BIOPSY APPARATUS AND METHOD
BACKGROUND
1. Technical Field
The present disclosure relates to instruments and methods used for obtaining tissue samples. More particularly, the present disclosure relates to minimally invasive biopsy instruments and methods for obtaining tissue samples.
2. Background of Related Art
It is often necessary to sample tissue in order to diagnose and treat patients suspected of having cancerous tumors, pre-malignant conditions and other diseases or disorders. Typically, in the case of suspected cancerous tissue, when the physician establishes by means of procedures such as palpation, x-ray or ultrasound imaging that suspicious conditions exist, a biopsy is performed to determine whether the cells are cancerous. Biopsy may be done by an open or percutaneous technique. Open biopsy removes the entire mass (excisional biopsy) or a part of the mass (incisional biopsy). Percutaneous biopsy on the other hand is usually done with a needle-like instrument and may be either a fine needle aspiration (FNA) or a core biopsy. In core biopsy, as the term suggests, a core or fragment tissue is obtained for histologic examination which may be done via frozen section or paraffin section.
The type of biopsy utilized depends in large part on the circumstances present with respect to the patient and no single procedure is ideal for all cases. Core biopsy, however, is extremely useful in a number of conditions and is being used more frequently.
Intact tissue from the organ or lesion is preferred by medical personnel in order to arrive at a definitive diagnosis regarding the patient's condition. In most cases only part of the organ or lesion need be sampled. The portions of tissue extracted must be indicative of the organ or lesion as a whole. In the past, to obtain adequate tissue from organs or lesions within the body, surgery was performed so as to reliably locate, identify and remove the tissue. With present technology, medical imaging equipment such as stereotactic x-ray, fluoroscopy, computer tomography, ultrasound, nuclear medicine and magnetic resonance imaging, may be used. These technologies make it possible to identify small abnormalities even deep within the body. However, definitive tissue characterization still requires obtaining adequate tissue samples to characterize the histology of the organ or lesion. The introduction of stereotactic guided percutaneous breast biopsies offered alternatives to open surgical breast biopsy. With time, these guidance systems have become more accurate and easier to use. Biopsy guns were introduced for use in conjunction with these guidance systems. Accurate placement of the biopsy guns was important to obtain useful biopsy information because only one small core could be obtained per insertion at any one location. To sample the lesion thoroughly, many separate insertions of the instrument had to be made.
Biopsy procedures may benefit from larger tissue samples being taken, for example, tissue samples as large as 10 mm across. Many of the prior art devices required multiple punctures into the breast or organ in order to obtain the necessary samples. This practice is both tedious and time consuming.
One further solution to obtain a larger tissue sample is to utilize a device capable of taking multiple tissue samples with a single insertion of an instrument. Generally, such biopsy instruments extract a sample of tissue from a tissue mass by either drawing a tissue sample into a hollow needle via an external vacuum source or by severing and containing a tissue sample within a notch formed on a stylet. Such devices generally contemplate advancing a hollow needle into a tissue mass and applying a vacuum force to draw a sample into the needle and hold the same therein while the tissue is extracted.
A continuing need exists for percutaneous biopsy apparatus and methods which can reliably extract adequate biopsy sample(s) with a single insertion of the biopsy instrument.
SUMMARY
A biopsy apparatus is provided that employs an outer hollow knife tube cannula with a distal end cutter, a trocar rod and a tissue basket tube. The trocar and tissue basket tube are configured to be removably positioned within the knife tube. The trocar rod has a piercing tip on its distal end. The tissue basket tube contains a tissue basket for obtaining and transporting tissue samples that is in fluid communication with a vacuum source.
A biopsy method is provided wherein a biopsy apparatus employs an outer hollow knife tube with a distal end cutter and an inner trocar rod member to penetrate a patient's tissue and position the apparatus at least partially within the tissue to be sampled. The trocar rod is removed from the hollow knife tube and the tissue basket tube is positioned in the distal end of the hollow knife tube and at least partially within the tissue to be sampled.
The hollow tube is withdrawn to at least partially expose the tissue basket to the tissue to be sampled. A vacuum is applied to assist the natural prolapse of tissue into the tissue port and the distal end cutter of hollow knife tube is repositioned over the issue basket to sever a tissue sample. The tissue basket tube transports the tissue sample through the hollow knife tube.
The presently disclosed biopsy apparatus and method, together with attendant advantages, will be best understood by reference to the following detailed description of the invention when used in conjunction with the figures below.
