| Optical window for an intracorporeal device -> Monitor Keywords |
|
|
  Optical window for an intracorporeal deviceUSPTO Application #: 20060106287Title: Optical window for an intracorporeal device Abstract: Optical windows for intracorporeal devices, intracorporeal devices comprising a window and a method for forming a window for an intracorporeal device are provided. The method comprises placing within a mold an assembly comprising a mandrel located within a pair of parts separated by a collar of window material, heating the window preform effective to cause the window material to soften, and applying force to urge together the pair of parts to deform the window material so as to form a window. The intracorporeal devices, such as imaging devices, include guidewires, catheters, endoscopes. In addition, the method is suitable for joining plastic parts to other parts, such as metal and ceramic parts. (end of abstract) Agent: Fulwider Patton - Los Angeles, CA, US Inventors: William E. Webler, Michael D. Whitt, Marc M. Jalisi, Andrej M. Chudy, Kevin M. Phillips, Marc L. Speck USPTO Applicaton #: 20060106287 - Class: 600176000 (USPTO) Related Patent Categories: Surgery, Endoscope, Having Imaging And Illumination Means, Having Particular Distal Lens Or Window The Patent Description & Claims data below is from USPTO Patent Application 20060106287. Brief Patent Description - Full Patent Description - Patent Application Claims
CROSS-REFERENCE TO RELATED APPLICATIONS [0001] This is a divisional application of co-pending parent application having U.S. Ser. No. 10/025,334, filed Dec. 18, 2001, the contents of which are hereby incorporated by reference. FIELD OF THE INVENTION [0002] The present invention relates generally to methods and apparatus for manufacturing an optical window for an intracorporeal device that provides functional access to a body lumen, and to methods for joining parts together. In particular, the invention is directed to methods and apparatus for making an optical window for an imaging guidewire, catheter, or endoscope. BACKGROUND OF THE INVENTION [0003] Intracorporeal devices are devices suitable for introduction into a patient's body, for example, into a body lumen of a patient. Many clinical procedures require the insertion of wires, tubes, probes or other objects into a body lumen of a patient. For example, guidewires and catheters may be used for gaining access to the coronary vasculature, as in an angiogram or in angioplasty. A guidewire is a thin, flexible device used to provide a guiding rail to a desired location within the vasculature (or other body cavity) of a patient. A balloon catheter is a device with an interior lumen with at least a portion of the catheter being able to expand. In coronary angioplasty, a balloon catheter, guided by a guidewire, is positioned within a partially-occluded coronary artery where its balloon portion is expanded in order to press against and enlarge the lumen of a blood vessel in which it is situated. Alternatively, endoscopy requires the introduction of an endoscope into the lumen of a patient, as may be done during a colonoscopy. [0004] The ability to decide where to locate a catheter during a clinical procedure can be improved by providing interior images of the body lumen, such as the blood vessels during angioplasty or the colon during colonoscopy. It is often critical to the success of an angioplasty procedure that a balloon catheter be properly located within a blood vessel. Thus, imaging by guidewire, catheter, or other such device can be of great importance to the success of the procedure. [0005] Imaging endoscopes, guidewires and catheters have been described, as in U.S. Pat. Nos. 5,321,501 and 5,459,570 to Swanson et al., and U.S. Pat. No. 6,134,003 to Tearney et al. Catheters adapted for optical imaging using non-visible light may be useful as well, as disclosed in U.S. Pat. No. 5,935,075 to Casscells et al. Such imaging devices typically use an optical fiber to carry light. All patents, supra and infra, are hereby incorporated by reference in their entirety. [0006] It is often advantageous to have a window in an imaging catheter, imaging guidewire, endoscope, or other imaging probe to allow optical access between the exterior of the device and the optical fiber or light path within the device. U.S. Pat. No. 6,134,003 to Tearney et al. discloses a rigid plastic clear window, or using three or more metal or plastic metering rods to connect two parts of a guidewire across a window. However, the choice of material and the method of construction of the window is critical to the success of the device. A window made of brittle material may break and shatter if it fails, leading to the dispersion of broken window shards within a body lumen if such failure occurs during a clinical procedure. Such materials are thus unacceptable in devices designed for use within a body lumen. A non-brittle, plastic material does not have the disadvantages of a brittle window material. [0007] However, a suitable connection between the window material and other components of an intracorporeal imaging device is required. For use in an intracorporeal imaging device such as a guidewire, catheter, or endoscope, the window must be attached to proximal and distal portions of the intracorporeal imaging device. [0008] Conventional techniques for forming and attaching windows have been found to be difficult and unsuccessful. Use