Abstract: A laser system for a spectroscopic catheter system uses multiple semiconductor gain media having gain peaks at different wavelengths. The output from the gain media is preferably coupled into single-mode fiber using conventional opto-electronic packaging techniques. As a result, the laser oscillator source has a spectral output that is wider than the gain bandwidth of a single medium to enable it to access the entire spectrum of interest, which is presently in the near infrared. Moreover, the semiconductor gain media can be packaged in a stable and controlled environment for long-term performance.

Abstract: An apparatus and associated method for detecting vulnerable plaque within a lumen defined by an intraluminal wall is described. The apparatus includes a probe having a distal portion and a proximal portion. The apparatus includes an optical waveguide extending along the probe. The optical waveguide is configured to carry optical radiation between the distal and proximal portions, and has a distal end in communication with the intraluminal wall. The apparatus includes an interferometer coupled to the optical waveguide and configured to provide an interference signal for sub-surface imaging of the intraluminal wall, and a processing module configured to provide spectroscopic information from detected intensity of light collected from the intraluminal wall.

Abstract: The invention relates to methods and devices for characterizing tissue in vivo, e.g., in walls of blood vessels, to determine whether the tissue is healthy or diseased.

Abstract: A spectroscope includes first and second beam redirectors in optical communication with first and second fibers respectively. The first and second beam redirectors are oriented to illuminate respective first and second areas. The second area is separated from the first area by a separation distance that exceeds the separation distance between the first and second beam redirectors.

Abstract: An apparatus and associated method for detecting vulnerable plaque within a lumen defined by an intraluminal wall is described. The apparatus includes a probe having a distal portion and a proximal portion. The apparatus includes an optical waveguide extending along the probe. The optical waveguide is configured to carry optical radiation between the distal and proximal portions, and has a distal end in communication with the intraluminal wall. The apparatus includes an interferometer coupled to the optical waveguide and configured to provide an interference signal for sub-surface imaging of the intraluminal wall, and a processing module configured to provide spectroscopic information from detected intensity of light collected from the intraluminal wall.

Abstract: A spectroscope includes first and second beam redirectors in optical communication with first and second fibers respectively. The first and second beam redirectors are oriented to illuminate respective first and second areas. The second area is separated from the first area by a separation distance that exceeds the separation distance between the first and second beam redirectors.

Abstract: The invention relates to methods and devices for characterizing tissue in vivo, e.g., in walls of blood vessels, to determine whether the tissue is healthy or diseased, and include methods of displaying results with or without thresholds.

Abstract: A method for detecting a complete or partial obstruction in a vessel through an intervening fluid includes receiving spectroscopic responses at different locations of a vessel wall, e.g., a vein or artery, through an intervening fluid, preferably blood. Spectroscopic responses are generated by irradiating the vessel wall at different locations and detecting spectra at those locations. In preferred embodiments, the radiation used is in the near infrared (NIR) region of the electromagnetic spectrum. The thrombus is located by determining whether fluctuations, spatial and/or spectral, of the spectral responses are indicative of thrombus.

Abstract: The invention relates to methods and devices for characterizing tissue in vivo, e.g., in walls of blood vessels, to determine whether the tissue is healthy or diseased, and include methods of displaying results with or without thresholds.

Abstract: An optical catheter system comprising an intraluminal catheter that provides optical signals to a patient and carries optical signals from the patient, an outer housing, and an inner carriage that moves longitudinally relative to the outer housing and rotates relative to the outer housing during operation when the catheter system is being driven by a pullback and rotation system. The optical catheter system has an interlock system that prevents rotation and longitudinal movement of the inner carriage in the outer housing until attached to the pullback and rotation system. The pullback and rotation system comprises a frame and a catheter system interface, attached to the frame, to which the catheter system is coupled. A carriage drive system is further provided that moves longitudinally and rotates relative to the frame to provide rotation and longitudinal drive to the catheter system.

Abstract: An optical catheter system comprising an intraluminal catheter that provides optical signals to a patient and carries optical signals from the patient, an outer housing, and an inner carriage that moves longitudinally relative to the outer housing and rotates relative to the outer housing during operation when the catheter system is being driven by a pullback and rotation system. The optical catheter system has an interlock system that prevents rotation and longitudinal movement of the inner carriage in the outer housing until attached to the pullback and rotation system. The pullback and rotation system comprises a frame and a catheter system interface, attached to the frame, to which the catheter system is coupled. A carriage drive system is further provided that moves longitudinally and rotates relative to the frame to provide rotation and longitudinal drive to the catheter system.