BRIEF DESCRIPTION OF THE DRAWINGS
Preferred embodiments of the presently disclosed biopsy apparatus are described herein with reference to the drawings, wherein: FIG. 1 is a perspective view of one embodiment of the knife tube, trocar rod, and tissue basket tube biopsy apparatus in accordance with the present disclosure;
FIG. 2 is a longitudinal cross sectional view of one embodiment of the knife tube, and trocar rod as constructed in accordance with the present disclosure in a first position;
FIG. 3 is a longitudinal cross sectional view of one embodiment of the knife tube and tissue basket constructed in accordance with the present disclosure in a second position;
FIG. 4 is a longitudinal cross sectional view of one embodiment of the knife tube and tissue basket constructed in accordance with the present disclosure in a third position; and FIG. 5 is a longitudinal cross sectional view of one embodiment of the knife tube, and tissue basket constructed in accordance with the present disclosure in a fourth position.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS Referring now in specific detail to the drawings in which like referenced numerals identify similar or identical elements throughout the several views, and initially to FIG. 1 , the preferred configuration of the knife tube, trocar rod, and tissue basket biopsy apparatus 100 (hereinafter referred to as "biopsy apparatus 100") includes a knife tube 10, a trocar rod 20, and a tissue basket tube 30. For purposes of clarity, only the details of the working distal ends 12, 22, and 32 are illustrated in detail. The proximal ends 14, 24, and 34 may be attached to a suitable handle or actuator to facilitate operation of biopsy apparatus 100 or any of the other biopsy apparatus embodiments or configuration disclosed herein. For example, biopsy apparatus 100 may include a housing wherein knife tube 10, trocar rod 20, and tissue basket tube 30 are housed. The housing may include suitable known driving and actuating mechanisms. In one embodiment a penetrating member such as the knife tube and trocar rod may be rapidly movable into position at the target tissue location by a suitable drive mechanism, such as, for example, potential energy devices, drive motors, pneumatic devices, or any other suitable drive mechanism. Knife tube 10 includes a distal end 12 and a proximal end 14 wherein tubular wall
16, distal end 12 and proximal end 14 define a lumen concentric to the axis "X." Distal end 12 contains a cutting edge 15 that has the function of piercing the outer tissue of the patient and when in position within the desired tissue portion to be sampled, edge 15 severs tissue samples in combination with tissue basket tube 30. Knife tube 10 is preferably fabricated from a stainless steel, but it could be made of medical grade plastic or composite molded to contain an integral metal cutting edge 15. Cutting edge 15 is preferably fabricated from stainless steel by a suitable process, such as stamping or metal injection molding.
Trocar rod 20 includes a distal end 22 with a piercing tip or knife blade tip 25 and a proximal end 24. Trocar 20 is sealingly engaged and removably positioned within knife tube 10 and can be repositioned about the longitudinal axis "X." Trocar 20 is a solid rod injection molded of a polycarbonate, or similarly suitable type material in which knife blade tip 25 on distal end 22. Knife blade tip 25 is preferably fabricated of stainless steel.
Tissue basket tube 30 includes a distal end 32 and a proximal end 34. Tissue basket tube 30 has a tubular wall 36 that defines at least one tissue port 35 near distal end 32. Tissue basket tube 30 is sealingly engaged and removably positioned within knife tube 10 and concentric with longitudinal axis "X." Tissue port 35 also partially defines a tissue basket 37 in combination with inside walls 38 and a floor 40. Floor 40 further defines a plurality of holes 39 that are in fluid communication with a vacuum passageway 41 and a vacuum source (not shown). Tissue basket tube 30 is preferably fabricated from a suitable medical grade metal, but it could alternatively be fabricated from a suitable polycarbonate type material.
Referring now to FIG. 2, biopsy apparatus 100 or any of the other biopsy apparatus embodiments or configuration disclosed herein may be inserted by suitable known techniques, for example, by motor driver or spring fired mechanisms. Alternatively, biopsy apparatus 100 may be inserted manually. In either arrangement, biopsy apparatus 100 or • any of the other biopsy apparatus embodiments or configuration disclosed herein may be configured as a hand held apparatus or as part of a frame mounted device. An example of such a device is an image guided positioning apparatus such as a stereotactic imaging machine. Any suitable imaging modality may be used to guide biopsy apparatus to the target tissue.
Biopsy apparatus 100 in a first position is in a first position as shown with trocar rod 20 concentrically positioned and sealingly engaged within knife tube 10. Biopsy apparatus 100 utilizing cutting edge 15 and knife blade tip 25 pierces a patient in the first position and is at least partially positioned within a tissue portion 50. Referring now to FIG. 3, biopsy apparatus 100 is in a second position wherein knife tube 10 is maintained in position at least partially within tissue portion 50 while trocar rod 20 is removed and replaced by tissue basket tube 30. Tissue basket tube 30 is sealingly engaged with knife tube 10 and the at least one tissue basket 37 is positioned in the portion of distal end of knife tube 10 that is positioned at least partially within the tissue to be sampled. In FIG. 4, biopsy apparatus 100 is in a third position wherein knife tube 10 is withdrawn proximally to at least partially expose tissue port 35 and tissue basket 37. The prolapse of tissue portion 50 into tissue port 35 is augmented by the application of the vacuum communicated from the vacuum source through passageway 41 to holes 45 defined in the floor 40 of tissue basket 37.
Referring now to FIG. 5, biopsy apparatus 100 is in a fourth position wherein tissue basket tube 30 is withdrawing proximally and the distal end cutting edge 15 of knife tube 10 has severed a tissue sample 55 from tissue portion 50. Severed tissue sample 55 is retained in tissue basket 37 and withdrawn proximally through knife tube 10. To take additional tissue samples, knife tube 10 is repositioned at least partially within the tissue to be sampled and tissue basket tube 30 is repositioned in knife tube 10 so as to be positioned at least partially within the tissue to be sampled using the same or a different combination of longitudinal position or radial orientation.
Although the illustrative embodiments of the present disclosure have been described herein with reference to the accompanying drawings, it is to be understood that the disclosure is not limited to those precise embodiments, and that various other changes and modifications may be affected therein by one skilled in the art without departing from the scope or spirit of the disclosure. All such changes and modifications are intended to be included within the scope of the appended claims.