of rods to connect two parts of a guidewire or other intracorporeal imaging device across a window blocks visual access and interferes with the imaging function of a window. The extremely small dimensions of the window components makes conventional molding, extrusion molding, injection molding and insert molding processes difficult and costly to use in making a window for these intracorporeal devices, and such methods only provide a low likelihood of success. [0009] For example, the small outer diameter of a guidewire makes it extremely difficult to use conventional methods to successfully press fit an extruded window over the formed guidewire mating ends. Conventional attempts to expand or drill out the inner diameter of the window tubing to obtain a fit present problems with alignment, obtaining tooling and maintaining low enough tolerances to make a good bond of either desired type. Further, if one were to use conventional techniques and to expand the extruded window to allow a fit over the ends of the guidewire, some window material would assume a larger than desired outer diameter, which would have to be cleanly removed by some other operation. Additionally, the tolerances associated with extrusion (typically +/-0.001'') would require that the average cross-sectional area of the window wall be significantly lower than the maximum cross-section possible within its dimensional constraints, so that, with prior art methods, the strength and utility of the window could be impaired. [0010] Conventional methods for bonding the ends of the window with an adhesive so as to mate appropriately with the proximal and distal portions of a guidewire or catheter suffer from similar disadvantages as other conventional methods. Conventional molding processes force a melted plastic into a mold cavity where it rapidly cools. In order to form a tubular window a mold pin must be placed inside the mold to leave a hollow interior. However, with such conventional techniques, while forcing melted plastic into a mold, at least a portion of the melted plastic would cool significantly while flowing into the mold. Conventional techniques would then require that the plastic be forced very rapidly into the cavity under high pressures to fill the cavity before cooling in an attempt to avoid this problem. However, such rapid, high pressure flow would damage or warp the mold pin forming the inner diameter of the window. This is due to the length of the window inner diameter that is required to ensure that the fiber optic assembly can be reliably aligned such that the light exits the window in all bend, temperature and assembly conditions. [0011] Attempting to balance the molding forces by having more than one plastic entrance into the mold requires a more complex and expensive mold. This method suffers from disadvantages due to the low volume of plastic in the window, and the uncertainty involved in timing the plastic flow's entry into the cavity. Additionally, molds and equipment of this type are very expensive. [0012] Accordingly, there is need in the art for methods for forming a window for an imaging guidewire, catheter or endoscope. SUMMARY OF THE INVENTION [0013] The present invention is directed to methods for forming windows and for joining materials. In some embodiments, the invention is directed to methods for forming a window for an intracorporeal device, windows formed by the novel methods, and intracorporeal devices comprising a window formed by the methods, The novel methods may be used to form optical windows for guidewires, catheters, endoscopes, and other intracorporeal devices useful for accessing a body lumen. For example, the optical window formed by the methods of the invention may comprise a smooth translucent or transparent tube comprising a portion of an imaging guidewire. The methods can be used to form or mold into place very small plastic parts, especially those that require tight tolerances and a small inner diameter of a relatively long length Thus, in some embodiments, the methods of the invention are effective to join plastic parts, in particular very small plastic parts, with other parts, such as metal or ceramic parts, to form joints and junctions. Devices and methods utilizing the methods of the present invention are disclosed in co-owned application Ser. No. 10/024,986, "Optical Guidewire Having Windows or Apertures" to Jalisi et al.; application Ser. No. 10/025,515, "Rotatable Ferrules and Interfaces for Use with an Optical Guidewire," to Webler et al.; and application Ser. No. 10/025,149, "Sheath for Guiding Imaging Instruments," to Webler et al., all of which are filed concurrently herewith, and the disclosures of which are all hereby incorporated by reference in their entirety. [0014] An optical window formed by the methods of the invention may include a smooth translucent or transparent tube that is attached to distal and proximal portions of an imaging guidewire, an imaging catheter, an imaging endoscope, or other device suitable for accessing a body lumen. By way of example, the methods will be illustrated with a description of the formation of a window for an imaging guidewire. However, it will be understood that the methods may also be used to form windows for catheters, endoscopes, and any other intracorporeal device useful for accessing a body lumen. [0015] The invention includes methods for forming a window for an intracorporeal