Abstract: The present invention relates to a pressure sensor module for use in catheters having a pressure sensor operable to provide a signal representative of pressure. The pressure sensor includes a sensing side and a pressure reference side. At least one signal transmission media is coupled to the sensor for transmitting the signal representative of pressure. A convex-shaped carrier is provided having a slot formed to expose the sensing side of the sensor. The convex-shaped carrier is adapted for receiving the sensor such that the sensing side of the sensor is adjacent the slot. A bonding material is provided for mounting the sensor to the carrier. The pressure sensing module provides ease of installation and manufacture because the module may easily be bonded to and installed within a catheter.

Abstract: The present invention relates to a pressure sensor module for use in catheters having a pressure sensor operable to provide a signal representative of pressure. The pressure sensor includes a sensing side and a pressure reference side. At least one signal transmission media is coupled to the sensor for transmitting the signal representative of pressure. A convex-shaped carrier is provided having a slot formed to expose the sensing side of the sensor. The convex-shaped carrier is adapted for receiving the sensor such that the sensing side of the sensor is adjacent the slot. A bonding material is provided for mounting the sensor to the carrier. The pressure sensing module provides ease of installation and manufacture because the module may easily be bonded and installed within a catheter.

Abstract: A device, system, and method for determining the sensing performance of pressure-sensing devices. The device generates dynamic pressure waveforms that enable researchers and medical personnel to accurately assess the characteristics and performance of a particular pressure-sensing device. The system and methods allow for comparison of performance between two or more pressure-sensing devices, including catheter tip pressure transducers and fluid-filled catheters. The system may also be used to practice priming and preparing catheters for insertion into a living body, as the system provides immediate feedback that may indicate the presence of air in the system.

Abstract: The present invention relates to a pressure sensor module for use in catheters having a pressure sensor operable to provide a signal representative of pressure. The pressure sensor includes a sensing side and a pressure reference side. At least one signal transmission media is coupled to the sensor for transmitting the signal representative of pressure. A convex-shaped carrier is provided having a slot formed to expose the sensing side of the sensor. The convex-shaped carrier is adapted for receiving the sensor such that the sensing side of the sensor is adjacent the slot. A bonding material is provided for mounting the sensor to the carrier. The pressure sensing module provides ease of installation and manufacture because the module may easily be bonded and installed within a catheter.

Abstract: The present invention relates to a catheter pressure transducer having a pressure sensing module operable to provide a signal representative of pressure. The pressure sensor includes a sensing side and a pressure reference side. At least one signal transmission media is coupled to the sensor for transmitting the signal representative of pressure. A convex-shaped carrier is provided having a slot formed to expose the sensing side of the sensor. The convex-shaped carrier is adapted for receiving the sensor such that the sensing side of the sensor is adjacent the slot. A bonding material is provided for mounting the sensor to the carrier. The pressure sensing module provides ease of installation and manufacture because the module may easily be bonded and installed within a catheter.

Abstract: An inverted sensor module for sensing physical and chemical fluid characteristics in a vessel in a living body. The inverted sensor module includes an inverted sensor bonded to a hollow carrier so that sensing occurs in the lumen of the inverted sensor module. An inverted sensor module comprising one or more inverted sensors is implantable and allows fluid to flow through, thereby allowing for measurements of acute and chronic conditions. The inverted sensor module may be used in series with other inverted sensor modules to assess trends such as pressure gradients along a bloodstream.

Abstract: An external fluid-filled catheter pressure transducer for monitoring fluid pressure characteristics in a vessel in a living body. The external fluid-filled catheter pressure transducer includes an inverted sensor bonded to a hollow carrier so that measuring occurs on the inside of the carrier. The fluid-filled catheter pressure transducer allows pressure measurements to be taken in vessels smaller than 1 mm in diameter. A method for manufacturing an external fluid-filled catheter pressure transducer describes connecting sections of tubing (semi-rigid and flexible) to an inverted sensor module, and providing a reference port for the inverted sensor module.