Abstract: An optical catheter system comprising an intraluminal catheter that provides optical signals to a patient and carries optical signals from the patient, an outer housing, and an inner carriage that moves longitudinally relative to the outer housing and rotates relative to the outer housing during operation when the catheter system is being driven by a pullback and rotation system. The optical catheter system has an interlock system that prevents rotation and longitudinal movement of the inner carriage in the outer housing until attached to the pullback and rotation system. The pullback and rotation system comprises a frame and a catheter system interface, attached to the frame, to which the catheter system is coupled. A carriage drive system is further provided that moves longitudinally and rotates relative to the frame to provide rotation and longitudinal drive to the catheter system.

Abstract: An optical catheter system comprising an intraluminal catheter that provides optical signals to a patient and carries optical signals from the patient, an outer housing, and an inner carriage that moves longitudinally relative to the outer housing and rotates relative to the outer housing during operation when the catheter system is being driven by a pullback and rotation system. The optical catheter system has an interlock system that prevents rotation and longitudinal movement of the inner carriage in the outer housing until attached to the pullback and rotation system. The pullback and rotation system comprises a frame and a catheter system interface, attached to the frame, to which the catheter system is coupled. A carriage drive system is further provided that moves longitudinally and rotates relative to the frame to provide rotation and longitudinal drive to the catheter system.

Abstract: A system for identifying vulnerable plaque includes an illumination subsystem for passing an illumination beam, modulated by a first modulation waveform, through a catheter. A receiving subsystem detects a collection beam, which is modulated by a second modulated waveform, from the catheter. A processing subsystem in communication with the receiving subsystem determines a relative phase difference between the first and second modulation waveforms.

Abstract: The invention features an apparatus and an associated method for illuminating a target area. The apparatus includes reflectors defining a first optical cavity. The first optical cavity defines a first set of longitudinal modes. The apparatus includes a first gain medium defining a first gain band. The first gain medium is configured to cause a plurality of the longitudinal modes of the first set to oscillate over an oscillation band within the first gain band when the first gain medium is pumped at an operative level. The apparatus includes a first optical waveguide positioned within the first optical cavity. The first optical waveguide has a length selected to cause a temporal coherence length of light emitted from the first optical cavity to be shorter than a scattering distance associated with the target area.

Abstract: A system for displaying diagnostic data includes a display on which is displayed an image having an anatomic map and a diagnostic map. The diagnostic map, which is disposed at a location indicative of the spatial distribution of the diagnostic data, shows a spatial distribution of that data.

Abstract: A spectroscope includes an optical fiber extending through a catheter, and in communication with an optical system. The optical system has a finite focal length.

Abstract: A system for assessing the quality of the optical connection between a catheter and a console is described that avoids the necessity of a calibration port, although one can still be provided if desired. It operates by monitoring the level of light returning from the catheter head and specifically the degree to which this returning light is attenuated. Reflections will arise at the catheter head's optical window due to the discontinuity between the refractive index of the window and that of air or other medium into which the head is inserted. Since the refractive index of the optical window is known and with the head in a known medium such as air, the level of reflection is known. This enables a controller in the console to calculate the round trip loss and thus monitor the loss in the catheter-console interface. Moreover, since round-trip loss is measured, the accuracy is improved by a factor of two over calibration port systems that only measure loss in a single pass arrangement.

Abstract: A laser system for a spectroscopic catheter system utilizes an overmoded cavity in order to reduce mode hoping induced power fluctuations during wavelength scanning. In the preferred embodiment, a semiconductor gain medium is used to reduce cost. A fiber pigtail is used to define the laser cavity, which has a tight cavity mode spacing of less that 15 Gigahertz. A diffraction grating is used as the tuning element. A cylindrical lens is used to reduce alignment tolerances and thereby increase manufacturability.

Abstract: A laser system for a spectroscopic catheter system utilizes an overmoded cavity in order to reduce mode hoping induced power fluctuations during wavelength scanning. In the preferred embodiment, a semiconductor gain medium is used to reduce cost. A fiber pigtail is used to define the laser cavity, which has a tight cavity mode spacing of less that 15 Gigahertz. A diffraction grating is used as the tuning element. A cylindrical lens is used to reduce alignment tolerances and thereby increase manufacturability.