Abstract:
Compression pad for a mammography apparatus comprising a compression plate made of a material transparent to X-rays, and a support by which said pad is configured to be mounted onto a mammography apparatus. The support has an arch shape configured to go over the edge of a compression plate, and said compression plate and said support comprise complementary mechanical means capable of enabling manual locking/unlocking of the support on said plate, in particular for cleaning said plate and said support.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims priority under 35 U.S.C. §119(a)-(d) or (f) to prior-filed, French patent application serial number 0850613, filed on 31 Jan. 2009, which is hereby incorporated by reference in its entirety. 
     STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
     Not Applicable 
     NAMES OF PARTIES TO A JOINT RESEARCH AGREEMENT 
     Not Applicable 
     REFERENCE TO A SEQUENCE LISTING, A TABLE, OR COMPUTER PROGRAM LISTING APPENDIX SUBMITTED ON COMPACT DISC 
     Not Applicable 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The field of the invention relates to medical imaging and more specifically to mammography techniques. It relates in particular to a compression pad for a mammography apparatus, as well as a mammography apparatus including such a pad. 
     2. Description of Related Art 
     Mammography apparatuses conventionally include at least one source of X-rays and a console, arranged opposite said source and configured to receive and support the patient&#39;s breast. This console includes a sensor for sensing X-rays after they have passed through the patient&#39;s breast (array of sensors, film cassette sensitive to X-rays, etc.) and has a compression plate—also called a pad—capable of compressing the breast against the console during imaging. 
     Mammography apparatuses in this sense include, for example, those that the GE Medical Systems company proposes under the name “Senographe” (registered trademark). A detailed example of the structure of such an apparatus is also described in the U.S. Pat. No. 4,979,196. 
     Normally, a compression pad for a mammography apparatus comprises a compression plate made of a material transparent to X-rays, attached to a support, for example in the form of an arch. This support is itself hooked onto means of the mammography apparatus that make it possible to translate the compression pad in the direction of the X-rays, so as to compress the patient&#39;s breast between the console and said pad. 
     Usually, the two parts that constitute, on the one hand, the compression plate made of a material transparent to X-rays and, on the other hand, the support are attached to one another, for example by rivet-type means. 
     BRIEF SUMMARY OF THE INVENTION 
     It is of course desirable to be capable of using compression pads for interventional examinations (biopsies, for example). However, it is possible then that deposits, for example, blood, will spill onto the pad. 
     Compression pads with rivets present problems in this regard, because the rivets can constitute retention areas that are difficult to access when cleaning the pad. 
     An embodiment of the invention therefore provides a compression pad that is easy to clean and that in particular does not have any inaccessible areas. 
     In particular, it provides a pad structure in which the compression pad and its support can easily be separated, and the pad can be disassembled and reassembled manually without requiring complicated handling, and in particular without requiring tools. The compression pad and the support can then easily be cleaned separately, without there being any inaccessible areas on said support and on said plate (at least on the face thereof that contacts the breast). 
     More specifically, an embodiment of the invention provides a compression pad for a mammography apparatus comprising a compression plate made of a material transparent to X-rays and a support by which said pad is configured to be mounted onto a mammography apparatus, wherein the support and the compression plate are capable of being manually separated from one another, particularly for separate cleaning. 
     In particular, in an advantageous embodiment, the support has an arch shape configured to go over the edge of a compression plate, wherein said compression plate and said support are configured to enable manual locking/unlocking of the support on said plate. 
    
    
     
       BRIEF DESCRIPTION OF THE FIGURES 
       Other features and advantages of embodiments of the invention will become clear from the following description, which is purely illustrative and non-limiting and must be read in reference to the appended drawings, in which: 
         FIG. 1  diagrammatically shows a perspective view of a compression pad according to a possible embodiment of the invention, after separation of the support and the transparent compression plate; 
         FIG. 2  shows a side view of a possible embodiment for a portion of the anchoring means on the transparent compression plate of the pad of  FIG. 1 ; 
         FIGS. 3A ,  3 B,  3 C and  3 D show four steps for installing the plastic part of the pad of the preceding figures; 
         FIGS. 4A and 4B  are two side views showing another possible embodiment for the anchoring means; 
         FIG. 5  diagrammatically shows a mammography apparatus comprising a pad according to one of the embodiments of the preceding figures. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     The compression pad shown in  FIG. 1  comprises a compression plate  1  and a support  2  attached thereto. This support  2  is itself suitable for being attached to means forming the lever of the mammography apparatus. 
     The support  2  is, for example, metal, or made of a plastic or composite material and more generally any other material allowing for resistance compatible with its support function. 
     The compression plate  1  is made of a material transparent to X-rays. It is in the form of a base  4 , which has a generally rectangular shape and which extends, on each of its four sides, by an edge  3  that surrounds said base  4 . The edge  3  comprises a front wall  3   a , (at the level of the part of said plate  1  that receives the support  2 ), two lateral walls  3   b  and a rear wall  3   c . The front wall  3   a  and portions of the two lateral walls in the immediate extension of said front walls have a greater height than the rest of said edge  3 , i.e. than the rest of the two lateral walls  3   b  and the rear wall  3   c.    
     In addition, the base  4  has, on the side opposite the front wall  3   a  of the edge  3 , an opening R, for example rectangular, configured in particular to allow the passage of a biopsy tool in a step following the imaging and the analysis of the images by the practitioner. 
     Other opening shapes are of course possible, for example a multitude of circular through-shapes distributed over the surface of the compression plate. 
