Abstract: An imaging system is provided comprising an imaging probe and at least one delivery device. The imaging probe comprises an elongate shaft, a rotatable optical core and an optical assembly. The elongate shaft comprises a proximal end, a distal portion, and a lumen extending between the proximal end and the distal portion. The rotatable optical core is positioned within the lumen of the elongate shaft and comprises a proximal end and a distal end. The rotatable optical core is configured to optically and mechanically connect with an interface unit. The optical assembly is positioned in the elongate shaft distal portion and proximate the rotatable optical core distal end. The optical assembly is configured to direct light to tissue and collect reflected light from the tissue. The imaging probe is constructed and arranged to collect image data from a patient site. The delivery device is constructed to engage the imaging probe.

Abstract: A rotary pump for a fluid metering system is provided. The rotary pump reciprocates, and is reversed by a signal from a limit switch that is deflected by an actuator arm on a rotating sleeve of the pump system.

Abstract: A method and apparatus of automatically locating in an image of a blood vessel the lumen boundary at a position in the vessel and from that measuring the diameter of the vessel. From the diameter of the vessel and estimate blood flow rate, a number of clinically significant physiological parameters are then determine and various user displays of interest generated. One use of these images and parameters is to aid the clinician in the placement of a stent. The system, in one embodiment, uses these measurements to allow the clinician to simulate the placement of a stent and to determine the effect of the placement. In addition, from these patient parameters various patient treatments are then performed.

Abstract: The invention provides a frictional torque limiter assembly for an imaging core spinning in a patient's body. The torque limiter assembly torsionally isolates the imaging core from a motor that spins the imaging core. An interference fit between a slitted drive tube and a spacer tube acts as a clutch that allows a spinning imaging probe to slow or stop relative to the motor until the motor is stopped, thereby preventing an unsafe condition.

Abstract: An imaging system for a patient comprises an imaging probe. The imaging probe comprises: an elongate shaft for insertion into the patient and comprising a proximal end, a distal portion, and a lumen extending between the proximal end and the distal portion; a rotatable optical core comprising a proximal end and a distal end, the rotatable optical core configured to optically and mechanically connect with an interface unit; a probe connector positioned on the elongate shaft proximal end and surrounding at least a portion of the rotatable optical core and an optical assembly positioned in the elongate shaft distal portion and proximate the rotatable optical core distal end, the optical assembly configured to direct light to tissue and collect reflected light from the tissue. A shear-thinning fluid can be provided between the elongate shaft and the rotatable optical core, such as to reduce undesired rotational variations of the rotatable optical core.

Abstract: A method and apparatus of automatically locating in an image of a blood vessel the lumen boundary at a position in the vessel and from that measuring the diameter of the vessel. From the diameter of the vessel and estimated blood flow rate, a number of clinically significant physiological parameters are then determined and various user displays of interest generated. One use of these images and parameters is to aid the clinician in the placement of a stent. The system, in one embodiment, uses these measurements to allow the clinician to simulate the placement of a stent and to determine the effect of the placement. In addition, from these patient parameters various patient treatments are then performed.

Abstract: The invention provides a frictional torque limiter assembly for an imaging core spinning in a patient's body. The torque limiter assembly torsionally isolates the imaging core from a motor that spins the imaging core. An interference fit between a slitted drive tube and a spacer tube acts as a clutch that allows a spinning imaging probe to slow or stop relative to the motor until the motor is stopped, thereby preventing an unsafe condition.

Abstract: In part, the invention relates to a method for sizing a stent for placement in a vessel. In one embodiment, the method includes the steps of: dividing the vessel into a plurality of segments, each segment being defined as the space between branches of the vessel; selecting a starting point that appears to have substantially no disease; defining the diameter at this point to be the maximum diameter; calculating the maximal diameter of the next adjacent segment according to a power law; measuring the actual diameter of the next adjacent segment; selecting either the calculated maximum diameter or the measured maximum diameter depending upon which diameter is larger; using the selected maximum diameter to find the maximum diameter of this next segment; iteratively proceeding until the entire length of the vessel is examined; and selecting a stent in response to the diameters of the end proximal and distal segments.

Abstract: A method and apparatus of automatically locating in an image of a blood vessel the lumen boundary at a position in the vessel and from that measuring the diameter of the vessel. From the diameter of the vessel and estimated blood flow rate, a number of clinically significant physiological parameters are then determined and various user displays of interest generated. One use of these images and parameters is to aid the clinician in the placement of a stent. The system, in one embodiment, uses these measurements to allow the clinician to simulate the placement of a stent and to determine the effect of the placement. In addition, from these patient parameters various patient treatments are then performed.

Abstract: An apparatus comprising a torque wire connected to an imaging probe; and a torque limiter defining a bore, a first end of the torque limiter being in mechanical communication with a motor, a second end of the torque limiter being in mechanical communication with the torque wire, the torque wire being disposed through the bore of the torque limiter. The torque limiter comprises a member defining at least one cutout which causes the torque limiter to break when rotational force on the torque wire exceeds a predetermined amount, thereby decoupling the motor from the torque wire.

Abstract: An apparatus comprising a torque wire connected to an imaging probe; and a torque limiter defining a bore, a first end of the torque limiter being in mechanical communication with a motor, a second end of the torque limiter being in mechanical communication with the torque wire, the torque wire being disposed through the bore of the torque limiter. The torque limiter comprises a member defining at least one cutout which causes the torque limiter to break when rotational force on the torque wire exceeds a predetermined amount, thereby decoupling the motor from the torque wire.

