Abstract:
Biopsy needles equipped with fibres ( 20 ) allow tissue inspection to diagnoses. In order to allow detailed inspection side looking fibres should also be integrated around the needle. These fibres might be embedded in a transparent medium ( 18 ) to avoid direct contact of the sharp edges of the fibre to the tissue. A biopsy needle having such embedded fibres as well as a method for manufacturing said biopsy needle, based on curable transparent liquid, is provided by the invention.

Description:
FIELD OF THE INVENTION 
       [0001]    The invention generally relates to a biopsy device. Particularly, the invention relates to a biopsy device comprising a shaft with fibres for optical inspection. 
       BACKGROUND OF THE INVENTION 
       [0002]    As shown in  FIG. 1 , optical fibres might be integrated in the shaft wall of a biopsy device. With these fibres optical inspection of the tissue around the device becomes possible. Light from emitting fibres is coupled out through a small hole in the outer surface of the device in a direction perpendicular to the axis of rotation of the device. This light will scatter in the tissue. The same or other fibres, also integrated in the device and in the vicinity of the emitting fibre, are used for collecting the scattered light. Both emitting and collecting fibres are mounted parallel to the axis of rotation of the device. Because the main direction of the emitted or collected light travels in a direction perpendicular to the axis of rotation of the device, the plane of the tip of the fibre shall have an inclination of 45° relative to its axis of rotation, as shown in  FIG. 1 . 
         [0003]    However, the following problems or disadvantages exist in the prior art. In the outer surface of the biopsy needle transparent windows must be present through which the light is coupled out into the tissue or through which the light is collected from the tissue. These windows also must act as a seal to avoid penetrating of liquid and particles of the tissue into the device. Furthermore, these seals itself and the junction between fibre and seal may not obstruct the passage of the light from the fibre into the tissue and vice versa. The manufacturing and the assembly of this kind of seals is difficult, because of the small dimensions and because various fibres have to be incorporated. 
       SUMMARY OF THE INVENTION 
       [0004]    It is an object of the invention, to provide a biopsy device, the manufacturing of which is simplified and, thus, the costs of manufacturing are reduced. 
         [0005]    This object is solved by the subject matter of the respective independent claims. Further exemplary embodiments are described in the depend claims. 
         [0006]    Generally, a biopsy device according to the invention, comprises an elongate shaft with a wall surrounding an inner space, and with a fibre having a tip and allowing the emitting and/or receiving of light, wherein the wall comprises a first material being transparent, and wherein the tip of the fibre is embedded in the first material. 
         [0007]    According to a first embodiment of the invention, the wall is formed completely from the first material, i.e., the complete wall of the biopsy device is transparent and the fibre or a plurality of fibres are embedded in the wall, such that the fibres will not obstruct any object introduced into the shaft. Furthermore, no edge or sharp portion of the fibres will came in contact with tissue, when a biopsy procedure is performed. 
         [0008]    According to a second embodiment of the invention, the wall of the shaft of the biopsy device further comprises a second material forming an outer tube being not transparent, wherein holes are provided in the outer tube. 
         [0009]    As one aspect of the embodiments, the tip of the fibre might comprise an end surface which is inclined relative to the axis of the elongate shaft. The advantage of the inclined surface is that the light emitted through the fibre, will be directed in a desired direction, for example, perpendicular to the axis of the shaft. By way of such an arrangement, also tissue at the side of the shaft might be inspected. 
         [0010]    Further, a reflective layer might be provided at the inclined end surface of the tip of the fibre, to improve the reflection of the emitted/received light to the desired direction. 
         [0011]    Alternatively, an air bubble might be provided in the first material, located at the inclined end surface of the tip of the fibre, or reflective particles might be provided in front of the tip of the fibre, wherein the reflective particles might be provided in a separately formed droplet or layer. 
         [0012]    Accordingly, the method for manufacturing a biopsy device according to the invention bases on the following steps:
   1. Applying optical fibres to the surface of an inner tube. Each fibre comprises an inclined plane at the tip of the fibre, which may be covered with a reflective layer.   2. Suspend transparent liquid around these fibres, in such a way, that they are fully covered.   3. In case the inclined plane of the tip of the fibre is not covered with a reflective layer, take measures that this plane is not in contact with the transparent liquid, for example, by way of an air bubble.   4. Cure the transparent liquid to become solid.   
 
         [0017]    In step 3 a mould can be used to form the outer surface of the needle. It is also possible to dip in transparent liquid. 
         [0018]    In step 4 UV curable liquid can be used, when the transition from liquid into solid is obtained by UV illumination of the liquid, for instance Vitralit. 
         [0019]    Also liquids can be used, consisting of two components, where the transition from liquid into solid is obtained by a chemical reaction during a certain time span, for instance Araldit. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0020]    In the following, the invention will be described by way of preferred embodiments with respect to the figures, wherein: 
           [0021]      FIG. 1  shows a sectional view of a shaft of a biopsy device according to the prior art, having a hole in the outer surface of the shaft. 
           [0022]      FIG. 2  shows a sectional view of a first embodiment of a biopsy device according to the invention. 
           [0023]      FIG. 3  shows three detail views of different variants of the tip of a fibre embedded in a transparent medium. 
           [0024]      FIG. 4  shows three detail views of different variants of the tip of a fibre according to a second embodiment of the invention. 
       
