WO2002078560A1

WO2002078560A1 - Method and means for locating and signalling a non-palpable lesion in soft tissues

Info

Publication number: WO2002078560A1
Application number: PCT/IB2002/000926
Authority: WO
Inventors: Jacopo Nori
Original assignee: H.S. Hospital Service S.P.A.
Priority date: 2001-03-30
Filing date: 2002-03-26
Publication date: 2002-10-10
Also published as: ITMO20010060A0; ITMO20010060A1

Abstract

A method for identifying and indicating a non-palpable lesion in soft tissue comprises injecting marker means into said tissue via a hollow needle along a route leafing to said lesion, said marker means comprising a macromolecular substance detectable by echography or magnetic resonance. Means for identifying and indicating a non-palpable lesion in soft tissue comprise marker means injectable into said soft tissue along a route leading to said lesion, said marker means comprising a macromolecular substance detectable by echography or magnetic resonance. Means for identifying and indicating a non-palpable lesion in soft tissue comprise needle means with a hollow cylindrical body (1) and a tip (2) releasably fixed to an end of said body (1) and provided with fixing means (7) suitable for fixing into said soft tissue.

Description

Method and means for locating and signalling a non-palpable lesion in soft tissues

The present invention relates to a method and means for identifying and indicating lesions in soft tissue, in particular non-palpable breast lesions.

From prior art it is known identifying and indicating non- palpable lesions in soft tissue by inserting a cannula needle, i.e. a hollow needle, into the tissue and identifying the position of the needle through known display techniques such as mammography, radiography, etc. When the needle has reached the lesion a metal wire is fed through the needle until the wire reaches the previously identified lesion and the metal wire is left in position whereas the cannula needle is extracted, whereby the wire is a reference for a surgeon, who must then operate on the lesion. The end of the wire in contact with the identified lesion generally has fixing means which remain fixed to the tissue in the zone of said lesion. This system has the drawback that the wire may break or be moved due to movements of the patient's body which cause the tissue to move in the zone in which the wire was inserted thus making said wire useless as a reference. Moreover, the metal wire inside the soft tissue may be made visible by mammography but cannot be detected by other types of examination such as echography or magnetic resonance . This makes the use of the metal wire as a reference not very versatile.

Moreover, the metal wire is disagreeable to the patient and for this reason it can be left in position only for short periods; the metal wire therefore has to be inserted only shortly before a surgical intervention. Another system used to indicate a lesion identified in soft tissue provides progressively extracting a hollow needle and simultaneously injecting a preparation containing sterile carbon, after identification of the lesion and positioning of a hollow needle with its tip in the lesion. The sterile carbon injected along the needle route as far as the identified lesion helps the surgeon to more easily visually identify the route to follow to surgically reach said lesion. Marking with sterile carbon, has the advantage of remaining for a long time and of not causing the patient discomfort, so that it can be carried out considerably in advance of the surgeon' s intervention.

However, marking with active carbon is visible only to the naked eye and cannot be detected through imaging methods such as mammography, echography, magnetic resonance, etc. Moreover, when active carbon is injected great care has to be taken to inject it uniformly, whilst the cannula needle is being withdrawn, to avoid the risk that a major portion of the route of the cannula needle is not marked with the active carbon, which would make the marking substantially unusable.

From prior art it is also known using, instead of active carbon, radiological contrast means such as Tecnezio. However, this system involves numerous organisational problems inasmuch as Technezio has to be injected shortly before the surgical intervention and also requires close coordination between the department of Nuclear Medicine and the departments of Radiology and Surgery. This system cannot therefore be used if a certain time, for example, a few days, must elapse between marking and the surgical intervention. Moreover, Tecnezio marking can be detected only by an appropriate probe but cannot be seen with the naked eye or with imaging methods. The object of the present invention is to provide a method and means for identifying non-palpable lesions in soft tissue which enable certain identification and marking of said lesion which is clear, lasting, visible to the naked eye and which can be detected by any imaging method.