Abstract: In part, the invention relates to a catheter suitable for flushing a vessel. The catheter can include separated lumens and components that improve image data collection. In one embodiment, the catheter includes a catheter wall; a distal portion defining a distal lumen (62), the distal lumen having a first end terminating at the distal end of the catheter and a second end (30) terminating at an exit port in the catheter wall; a proximal portion defining proximal lumen (42), the proximal lumen having a first end terminating at the proximal end of the catheter and a second end terminating at a vent port (34) in the catheter wall; and a valve (50,54) positioned adjacent the vent port, the valve permitting fluid to exit the proximal lumen, but preventing particulate matter from the environment from entering the proximal lumen. In one embodiment, the valve comprises a piston (50) and spring (54) located in the proximal lumen (42).

Abstract: A method and apparatus of automatically locating in an image of a blood vessel the lumen boundary at a position in the vessel and from that measuring the diameter of the vessel. From the diameter of the vessel and estimate blood flow rate, a number of clinically significant physiological parameters are then determine and various user displays of interest generated. One use of these images and parameters is to aid the clinician in the placement of a stent. The system, in one embodiment, uses these measurements to allow the clinician to simulate the placement of a stent and to determine the effect of the placement. In addition, from these patient parameters various patient treatments are then performed.

Abstract: An optical coherence tomography system and method with integrated pressure measurement. In one embodiment the system includes an interferometer including: a wavelength swept laser; a source arm in communication with the wavelength swept laser; a reference arm in communication with a reference reflector; a first photodetector having a signal output; a detector arm in communication with the first photodetector, a probe interface; a sample arm in communication with a first optical connector of the probe interface; an acquisition and display system comprising: an A/D converter having a signal input in communication with the first photodetector signal output and a signal output; a processor system in communication with the A/D converter signal output; and a display in communication with the processor system; and a probe comprising a pressure sensor and configured for connection to the first optical connector of the probe interface, wherein the pressure transducer comprises an optical pressure transducer.

Abstract: In part, the invention relates to catheters, methods, and blood clearing technologies suitable for use in an optical coherence tomography system. The optical coherence tomography system includes a control system, a probe including a catheter defining a lumen and a rotatable optical fiber located within the lumen, a fluid cartridge holder in communication with the lumen of the probe, a pump to move fluid from the fluid cartridge to the lumen of the probe; and a motor configured to rotate and pull the optical fiber through the lumen of a blood vessel. The pump and the motor are controlled by the control system. The catheter can include a wall that bounds the lumen of the probe, which defines a flush port and includes a valve in fluid communication with the flush port, the valve configured to permit fluid from the lumen to pass through the wall.

Abstract: In part, the invention relates to methods, apparatus, and systems suitable for determining a fractional flow reserve (FFR) and variations of modifications thereof One embodiment relates to a method and apparatus for obtaining a corrected FFR in a vessel having a stenosis. In one aspect, the invention relates to an apparatus for measuring corrected FFR of a vessel having a stenosis. In one embodiment, the apparatus includes a probe comprising an optical coherence tomography assembly and a pressure assembly; and a processor in communication with the optical coherence tomography assembly and the pressure assembly. In one embodiment, the pressure assembly measures values of pressure in predetermined locations the vessel and communicates them to the processor. In one embodiment, a dual guidewire is used to reduce the interference in the pressure measurement.

Abstract: An OCT system and method with integrated pressure measurement. In one embodiment, the system includes an interferometer; a wavelength swept laser; a source arm in communication with the wavelength swept laser; a reference arm in communication with a reference reflector; a first photoreceiver having a signal output; a detector arm in communication with the first photoreceiver, a probe interface; a sample arm in communication with a first optical connector of the probe interface; an acquisition and display system comprising: an A/D converter having a signal input in communication with the first photoreceiver signal output and a signal output; a processor system in communication with the A/D converter signal output; and a display in communication with the processor system; and a probe comprising a pressure sensor and configured for connection to the first optical connector of the probe interface, wherein the pressure transducer comprises an optical pressure transducer.

Abstract: An optical coherence tomography system and method with integrated pressure measurement. In one embodiment the system includes an interferometer including: a wavelength swept laser; a source arm in communication with the wavelength swept laser; a reference arm in communication with a reference reflector; a first photodetector having a signal output; a detector arm in communication with the first photodetector, a probe interface; a sample arm in communication with a first optical connector of the probe interface; an acquisition and display system comprising: an A/D converter having a signal input in communication with the first photodetector signal output and a signal output; a processor system in communication with the A/D converter signal output; and a display in communication with the processor system; and a probe comprising a pressure sensor and configured for connection to the first optical connector of the probe interface, wherein the pressure transducer comprises an optical pressure transducer.

Abstract: A method and apparatus of automatically locating in an image of a blood vessel the lumen boundary at a position in the vessel and from that measuring the diameter of the vessel. From the diameter of the vessel and estimated blood flow rate, a number of clinically significant physiological parameters are then determined and various user displays of interest generated. One use of these images and parameters is to aid the clinician in the placement of a stent. The system, in one embodiment, uses these measurements to allow the clinician to simulate the placement of a stent and to determine the effect of the placement. In addition, from these patient parameters various patient treatments are then performed.

Abstract: In part, the invention relates to an optical probe including a torque wire; an optical fiber positioned within the torque wire; a beam director positioned coaxial with and adjacent to one end of the optical fiber; and an overcladding, positioned adjacent to and over the optical fiber and the beam director, the overcladding defining an air gap adjacent the beam director so as to cause total internal reflection alight passing from the optical fiber through the beam director. In one embodiment, the optical probe includes a beam expander and a beam shaper coaxial with and located between the optical fiber and the beam director. In another embodiment, the optical probe further includes a marker band positioned over a portion of the overcladding. In yet another embodiment, the overcladding is made of flurosilica glass.