    
    
     DETAILED DESCRIPTION OF EMBODIMENTS 
       [0025]    As illustrated in  FIG. 2 , a shaft of a biopsy device according to the invention includes a construction where both emitting and receiving fibres are embedded in a transparent material forming the shaft. This material itself forms the outside surface of the biopsy device. 
         [0026]    Accordingly, the shaft of the biopsy device comprises an inner space  10 , a wall formed by a transparent material  18 , at least one fibre  20  for emitting and/or receiving light. In the figures, the light emitted through a fibre, is illustrated as arrows  30 . 
         [0027]    The inner space  10  may also be a conventional needle such as a hollow metal needle for biopsy procedures, around which the transparent material  18  may be present. 
         [0028]    For unobstructed passage of the light from the fibre  20  through the transparent material  18  into the tissue and vice versa the tip of the fibre  20  must be embedded in the transparent material. 
         [0029]    To obtain maximum reflection of the light at the surface of the incled plane of the fibre tip, one of the following measure shall be taken. 
         [0030]    According to the variant A, shown in  FIG. 3 , a reflective layer is applied to the outer surface of the inclined plane (b) at the tip of the fibre  20 . 
         [0031]    According to the variant B, shown in  FIG. 3 , an air bubble (c) is provided in the transparent material  18  (also indicated with a) in such a way that there is only air in contact with the outer surface of the inclined plane and not the transparent curable material. 
         [0032]    According to variant C of the first embodiment, shown in  FIG. 3 , first a curable droplet or layer, containing reflective particles (indicated with d), is provided, covering the inclined end of the fibre. In this way the inclined end of the fibre is covered with reflective particles leading to oblique outcoupling of light. Subsequently, a curable layer (a) which is fully transparent is applied to make the outer surface fully flat without sharp edges. 
         [0033]    Since the wall of the shaft is fully transparent, it is, in principle, possible to emit the light from a tip of a fibre in any direction relative to the axis of the shaft. Thus, the light should be emitted from the tip of a respective fibre to a predefined direction, i.e. with a predefined angle, to make sure that a user of the device will know which tissue located around or inside the biopsy device, is inspected. 
         [0034]    According to an exemplary embodiment, there is provided a plurality of fibres, each of which has a predefined inclination to the axis of the shaft, wherein the inclination might be different from one fibre to another. It is also possible that a tip of a fibre is located at the end of the shaft such that the light will be emitted in the direction of the axis of the shaft, i.e. to the front. 
         [0035]    According to the second embodiment of the invention, the biopsy needle comprises an outer tube  14  made of non-transparent material, in the surface of which small holes  16  are manufactured, as shown in  FIG. 4 . 
         [0036]    The emitting and receiving fibres are fixed relative to an inner space  10  in such a way that the tips of the fibres  20  are just below the holes  16 . To avoid penetrating of liquid and particles of the tissue into the device, the holes  16  in the outer tube  14  are filled with a material  18  (also indicated as a), transparent for the emitted and collected light. 
         [0037]    For unobstructed passage of the light from the fibre  20  through the hole  16 , also the tip of the fibre must be embedded in the transparent material and the same measures might be taken as described with respect to the first embodiment of the invention. 
         [0038]    According to variant D, as shown in  FIG. 4 , a reflective layer is applied to the outer surface of the inclined plane (b). 
         [0039]    According to variant E, shown in  FIG. 4 , an air bubble (c) is provided in the medium (a) in such a way that there is only air in contact with the outer surface of the inclined plane and not the transparent curable layer (a). 
         [0040]    According to variant F of the second embodiment, first a curable droplet or layer, containing reflective particles, indicated with (d), is provided, covering the inclined end of the fibre  20 . In this way the inclined end of the fibre is covered with reflective particles leading to oblique outcoupling of light. A curable layer (a) which is fully transparent is then applied to make the outer surface of the shaft fully flat without sharp edges. 
         [0041]    It should be noted, that the biopsy device according to the invention might be a biopsy needle itself, wherein the inner space is adapted to receive tissue which is intended to be analyzed. On the other hand side, the biopsy device might be a canula which will be introduced into a body to lead a biopsy needle, and through which the biopsy needle might be introduced into the body, to perform the actual biopsy. 
         [0042]    While the invention has been illustrated and described in detail in the drawings and foregoing description, such illustration and description are to be considered illustrative or exemplary and. not restrictive; the invention is not limited to the disclosed embodiments. 
         [0043]    Other variations to the disclosed embodiments can be understood and effected by those skilled in the art in practicing the claimed invention, from a study of the drawings, the disclosure, and the appended claims. In the claims, the word “comprising” does not exclude other elements or steps, and the indefinite article “a” or “an” does not exclude a plurality. The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measured cannot be used to advantage. Any reference signs in the claims should not be construed as limiting the scope.