According to a first aspect of the present invention a method is provided for identifying and indicating a non-palpable lesion in soft tissue comprising inserting a hollow needle into said soft tissue, identifying the position of the needle in said soft tissue, further inserting said needle until the tip of the needle reaches said lesion, extracting the needle from said soft tissue, injecting marker means, during said extraction, characterised in that said marker means comprise a macromolecular substance detectable by echography or magnetic resonance.

According to another aspect of the present invention means for identifying and indicating a non-palpable lesion in soft tissue are provided, comprising marker means injectable into said soft tissue along a route leading to said lesion, characterised in that said marker means comprise a macromolecular substance detectable by echography or magnetic resonance. The marker means can also comprise a colouring substance such as active carbon and/or contrast means which can be detected by radiological examination.

Owing to the invention, a durable trace is left along the route of the needle through the tissue to the zone affected by the lesion, in particular due to the presence of the colouring means and the macromolecular substance, said trace being detectable both by the naked eye and by all imaging methods. According to a further aspect of the present invention a needle usable for identifying and indicating a non-palpable lesion in soft tissue is provided, comprising an internally hollow cylindrical body, characterised in that said hollow cylindrical body ends in a tip which is releasably connected to the hollow cylindrical body and is provided with fixing means suitable for being fixed onto said soft tissue. The needle according to the invention significantly facilitates execution of the so-called sentinel lymph node technique which is used in surgical interventions on breast tumours in women. This technique consists of injecting, before the surgical intervention, contrast means which can be detected radiologically, for example a Tecnezio solution, on the tumour lesion to identify, by means of a mammoscintigraphy, the axillary lymph node through which the tumour is drained. After identifying the lymph node, the surgeon removes it so that it can be analysed in order to identify the type of tumour and to decide whether the other axillary lymph nodes have to be removed too.

This technique thus requires the previously identified breast lesion to be located afresh on the day of the surgical intervention so that the radiological contrast means can injected into said breast lesion. This causes the patient physical discomfort and requires close coordination between the departments of Nuclear Medicine, Radiology and Surgery. The use of the needle according to the invention enables the removable tip of the needle to be left inside the lesion when the breast lesion is identified because when the needle is removed from the patient' s body the tip has been positioned inside said lesion and the fixing means of the tip of the needle ensure that the tip remains fixed to the tissue and detaches itself from the needle when the needle is extracted, said tip thus remains inside the patient' s body at the identified lesion and thus acts as an accurate reference for injection of the radiological contrast means when the sentinel lymph node technique is carried out. The invention will be now described hereinafter, in a mere exemplifying and not restrictive way, with reference to the enclosed drawings, in which:

Figure 1 is a longitudinal schematic section of a needle according to the invention: Figure 2 is a section like the one of Figure 1, which shows the tip detached from the body of the needle;

Figure 3 is a section like the one of Figure 2, which shows a variation of the needle according to the invention; Figure 4 is a longitudinal schematic section like the one of Figure 1, which shows a construction variation of the tip of the needle according to the invention;

Figure 5 is a section like the one of Figure 4, which shows the tip detached from the body of the needle;

Figure 6 is a section like the one of Figure 3 which shows the application of said construction variation of the tip of the needle to the variation of the needle shown in Figure 3. The method for identifying and indicating a non-palpable lesion in soft tissue according to the invention comprises inserting a hollow needle into said soft tissue, identifying the position of the needle in said soft tissue, further inserting said needle until the tip of the needle reaches said lesion, extracting the needle from said soft tissue, during said extracting the needle, injecting marker means which comprise a macromolecular substance detectable by echography or magnetic resonance. The macromolecular substance is preferably a synthetic human albumen. The colouring means may be sterile carbon. The marker means may also comprise contrast means which can be detected radiologically.