Abstract: The invention provides a method and system for reconstructing a high-fidelity pressure waveform with a balloon catheter used in a heart. First, a balloon catheter having an air line is inserted into the aorta of the heart. The air line is then closed and sufficient air is introduced in order to equalize the pressure in the balloon catheter and the aorta. The AC components of the aortic pressure and the mean aortic pressure are detected separately and then added to form a high-fidelity pressure waveform. The high fidelity pressure waveform may be displayed on an oscilloscope, a patient monitor, or other suitable display.

Abstract: The present invention relates to a pressure sensor module for use in catheters having a pressure sensor operable to provide a signal representative of pressure. The pressure sensor includes a sensing side and a pressure reference side. At least one signal transmission media is coupled to the sensor for transmitting the signal representative of pressure. A convex-shaped carrier is provided having a slot formed to expose the sensing side of the sensor. The convex-shaped carrier is adapted for receiving the sensor such that the sensing side of the sensor is adjacent the slot. A bonding material is provided for mounting the sensor to the carrier. The pressure sensing module provides ease of installation and manufacture because the module may easily be bonded and installed within a catheter.

Abstract: A device that contemplates a unique and advantageous reduced size catheter tip measurement device. By using a bottom support member and a thin outer insulating layer, rather than a tubular metal casing, to support and isolate the electrical measurement sensor, the present invention drastically reduces feature size possible with current structures for catheter tip measurement devices. More specifically, the device contemplates a reduced size catheter tip pressure transducer device. The device includes a catheter body that has a support member attached to its distal tip. The support member has a support surface for a semiconductor pressures sensor that provides mechanical stability to the pressure sensor. The exposed electrical and metal areas of the device are insulated from surrounding tissues and fluids by an outer insulating layer, which is preferably a polyimide sleeve.

Abstract: A pulse transducer is disclosed having a pressure sensor for detecting pulse pressure and a velocity sensor for simultaneously detecting pulse velocity in blood vessels. The present invention allows reproduction of pulse pressure and velocity waveforms. The present invention combines a conventional applanation tonometer with a mounted velocity sensor, such as a Doppler crystal. The velocity sensor is placed proximate to the pressure sensor to allow simultaneous detection of pulse velocity, in real time, at substantially the same location as the pulse pressure measurement. The sensing direction of the velocity sensor may be at an angle with respect to the sensing direction of the pressure sensor. The present invention may be applied vertically to a vessel for proper applanation, while ultrasound, traveling across the vessel, may be used to detect a major component of the velocity.

Abstract: The invention relates to catheters having a distally-mounted balloon and pressure sensor and to methods of placing such catheters within physiological vessels. Catheters have a central lumen extending through the catheter and a pressure sensor which lies within the distal portion of the central lumen but does not occlude the lumen. Additionally, catheters may have a Doppler velocity measurement sensor affixed to the distal end of the catheter for measuring fluid velocity distal to the catheter. Inflation of the balloon prevents vessel wall contact with other portions of the catheter tip during flow-directed placement of the catheter. During catheter placement to obtain a wedge pressure, the balloon is inflated until fluid velocity detected with the Doppler sensor is substantially zero.

Abstract: A method and assembly is provided which allows measurement of intracranial fluid charateristics at the intracranial region of the brain. The invention contemplates a method of implanting a ventricular catheter having one end residing in the ventricular region and the other end exiting the cranial region at a distal location. A grooved needle allows placement of a transducer tipped catheter and rerouting of both the ventricular, in-dwelling catheter and the transducer tipped catheter placed within the in-dwelling catheter. Intracranial fluid characteristics are monitored by an electrically coupled distal monitor. Further, access to the intracranial fluid is also provided to allow either short-term or long-term withdrawal or injection of intracranial fluid.

Abstract: A method and assembly is provided which allows measurement of intracranial fluid characteristics at the intracranial region of the brain. The invention contemplates a method of implanting a ventricular catheter having one end residing in the ventricular region and the other end exiting the cranial region at a distal location. A grooved needle allows placement of a transducer tipped catheter and rerouting of both the ventricular, in-dwelling catheter and the transducer tipped catheter placed within the in-dwelling catheter. Intracranial fluid characteristics are monitored by an electrically coupled distal monitor. Further, access to the intracranial fluid is also provided to allow either short-term or long-term withdrawal or injection of intracranial fluid.