device, comprising placing an assembly with a window preform at least partially within a mold, softening the window preform, and applying force. In some embodiments, softening the window preform may be accomplished by heating the window preform. The assembly includes a proximal tubular member, a distal member, a window preform, and a mandrel. A window preform is disposed between the proximal tubular member and the distal member. A window preform may flow when desired, and may be made, at least in part, of a material that softens when its temperature is raised. The softened window preform material may be deformed onto proximal and distal portions of an intracorporeal device, which portions may be configured so as to contact, engage or grip the window perform or formed window. The assembly has a longitudinal axis, and the mandrel is disposed along the longitudinal axis at least partially within the proximal tubular member, the window preform, and the distal member. The step of raising the temperature of the window preform may be effective to soften the window preform. The step of applying force is effective to urge together the proximal tubular member and the distal member, and is effective to deform the window preform so as to form a window or to join separate parts together. In other embodiments, the window preform is made, at least in part, of a material that hardens upon warming, exposure to light, or other treatment. [0016] Heating the window preform may be effected, for example, by at least one method selected from the group consisting of induction heating, conduction heating, infra-red radiation, ultrasonic heating, friction heating, hot air heating, and allowing the preform temperature to rise to ambient temperature. [0017] In some embodiments of the methods for forming a window for an intracorporeal device, the mandrel protrudes from an end of the assembly, or, in further embodiments of the methods, the mandrel protrudes from each end of the assembly. The mandrel may have a polished distal end, may be coated with a coating such as a lubricious coating, lined with a lining such as a lubricious lining, and may be polished and/or treated, for example, to have a smooth or a lubricious surface. Any lubricious coating, such as a coating of a fluoropolymer (e.g., Teflon), titanium nitride, or other coating known in the art, may be used in the practice of the novel methods. [0018] The invention also provides methods for joining a plastic part with a tubular member. Such methods include placing at least partially within a mold an assembly comprising a tubular member, a mandrel and a plastic preform that softens when heated; softening the plastic preform; and applying force effective to urge together the tubular member and the plastic preform effective to deform the plastic preform and to join the plastic preform to the tubular member. In some embodiments, the plastic preform may be softened by heating. [0019] The mold may be comprised of a suitable material or combination of materials having a higher melt temperature than the window material, such as metal, plastic, ceramic, glass, and combinations of these materials. In some embodiments of the methods, the mold comprises borosilicate glass. The mold may be coated on one or more surfaces with a coating such as a lubricious coating, lined on one or more surfaces with a lining such as a lubricious lining, and may be polished and/or treated on one or more surfaces, for example, to have a smooth or a lubricious surface. Any lubricious coating may be used in the practice of the novel methods. [0020] Optical radiation may be useful in imaging and optical sensing. Window materials comprise translucent materials (i.e., materials capable of transmitting optical radiation such as light), including materials which may be transparent (i.e., translucent materials capable of transmitting an image). The terms "light" and "optical radiation" are used herein to mean electromagnetic radiation including but not limited to visible light, infrared radiation, ultraviolet radiation, and other radiation. Optical radiation may include radiation having a wavelength in the range of between about 0.1 to about 3 micron, and may particularly include radiation having a wavelength between about 0 75 micron to about 2.5 micron, or radiation having a wavelength between about 0.1 micron to about 1 micron. Continue reading... Full patent description for Optical window for an intracorporeal device Brief Patent Description - Full Patent Description - Patent Application Claims Click on the above for other options relating to this Optical window for an intracorporeal device patent application. ###  How KEYWORD MONITOR works... a FREE service from FreshPatents1. Sign up (takes 30 seconds). 2. Fill in the keywords to be monitored. 3. Each week you receive an email with patent applications related to your keywords. Start now! - Receive info on patent apps like Optical window for an intracorporeal device or other areas of interest. ### Previous Patent Application: Endoscopic vision system Next Patent Application: Remote tissue retraction device Industry Class: Surgery ### FreshPatents.com Support Thank you for viewing the Optical window for an intracorporeal device patent info. IP-related news and info Results in 3.70979 seconds Other interesting Feshpatents.com categories: Electronics: Semiconductor , Audio , Illumination , Connectors , Crypto , |
||