The use of a macromolecular substance in said marker means, possibly in conjunction with a colouring substance and contrast means which can be detected radiologically, enables certain identification of the route which the surgeon has to follow to reach said lesion. The macromolecular substance in fact leaves a durable trace along the route of the needle inserted as far as the zone of said lesion, which trace can easily be detected by imaging methods such as echography and magnetic resonance. Moreover, if the macromolecular substance is combined with colouring means, said route can be easily seen, also because the macromolecular substance facilitates the persistence of the colouring substance along said route. Finally, if said marker means also comprise contrasting means which can be detected radiologically said route can, if necessary, be detected by a radiological examination. In Figures 1 to 6 a needle is shown which can be used to carry out the method according to the invention and which is particularly suitable for performing the sentinel lymph node technique, described above.

In Figure 1, the reference 1 indicates the hollow cylindrical body of the needle according to the invention ending in a tip 2 comprising a shank 3 suitable for being inserted into the cavity 4 of the cylindrical body 1. The shank 3 comprises a cavity 5, communicating, at one end thereof, with the cavity 4 of the cylindrical body 1 and, at the other end, with the inside of the tip 2, said tip being also hollow. The tip 2 comprises holes 6 which enable the hollow interior of the tip 2 to communicate with the exterior. The tip 2 also has fixing means comprising elastic tabs 7 which are connected at one end thereof to the side surface of the tip 2. When the needle is inserted into soft tissue inside the patient's body the elastic tabs 7 are compressed by said tissue against the side surface of the tip 2 of the needle. When the needle is extracted from the patient's body the tabs 7 fix onto the surrounding tissue and are spread out towards the exterior to prevent the tip 2 from being extracted together with the needle. The shank 5 of the tip 2 is extracted from the cavity 4 of the cylindrical body 1 and the tip 2 separates from the cylindrical body 1 and remains trapped inside the patient' s body in the position in which it was inserted.

In Figure 3 a variation of the needle according to the invention is shown, in which a tube 8, preferably in radioopaque material, is associated to the shank 5 of the tip 2. When the body 1 of the needle is extracted from the patient's body the tube 8 remains fixed to the tip 2 of the needle. The length of the tube 8 is such that after the body 1 of the needle has been extracted from the patient's body an end of the tube 8 protrudes and can be used to inject, for example, contrast means which can be detected radiologically for performing the sentinel lymph node technique, at the tumour lesion in which the tip 2 of the needle has been inserted.

The tip 2 of the needle is preferably made with biologically compatible material, i.e. with a material which does not cause undesirable irritations or allergic reactions with the patient's tissues; e.g. the tip 2 of the needle can be made from a titanium steel alloy known under the commercial name "Nitinol" or from AINSI 304 biocompatible steel alloy. In Figures 4, 5 and 6 a construction variation of the tip 2a of the needle is shown. According to this construction variation, the internally hollow tip 2a has elastic tabs 7a which are fixed at one end thereof to the base of the tip 2a. Inserting the elastic tabs 7a in the cavity 4 of the body 1 of the needle makes the elastic tabs 7a press against the internal surface of the cavity 4 and thereby anchors tip 2a to the body 1 of the needle. Like tip 2, tip 2a has holes 6, which enable the hollow interior of the tip 2 to communicate with the exterior. After the needle has been inserted into the patient' s body, the tip 2a can be released from the body 1 by pushing the tip 2a out of the body 1 through pusher means (not shown) insertable into said cavity 4. Owing to the thrust exerted on the tip 2a by said pushing means the tabs 7 protrude from the cavity 4 and elastically separate as shown in Figure 4 so anchoring the tip 2a to the surrounding tissue. In Figure 6 a needle according to the invention is shown having a tip 2a, to the base of which a tube 8 in radioopaque material is fixed as already described with reference to Figure 3. The tube 8 communicates with the hollow interior of the tip 2a and can also be used as a pusher to separate the tip 2a from the body 1 of the needle, after the latter has been inserted into the body of the patient.

