Surgery – Diagnostic testing – Cardiovascular
Reexamination Certificate
1999-07-16
2001-12-18
O'Connor, Cary (Department: 3736)
Surgery
Diagnostic testing
Cardiovascular
C073S054410, C600S373000, C600S377000, C600S438000
Reexamination Certificate
active
06331163
ABSTRACT:
FIELD OF THE INVENTION
The present invention relates generally to a method and device for fixation of a sensor in a bodily lumen and for protection of the sensor during insertion into a bodily lumen.
BACKGROUND OF THE INVENTION
Sensors for the monitoring and/or recordation of various human physical, chemical and/or physiological parameters are known in the art. U.S. Pat. No. 4,485,813 describes a sensor that may be permanently implanted in a specific location within the human body in an implantable medical device such as a pacemaker. This sensor is used to monitor certain physical and/or physiological parameters of the subject in which it has been implanted. This sensor can be maintained in the subject for extended periods of time to continuously monitor information about the subject.
A severe limitation to the sensor described in U.S. Pat. No. 4,485,813 is the limited number of possible locations in which it can be implanted due to the requirement that the sensor be located in a medical device such as a pacemaker and the difficulty of fixation independently. This limitation on the location and fixation of the sensor limits the usefulness of the sensor for inter-lumen applications.
Sensors used to monitor parameters within lumens include sensors made of very thin membranes that are highly sensitive to mechanical pressure. As a result there is a great risk of the sensor being damaged during insertion, deployment and/or positioning. Damage to the sensor could result in poor performance or non-operability of the sensor. For example, should the membrane of a sensor break during insertion, the sensor would be rendered inoperable. Due to the risks associated with the procedures for the insertion of sensors, there would be great costs and risks involved should a sensor be damaged or destroyed during insertion. Thus, there is also a need for a device and method of protecting sensors during insertion and fixation.
For such sensors, including those machined from silicon, another concern is the erosion that the pressure-sensitive membrane undergoes when it is implanted in a patient and exposed for a prolonged period of time to bodily fluids and other naturally occurring agents inside the patient. Contrary to the prevalent view, it was discovered that a sensor machined from silicon does not exhibit a satisfactory degree of bio-compatibility with the naturally occurring bodily fluids and agents it encounters when implanted inside a patient. After a certain amount of time, these fluids and agents slowly begin dissolving the sensor, degrading the accuracy of the data produced by the sensor, and indeed, after a period of a few months, dissolving the thin membrane and other parts of the sensor completely. What is therefore needed is a bio-compatible protective coating for the sensor that resists the corrosive effect of the human body's naturally occurring fluids. By minimizing the erosion of the sensor membrane, such a protective coating would not only extend the useful life of the sensor, the coating would also maintain the accuracy of the data produced by the sensor while it is implanted inside the patient.
SUMMARY OF THE PRESENT INVENTION
It is, therefore, an object of the present invention to provide a method and device for fixation of a sensor in a bodily lumen. Through the use of such a method and device, remotely interrogated sensors may be fixed within bodily lumens. Such sensors may be used to record and/or monitor parameters such as, for example, physiological parameters, e.g., pressure and velocity of flow, and biochemical parameters, e.g., level of gases and biochemical substances in the fluid contained in the lumen.
The monitoring of conditions in lumens today dictates some level of intervention and/or intrusion and the frequency of such monitoring is limited by the relative risk of the required intervention. The present invention, therefore, provides a sensor device which may be implanted, either temporarily or permanently, in a lumen and interrogated from an exterior position, for example, the surface of the body, at any time without any physical intrusion.
The present invention provides a method and device for the fixation of such sensors in specific desired locations and/or preferred positions in the lumen. Such fixation of the sensors may be achieved at the time of any required surgical intervention or independently by catheterization. Furthermore, the sensor may be connected to the repair device, e.g., the stitches of a bypass, an aneurismal repair device, a stent, etc., or mounted on its own dedicated fixation device.
A sensor may be fixed inside a lumen by any number of means, including directly attaching the sensor in place, for example, by including holes in the sensor, e.g., around its periphery, and attaching the sensor to the stitches of a bypass during surgery, or through the use of a surgical adhesive. A sensor may also be positioned inside a lumen using a carrier or support (of any shape and size) which may be part of, or coupled to a repair device, e.g., a stent or aneurismal correction device which holds the sensor in place adjacent to or near the repair device. Additionally, a sensor may be positioned inside a lumen using a dedicated device, e.g., an anchoring ring, which is held within a lumen and fixed in place, for example, by expansion with a catheter balloon. A dedicated device may be used, for example, when fixation is necessary but no corrective device is employed at the desired location. The anchoring ring does not necessarily have to be circular in shape, but may instead be oval or any other shape best suited for the location where placed. Additionally, the anchoring ring may have a separate carrier or support to hold the sensor. The carrier or support may be any shape or size, including, for example, circular, square, rectangular, diamond shaped, linear with or without a bent or curved end, etc, and it may be constructed as only a border or as a solid piece of material. As discussed below, the anchoring ring may be expandable by a balloon catheter, or some other method, such as self expansion.
Multiple sensors may be attached to a carrier or carriers, for example, two sensors with one placed on each side of a stent, or two sensors attached at both connections of a bypass section, e.g., one sensor at the entrance to an aneurismal sleeve and one at the outside of the sleeve to monitor for a possible leak around the sleeve. Additionally, a sensor may have multiple repair devices or dedicated devices supporting it within a lumen, either with or without a carrier, for example, a sensor supported between two anchoring rings.
A sensor may be supported by or connected to a carrier, for example, by providing a groove-like depression(s) or notch-like depression(s) in the sensor into which a portion(s) of the carrier may be inserted, or the sensor may be configured such that a portion(s) of the sensor, for example, a lip-like extension(s) or protrusion(s), may extend beyond the dimensions of the carrier to be supported thereby. Additionally, the sensor may be attached to the carrier, for example, by welding and/or glueing or any combinations of the above.
After a sensor is fixed within a lumen, for example, during an intervention procedure such as aneurismal device implantation, PTCA, coronary bypass surgery, etc., it may thereafter be monitored periodically to track any of a variety of parameters or to assess the effectiveness of the procedure that was performed. For example, the sensor may be monitored periodically to assess the long term progress or deterioration of the corrective effect, and the progress of relevant symptoms of a disease.
Multiple sensors may be implanted and may be monitored individually or simultaneously to derive gradients along a lumen and across a repair device or section. Such sensors may be fixed in any number of positions within a lumen, for example, on both sides of a lesion treated by PTCA with or without a stent, on both sides of a bypass section, and before, after and around an aneurismal repair device, etc.
The fixation dev
Carter Ryan
Kenyon & Kenyon
Microsense Cardiovascular Systems (1196) Ltd.
O'Connor Cary
LandOfFree
Protective coating for bodily sensor does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Protective coating for bodily sensor, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Protective coating for bodily sensor will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2564356