acoustic, and radio frequency communication. The nodes include underwater vehicles, divers, buoys, aerial vehicles, and shore-based operators. In one aspect, the system and method are capable of high-speed optical and long-range acoustic communication through transitioning between communication modes dependent upon signal conditions. It is another aspect to provide a system and method designed for clandestine operation that is not easily detected when in use.

Abstract: A system and method to reduce fouling of a surface subjected to an aquatic environment with a light source. According to one aspect, an antifouling system including an LED for emitting UV radiation, one or more mounts for directing emitted UV radiation toward the surface, and control circuitry for driving the LED disposed in a watertight housing. According to another aspect, an antifouling system which employs a fluorescent lamp disposed within a pressure vessel including a UV-transmissive material to allow UV light to pass through the pressure vessel and reduce bio-fouling of any surface.

Abstract: An underwater system including at least one input device that is in sensory communication with water and generates input signals. The system further includes at least one optical transmitter and at least one optical receiver that allow omni-directional transmission and reception through water of optical signals representing the input signals, and allow data rates greater than 1 Mbps.

Abstract: A system and method to broadcast an optical signal through an amorphous medium, including a primary emitter capable of producing a primary optical signal during at least one broadcast period and capable of transmitting the primary optical signal through the amorphous medium. A secondary emitter, separate from the primary emitter and in operation during at least a portion of the broadcast period, produces a secondary emission detectable by a detector during the broadcast period. A signal entrainment controller, in communication with the primary emitter and the secondary emitter, synchronizes the secondary emitter with the primary emitter to generate a resultant signal of higher intensity than the primary signal by itself.

Abstract: An underwater system including at least one input device that is in sensory communication with water and generates input signals. The system further includes at least one optical transmitter and at least one optical receiver that allow omni-directional transmission and reception through water of optical signals representing the input signals, and allow data rates greater than 1 Mbps.

Abstract: Systems for visualizing cardiac tissue during an ablation procedure are provided. In general, the systems include an imaging module configured to measure absorbance data at first and second wavelengths wherein the ratio of these absorbance values identifies the nature of the tissue (e.g., lesion, de novo tissue, etc.). The imaging module can also include a video system having at least two chips with corresponding bandpass filters centered at the first and second target wavelengths. The system can also include a processor and/or video monitor for combining the images produced by the various chips, determining treated and non-treated tissue based on the ratio of absorbance values at the target wavelengths, and displaying images of the treatment area. Methods of visualizing cardiac treatment areas during ablation procedures are also provided herein.

Abstract: A system and method to broadcast an optical signal through an amorphous medium, including a primary emitter capable of producing a primary optical signal during at least one broadcast period and capable of transmitting the primary optical signal through the amorphous medium. A secondary emitter, separate from the primary emitter and in operation during at least a portion of the broadcast period, produces a secondary emission detectable by a detector during the broadcast period. A signal entrainment controller, in communication with the primary emitter and the secondary emitter, synchronizes the secondary emitter with the primary emitter to generate a resultant signal of higher intensity than the primary signal by itself.

Abstract: The systems and methods described herein provide a reconfigurable, long-range, optical modem-based underwater communication network. In particular, the network provides a low power, low cost, and easy to deploy underwater optical communication system capable of being operated at long distances. Optical modem-based communication offer high data rate, omni-directional spatial communication in the visual spectrum. The omni-directional aspect of communication is advantageous because precise alignment of communication units may not be required. The optical modems may be deployed via unmanned underwater vehicles (UUVs) and physically connected by tethers.

Abstract: Systems for visualizing cardiac tissue during an ablation procedure are provided. In general, the systems include an imaging module configured to measure absorbance data at first and second wavelengths wherein the ratio of these absorbance values identifies the nature of the tissue (e.g., lesion, de novo tissue, etc.). The imaging module can also include a video system having at least two chips with corresponding bandpass filters centered at the first and second target wavelengths. The system can also include a processor and/or video monitor for combining the images produced by the various chips, determining treated and non-treated tissue based on the ratio of absorbance values at the target wavelengths, and displaying images of the treatment area. Methods of visualizing cardiac treatment areas during ablation procedures are also provided herein.

Abstract: In an interrogation system for multiple wavelength interferometers a fringe spectrum that includes non-quadrature-spaced radiation-intensity samples is analyzed to obtain a high resolution relative phase measurement of the optical path-length difference associated with the fringe spectrum. The fringe spectrum can be analyzed to obtain a fringe number and a quadrant as well, which can be combined with the relative phase measurement to obtain a high precision measurement of the absolute optical path-length difference. An environmental condition corresponding to the absolute optical path-length difference can be measured using the measurement of the absolute optical path-length difference.

Abstract: Guided ablation instruments are disclosed for creating lesions in tissue, especially cardiac tissue for treatment of arrhythmias, including atrial fibrillation. In one aspect of the invention, a percutaneous catheter is disclosed with an endoscope positionable in the instrument's distal end region to obtain an image. The image allows the clinician to determine whether contact has been achieved (or blood has been cleared from an ablative energy transmission path) before ablation begins or while ablation is occurring. In one embodiment, percutaneous ablation catheters are disclosed having at least one central lumen and one or more balloon structures at the distal end region of the instrument. Also disposed in the distal end region are an illuminating light source and an endoscope capable of collecting sufficient light to relay an image to the user. The instruments can further include an ablation element.

Abstract: Guided ablation instruments are disclosed for creating lesions in tissue, especially cardiac tissue for treatment of arrhythmias, including atrial fibrillation. In one aspect of the invention, a percutaneous catheter is disclosed with an endoscope positionable in the instrument's distal end region to obtain an image. The image allows the clinician to determine whether contact has been achieved (or blood has been cleared from an ablative energy transmission path) before ablation begins or while ablation is occurring. In one embodiment, percutaneous ablation catheters are disclosed having at least one central lumen and one or more balloon structures at the distal end region of the instrument. Also disposed in the distal end region are an illuminating light source and an endoscope capable of collecting sufficient light to relay an image to the user. The instruments can further include an ablation element.

Abstract: A cardiac ablation instrument capable of removing blood from a treatment area is provided. The instrument includes a catheter configured to deliver a distal end thereof to a patient's heart. The instrument can also include an expandable element coupled to the distal end of the catheter wherein the expandable member is configured to be positioned adjacent a target area thereby defining a treatment area between the expandable member and the target area. Further, the instrument can include an irrigation mechanism configured to dispense an irrigation fluid from the catheter thereby displacing blood from the treatment area. Additionally, the instrument includes an energy emitter configured to deliver energy to tissue within the treatment area. The instrument can also include a contact sensor configured to determine the presence of such blood within the treatment area. Methods for ablating tissue are also provided.

Abstract: A cardiac ablation instrument capable of removing blood from a treatment area is provided. The instrument includes a catheter configured to deliver a distal end thereof to a patient's heart. The instrument can also include an expandable element coupled to the distal end of the catheter wherein the expandable member is configured to be positioned adjacent a target area thereby defining a treatment area between the expandable member and the target area. Further, the instrument can include an irrigation mechanism configured to dispense an irrigation fluid from the catheter thereby displacing blood from the treatment area. Additionally, the instrument includes an energy emitter configured to deliver energy to tissue within the treatment area. The instrument can also include a contact sensor configured to determine the presence of such blood within the treatment area. Methods for ablating tissue are also provided.