     The support  2  has a U-arch shape that is configured to go over the edge  3  at the level of the front part of the plate  1 , being pressed on the front wall  3   a  and bordering the lateral walls  3   b  so as to be anchored there. 
     This support  2  has: 
     a base  2   a  that, when the arch is in position on the edge  1   b , is pressed on the higher front wall  3   a , and 
     two lateral branches  2   b  that each comprise notches  5  and  6  that cooperate with complementary means on the lateral walls  3   b  of the edge  3  so as to removably anchor the support  2  on the compression plate. 
     More specifically, on each of the branches  2   b , the notch  5 —which is the one closest to the base  2   a —is a hole formed on said branch  2   b , from a longitudinal section thereof, so as to define a guide ramp  5   a  inclined with respect to the general direction of the branch  2   b , and a recess  5   b  configured to receive a complementary pin  7  on the corresponding lateral wall  3   b.    
     The notches  6  are formed at the ends of the branches  2   a  and have an oblong recess shape  6   a  leading to the end section of the branch  2   b  through an opening  6   b  forming a narrow neck. The main direction of the oblong recesses  6   a  is perpendicular to the direction in which the branches  2   b  extend. 
     These notches  6  are configured to receive locking pins  8  with an oblong or flattened cross-section ( FIG. 2 ) rotatably mounted on the branches  2   b  between a position in which the notches  6  can be introduced on said pins  8  by the narrow neck  6   b  and a locking position in which said pins with an oblong or flattened cross-section  8 , after having been placed in the oblong recesses  6   a , are turned a quarter turn in order to lock the branches  2   b  on the lateral walls  3   b.    
     As regards the anchoring means on the lateral walls  3   b  of the edge  3 , the pins  7  and  8  end with rollers  7   a  and  8   a  to which they are rigidly attached. These rollers are spaced from the lateral wall  3   b  on which they are mounted with a thickness slightly greater than that of the branches  2   b  of the support  2 . 
     These pins  7  and  8  are attached by riveting to the lateral walls  3   b , with a metal plate  10  being provided on each wall  3   b  so as to reinforce said wall and enable said riveting. It is noted that the rivets are located on the side of the compression pad opposite the side that receives the breast, and are protected from any soiling by the edge  3  that surrounds the plate  1 . 
     Other means for attaching the pins  7  and  8  to the walls  3   b  are of course possible: for example, bonding, welding (in the case of compatible materials), snapping, etc. 
     The branches  2   b  end, plumb over the notches  6  and at the level of their sections opposite that where the notches  5  open out, with contact edges  9  perpendicular to the general plane of said branches and lateral walls  3   b.    
     The placement of the support  2  on the plate  1  is performed as follows. 
     The branches  2   b  of the support  2  are presented on the flattened locking pins  8 , by causing said branches  2   b  to glide along the walls  3   b , and introducing the notches  6  on the pins  8  through their narrow-neck openings  6   b , with a certain inclination ( FIG. 3A ). In this step, the rollers  8   a  help to guide the movement of the branches  2   b.    
     Once the notches  6  are in place at the level of the flattened pins  8 , the user tilts the branches  2   b  of the support  2 , coming into contact with the edges  9  and folds back said branches on the lateral walls ( FIG. 3B ). Then, the user continues the movement so as to approach the base  2   a  of the front wall  3   a , by causing the ramps  5   a  of the two branches to glide on the two pins  7 . 
     When the end of the ramp is reached, the user pushes the support  2  so that the base  2   a  is positioned on the front wall  3   a  ( FIG. 3C ). The pin  7  is then housed in the recess  5   b , while the pin with an oblong or flattened cross-section  8  is positioned in the recess  6   a.    
     In a final step, the user turns the rollers  8   a  and their flattened pins  8  one quarter turn, thus locking the support  2  on the compression plate  1 . 
     The compression pad is then ready to be used on the mammography apparatus. 
     Similarly, after use, said compression plate and its support can easily be separated so as to be cleaned separately from one another by performing the reverse of the operations described above. 
     As understood, such a structure no longer has a gap (on its portion in contact with the breast and in particular between the support and the compression plate) that would not be easy to clean after disengagement of the support with respect to the compression plate. 
     Another alternative of the invention is shown in  FIGS. 4A and 4B . In this alternative, the rollers  8   a  that the operator grips to lock the axes  8  have an elongate shape that facilitates the handling by the operator. In addition, when the operator places the support on the compression plate, these gripping rollers  8   a  extend initially substantially perpendicularly with respect to the compression plate  1  and go beyond the edge  3  thereof. In this way, the user is led to fold them back manually, thus necessarily ensuring the locking of the support the plate. 
       FIG. 5  diagrammatically shows a mammography apparatus that includes, on a frame B, an X-ray source  11  mounted on a support  12 . A console  13  housing radiosensitive means (film cassette, electronic array receiver) is arranged opposite the source  11 . 
     The frame B also has a mobile compression arm  14  on which a compression pad of the type described above can be placed (pad  15  in  FIG. 5 ), for example by placing the base  2   a  of the support  2  in a complementary track provided on the arm  14 . This arm  14  is itself powered and is driven, for example by means of a rack system, in a translation movement that moves the pad  15  toward or away from the console  13 , so as to compress or decompress the breast undergoing radiography. 
     With the compression pad structure described above, after use, it is possible to disassemble the pad  15  and to separate the compression support from the compression plate, so that the user can thoroughly clean both parts.