The present invention relates to an improved method and apparatus for infusing a catheter into a patient's artery or vein to enable a care giver to withdraw from or supply liquid nutrients, medicine and the like directly into the patient's blood stream. Additionally the invention is directed to an instrument and method for obtaining a biopsy.
Needles, with a flexible catheter slidably mounted over their distal ends, are typically used to insert or infuse a catheter into a patient's vein or artery, with the needle being withdrawn once the catheter is in place. This procedure is fraught with problems. Arteries and veins, (“vessels”), are not typically immobile but tend to move as the needle is advanced toward them. Without the nurse or doctor (installer) knowing the precise location of the vessel, in real time, the procedure often resolves itself into a trial and error situation with success being problematic. In addition, even when the installer has successfully engaged the targeted vessel with the needle, a successful outcome is not assured. While the needle may have entered the vessel, so that blood can be seen at the proximal end of the needle, the catheter may still be outside of the vessel; also, the needle and catheter may have passed entirely through the vessel.
Guide wires, inserted through the needle, have been used to guide a catheter into the interior of a vein or vessel. However, this technique is of little help to the installer in finding an elusive vessel. In addition, ultrasound equipment has been used to aid the installer in guiding a needle to an illusive vessel. None of these techniques take the place of a human eye's ability to accurately steer a needle/catheter to and into a targeted vessel.
There is a need for the installer to see, in real time, the position of the tip of the needle relative to the targeted vessel. In my research I have found the optical coherence tomography (“OCT), a cutting edge technology, is capable of providing an image in front of a probe through several millimeters of tissue. The use of this technology in conjunction with a needle/catheter will enable an installer to visualize the tissue, including a targeted vessel positioned 2 to 3 mm in front of the needle tip, thereby largely eliminating the hit or miss procedures of the prior art.
Various methods have and are being used to assist a surgeon in finding and subsequently positioning a conventional biopsy needle in an appropriate place to enable a sample of the suspected abnormal growth to be removed for analysis. Also, such conventional needles and procedures leave something to be desired in determining the best places to take a sample or samples of an oddly-shaped growth. Similar to the conventional catheter infusion technique discussed above there is a need for the surgeon to be able to see the size and shape of the abnormal growth from the perspective of the front of the biopsy needle. To this end I have determined that the use of an OCT probe positioned at the front of a biopsy needle would be a great benefit to s surgeon.
A method, in accordance with the present invention, includes the steps of first providing a needle with an OCT probe located at its distal end or tip with a fiber optic cable extending from the probe along the interior of the needle and exiting from near the proximal end of the needle. The exiting end of the cable is connected to an optical end electronics module capable of supplying light to, receiving reflected light from the probe, and deciphering the information contained in the reflected light. The output of the module is fed to a computer and monitor for providing the installer with an image of the tissue immediately in front of the needle.
Second, a catheter is inserted over the needle so that the distal end of the catheter is positioned near the tip of the needle. Third, the needle and catheter, so assembled, are inserted into a patient adjacent the targeted artery or vein. Fourth, while viewing the displayed image in front of the needle, the needle and catheter is guided into the targeted vessel. Fifth, the needle is withdrawn leaving the catheter in place.
An improved biopsy needle, in accordance with this invention, comprises a double lumen or channel needle with one channel being arranged to accommodate the removal of a sample of the targeted growth. An OCT probe is positioned adjacent the distal end or tip of the other channel with an optical fiber cable extending through and exiting adjacent the proximal end of the needle. An optical and electronics module is connected to the exiting end of the cable for supplying light to, receiving reflected light from the probe and deciphering the reflected light to provide a real time image of the tissue positioned 2 to 3 mm in front of the needle.
a and 8b are simple diagrammatic views with
Referring now to
The OCT probe may include a gradient index lens, (GRIN) or other suitable optics to direct light onto and receive reflected light from the tissue immediately in front of the needle. The module 16 supplies light to and receives the reflected light from the OCT probe. Such OCT systems for imaging in nontransparent tissue are described in several treatises. See for example, the book “Optical Coherence Tomography”, published by Elsevier and authored by Dr. Mark E Brezinski, and in particular chapter 6 and the light delivery devices in subchapter 6.7. Also see the Biomedical Optical Imaging book edited by James G. Fujimoto and Daniel L. Farkas (Oxford University Press) and in particular pages 170 and 171 for schematics of OCT probes (referred to as a catheter on page 172) and related optics and electronics for powering the probe and deciphering the information obtained there from to provide an image several millimeters deep into the tissue in front of the probe.
An article in Vol. 47, No. 8 Suppl.C, Apr. 18, 2006, of the Journal of the American College of Cardiology entitled “Plaque Characterization With Optical Coherence Tomography” by Debra Stamper et al describes and depicts in schematic form an OCT imaging engine including an OCT probe, (referred to as a catheter) of only 0.017 inches in diameter made by Lightlab of Westford, Mass.
In use the care giver, while viewing an image of the tissue 2 or 3 mm in front of the tip 12a of the needle via the monitor, inserts the needle and catheter into a patient's tissue adjacent the targeted vein or artery, as is illustrated in
Referring now to
Referring now to
It should noted that the OCT probe and optics cable may be formed as an integral part of the needles eliminating the need for a separate channel.
This application is based on and claims priority of U.S. Provisional Application No. 61/632,352, filed on Jan. 23, 2012, the contents of which are incorporated herein by reference.