GB2323283A

GB2323283A - Double bore biopsy guiding sheath

Info

Publication number: GB2323283A
Application number: GB9705563A
Authority: GB
Inventors: James Joseph Flanagan
Original assignee: Individual
Current assignee: Individual
Priority date: 1997-03-18
Filing date: 1997-03-18
Publication date: 1998-09-23
Also published as: GB9705563D0

Abstract

The sheath comprises an alloy needle 4 which contains two differently sized bores, the narrower bore 3 being of very small calibre for fitting tightly over a graduated, localisation wire inserted into the tissue of interest and the larger bore 2 allowing insertion of a cutting needle. A stylet 5 may be provided in the larger bore, the sheath then being ready for insertion by threading over the guidewire. After removal of the stylet, the bore is ready to home the cutting needle down onto the target. The sheath is particularly useful in breast tissue biopsy.

Description

DIFFERENTIAL BORE BIOPSY SHEATH This invention relates to a double differential double bore biopsy sheath, which allows accurate removal of suspicious cancer cells from the breast without the need for surgery.

BACKGROUND It has been well known for many years that women may develop small cancers of the breast which cannot be felt by a Surgeon, and therefore cannot be removed. These suspected cancers are frequently only a few mm in size.

Such small tumours are now detected by carrying out a special xray called a mammogram. This is carried out in asymptomatic women, and when suspicious cells are found, they must be removed for histological examination under a microscope since there is no other way of being certain that the cells represent cancer and clearly this important decision must be made. Currently, the method for removing such cells and analysing them under a microscope is for a wire to be inserted into the breast using a special x-ray machine to guide the wire to the area suspected of being cancerous - the target. This wire is enclosed in a cannula, and the whole is inserted into the patient's breast.

When the appropriate level (the target) has been reached, the wire is then pushed out the end of the cannula. A memory in the wire ensures that the memory angle at the end of the wire extends to a fixed angle, thus anchoring it within the breast tissue.

The operator then removes the cannula leaving the wire in the breast.

The patient is then sent for an operation to remove the suspicious cells. The Surgeon uses the wire as a guide to find the abnormal cells and remove the cells and the wire together.

This is a diagnostic operation. If the subsequent histological evaluation under a microscope shows that the patient does not have a cancer, no further action is taken. If the patient does have a cancer, then a second operation needs to be carried out.

Thus, thousands of women in the UK alone undergo a diagnostic operation every year. If some other method could be found for removing the area suspicous of being cancerous without an operation, then a large number of women would have no operation at all (those that were shown not to have cancer) and the remaining large number of women (those that were subsequently shown to have cancer) would only have one operation instead of two. Currently, there is no way of accurately and cheaply removing the cells without subjecting the patient to a diagnostic operation.

According to the present invention, there is provided a double bore biopsy sheath comprising of an alloy needle which contains two bores of different sizes. One bore is of very small calibre, approximately 1/10 mm, and the other bore is approximately 0.7 mm. The smaller bore fits tightly over the localisation wire which has been placed in the patient's breast.

The larger bore allows a cutting needle to be inserted. It has its own stylet fitted (to prevent tissue blocking the whole), but this stylet is removed once the sheath is docked to the target.

A specific embodiment of the invention will now be described by way of example with reference to the accompanying drawing in which Figure I shows in perspective the whole assembly with differential bore biopsy sheath having the cutting needle and guidewire in position. Figure II illustrates the separation of the guidewire and the cutting needle from the differential double bore biopsy sheath. This has a stylet in the larger hole and is ready for insertion to thread over the guidewire (Figure IV).

Figure III demonstrates the double bore biopsy sheath in the breast using the localisation wire to dock the sheath to the target. The stylet is now removed and a channel exists which will home the cutting needle down onto the target. Figure IV shows the type of guidewire with graduated markings which needs to be used. Figure V shows one of the many types of cutting needle that may be used.

Referring to the drawing, it should be understood that the invented differential bore biopsy sheath consists only of the structure demonstrated in Figure II. Here the tip of the needle (1) is pushed through the breast tissue to a depth determined by the graduated guidewire (Figure IV). The graduated guidewire itself is threaded through the thinner bore (3) and up through the shaft of the needle (4) to emerge at the upper part of the needle which will remain above the breast tissue (6). By making calculations from an x-ray taken and by using the graduations on the guidewire, the needle will then travel through the breast tissue down the guidewire and come to rest at a calculated point which will be that level just above the suspected tumour - target (7). The needle (Figure II) is then steadied in this position.

The stylet (5) is withdrawn from the needle, thus ensuring a clear hollow space. The cutting needle (Figure I) is then inserted in the upper larger bore (5) and travels down the shaft of the needle (4) and comes to rest at the lower end of the channel just as it is about to emerge through the end or lower orifice (2). Thus, the needle has been sited just proximal to the suspected cancer - the target (7). It can then be advanced an appropriate amount (as calculated from the graduations on the guidewire Figure IV), and allowed to rest here. The spring loaded cutting needle is then fired and a biopsy of the suspected cancer cells has been taken accurately. This needle is then withdrawn up through the larger channel (2 and 5) and the specimen removed. The procedure may be repeated a number of times. When the procedure is completed, the wire and the differential bore biopsy sheath are removed.

Claims

1. A double differential bore biopsy sheath has been devised which using the aid of a guidewire can be sited close t o suspicious malignant cells - the target (7) in the breast and thus allow a cutting needle to be placed down a second channel in the double bore differential biopsy sheath and allow accurate biopsy of suspicous cells or any part of the breast as desired.

2. A double differential bore biopsy guiding sheath as claimed in claim 1 can also be used to remove substances or insert substances into a part of the breast accurately.

3. A double differential bore biopsy needle as claimed in 1 or 2 wherein its use could be adapted to other parts of the body other than the breast.