Abstract: A method and system for introducing one or more devices into a biological fluid vessel. The system includes a device having a coupling structure comprising a pair of spaced-apart fingers adapted for receiving a guidewire therebetween. Preferably, the system includes a guidewire having a constricted fitting region at its proximal end where the coupling structure may be easily connected to the guidewire. In one use, the method is used in coronary angioplasty to diagnose and treat stenosis across a coronary valve or other vessel in the coronary arterial tree. In this method, a guiding catheter is percutaneously inserted with its distal end proximate the ostium. A guidewire is inserted through the guiding catheter and subselectively positioned in a region of interest in the coronary arterial tree. Multiple devices may be coupled to the guidewire in accordance with the present invention and then threaded down the guidewire and positioned in the region of interest.

Abstract: A method and assembly for inserting one or more diagnostic sensors into a biological fluid vessel for diagnosing the condition of the vessel or fluid. Different types of diagnostic sensors, such as pressure, velocity, pH, temperature, or infusion catheter, are particularly adapted for use with a steerable guidewire for selective positioning in the vessel. In one application, the method is used in coronary diagnosis, to determine the pressure gradient or other fluid characteristics across a coronary valve or stenosis in the coronary arterial tree. In this method, a guiding catheter is percutaneously inserted with its distal end proximate the ostium. A guidewire is inserted through the guiding catheter and subselective positioned in a region of interest in the coronary arterial tree. Multiple diagnostic sensors are then threaded down the guidewire and positioned in the region of interest.

Abstract: An apparatus and method for sensing in vivo the fluid pressure differential between spaced locations in a biological fluid vessel using a single pressure transducer. The transducer has a deformable member mounted to a housing; a conduit extends within the housing with one end opening at a location spaced from the transducer and the other end opening adjoining the inner surface of the member. With the housing inserted in the biological fluid vessel, the outer surface of the deformable member is exposed to the fluid pressure adjacent the member, while the inner surface is exposed to the fluid pressure within the conduit. The deformable member flexes in response to the fluid pressure differential across the member, which is a direct measure of the fluid pressure differential between spaced-apart locations in the fluid-filled vessel.

Abstract: A method and assembly for inserting a plurality of sensors into a biological fluid vessel for diagnosing the condition of the vessel or fluid. A pressure sensor is described which is particularly adapted for use with a steerable guidewire for selective positioning in the vessel. In one application, the method is used in coronary diagnosis, to determine the pressure gradient across a coronary valve or stenosis in the coronary arterial tree. In this method, a guiding catheter is percutaneously inserted with its distal end proximate the ostium. A guidewire is inserted through the guiding catheter and subselectively positioned in a region of interest in the coronary arterial tree. Multiple pressure sensors are then threaded down the guidewire and positioned in the region of interest. Advantageously, such pressure sensors are approximately 3 French in diameter, allowing multiple sensors to be threaded through the guiding catheter and positioned in the small arteries of the coronary arterial tree.

Abstract: A method and assembly for inserting a plurality of sensors into a biological fluid vessel for diagnosing the condition of the vessel or fluid. A pressure sensor is described which is particularly adapted for use with a steerable guidewire for selective positioning in the vessel. In one use, the method is used in coronary diagnosis, to determine the pressure gradient across a coronary valve or stenosis in the coronary arterial tree. In this method, a guiding catheter is percutaneously inserted with its distal end proximate the ostium. A guidewire is inserted through the guiding catheter and subselectively positioned in a region of interest in the coronary arterial tree. Multiple pressure sensors are then threaded down the guidewire and positioned in the region of interest. Advantageously, such pressure sensors are approximately 3 French in diameter, allowing multiple sensors to be threaded through the guiding catheter and positioned in the small arteries of the coronary arterial tree.

Abstract: A catheter fluid-velocity flow probe is disclosed which has greater sensitivity and which dissipates less heat during operation than flow probes heretofore constructed. These significant results are achieved by providing two electromagnets in the probe to generate two separate magnetic fields. Each electrode is positioned between the poles of an electromagnet in the region of highest magnetic flux density of each electromagnet. The electromagnets are reduced in size, and a tubing may be inserted in the central portion of the probe during construction. This tubing permits the attachment of additional measuring devices to the distal end of the probe to permit multiple measurements in a fluid to be made simultaneously.