The needle according to the invention can also be used, as it has already been said, to mark the route for reaching the tumour lesion. In this case, after the tip 2, 2a of the needle inserted into the patient's body has reached the zone affected by the tumour lesion, extraction of the body 1 of the needle is started and simultaneously the marker means are injected according to the invention. Alternatively, said marker means can also be injected through a common hypodermic needle after the tip of the needle has reached the tumour lesion and during extraction of the needle.

In practice, materials, dimensions and details of execution may be different from, but technically equivalent to those described without departing from the scope of the present invention.

Claims

1. Method for identifying and indicating a non-palpable lesion in soft tissue comprising inserting needle means into said soft tissue, identifying the position of said needle means in said soft tissue, further inserting said needle means into said soft tissue until one tip thereof reaches said lesion, extracting said needle means from said soft tissue injecting marker means during said extracting, characterised in that said marker means comprise a macromolecular substance detectable by echography or magnetic resonance.

2. Method according to claim 1, wherein said macromolecular substance comprises synthetic human albumen.

3. Method according to claim 1, or 2, wherein said marker means comprise colouring means.

4. Method according to claim 3, wherein said colouring means are sterile carbon.

5. Method according to one of claims 1 to 4, wherein said marker means further comprise contrast means detectable by radiological examination.

6. Means for identifying and indicating a non-palpable lesion in soft tissue comprising marker means injectable into said soft tissue along a route which leads to said lesion, characterised in that said marker means comprise a macromolecular substance detectable by echography or magnetic resonance.

7. Means according to claim 6, wherein said macromolecular substance comprises synthetic human albumen.

8. Means according to claims 6, or 7, wherein said marker means comprise colouring means.

9. Means according to claim 8, wherein said colouring means are sterile carbon.

10. Means according to one of claims 6 to 9, wherein said marker means further comprise contrast means detectable by radiological examination.

11. Means for identifying and indicating a non-palpable lesion in soft tissue comprising needle means suitable for being inserted into said soft tissue said needle means comprising a hollow cylindrical body (1) , characterised in that said needle means further comprise a tip (2; 2a) releasably fixed to one end of said body (1) and provided with fixing means (7) suitable for fixing into said soft tissue.

12. Means according to claim 11, wherein said tip (2; 2a) is provided with a shank (3) insertable into a cavity (4) of said body (1) .

13 . Means according to claim 12 , wherein said shank (3) is provided with a longitudinal through cavity (5) .

14. Means according to claim 13, wherein said tip (2; 2a) is provided with an internal cavity.

15. Means according to claim 14, wherein said internal cavity communicates with said through longitudinal cavity (5) of said shank (3) .

16. Means according to claims 14, or 15, wherein said tip (2; 2a) has holes (6) communicating with said internal cavity.

17. Means according to one of claims 11 to 16, wherein said fixing means comprise elastically deformable tab means (7) .

18. Means according to claim 17, wherein said tab means (7) are fixed at one end thereof to the external surface of said tip (2; 2a) .

19. Means according to claim 17, wherein said tab means (7) are fixed at one end thereof to the base of said tip (2; 2a) .

20. Means according to one of claims 11 to 19, wherein said tip (2; 2a) is connected to tubular means (8) insertable into said cavity (4) of said body (1) .

21. Means according to claim 20, wherein said tubular means (8) have an end communicating with said longitudinal cavity (5) .

22. Means according to claim 21, wherein said end is inserted into said longitudinal cavity (5) .

23. Means according to claim 20, wherein said tubular means (8) are fixed at one end of the base of said tip (2a) and communicate with the internal cavity of said tip (2a) .

24. Means according to one of claims 20 to 23, wherein said tubular means have a greater length than the length of said body (1) and have a lesser diameter than the internal diameter of said hollow cylindrical body (1) .

25. Means according to one of claims 11 to 24, wherein said tip (2; 2a) is made from biocompatible material.

26. Means according to claim 25, wherein said biocompatible material is a titanium steel alloy.

27. Means according to claim 25, wherein said biocompatible material is an AINSI 304 steel alloy.