Abstract:
There is provided a table for positioning a patient for a medical procedure on a breast, the table comprising: a supporting platform having a back end for supporting the patient&#39;s legs and a front end for supporting the patient&#39;s torso while the patient is in a prone position, and a cavity at the front end for allowing the breast and a surrounding axilla region to be pendantly suspended therethrough; wherein the table has a lateral depression for allowing an arm and a shoulder adjacent to the breast to extend over the table and be lowered such that skin from the axilla region is relaxed and extends through the cavity, and the table is configured to provide the depression on each side of the cavity in a position where a right shoulder would be when a right breast.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     The application is cross-referenced to U.S. patent application entitled “Method and Apparatus for Optical Imaging” filed simultaneously herewith and with agent docket number 15818-35us. 
    
    
     FIELD OF THE INVENTION 
     The invention relates to a table for positioning a patient when performing breast imaging, scanning, and biopsies. More specifically, it relates to features of the table that can improve the volume of tissue captured by the imaging/scanning apparatus and the comfort of the patient throughout the medical procedure. 
     BACKGROUND OF THE INVENTION 
     Certain medical procedures, such as breast biopsies, must be done with the patient in a face down prone position. There are also imaging and scanning procedures that are done in a prone position. There are several variations of tables that currently exist for these procedures. 
     For example, U.S. Pat. No. 5,569,266 issued to Siczek discloses a magnetic resonance imaging device useful for guiding a medical instrument, such as a biopsy needle. The patient is positioned on a table top having an opening through which the patient&#39;s breast pendulantly projects. The pendulant breast is immobilized by a basket. The drawbacks of this table are in the volume of tissue that can project through the basket and the general comfort of the patient. 
     Another example is U.S. Pat. No. 5,609,152 issued to Pellegrino et al. for a prone position stereotactic mammography needle biopsy apparatus and a method for using the same. The table disclosed by Pellegrino et al. comprises a space for an arm to come down beside the table. A drawback of this design is that there is no room for the axilla region to be accessed. This is a serious drawback as a large proportion of tumors in breast cancer are found in the tissue in the axilla region. 
     Moreover, since new imaging and scanning systems are coming out that require patients to lie on a table for a substantial amount of time, there is a need to improve the general comfort of the patient for medical procedures that are sometimes unpleasant. 
     SUMMARY OF THE INVENTION 
     Accordingly, an object of the present invention is to overcome the drawbacks of the prior art. 
     Yet another object of the present invention is to improve the general comfort of the patient for medical procedures on breasts. 
     According to a first broad aspect of the present invention, there is provided a table for positioning a patient for a medical procedure on a breast, the table comprising: a supporting platform having a back end for supporting the patient&#39;s legs and a front end for supporting the patient&#39;s torso while the patient is in a prone position, and a cavity at the front end for allowing the breast and a surrounding axilla region to be pendantly suspended therethrough; wherein the table has a lateral depression for allowing an arm and a shoulder adjacent to the breast to extend over the table and be lowered such that skin from the axilla region is relaxed and extends through the cavity, and the table is configured to provide the depression on each side of the cavity in a position where a right shoulder would be when a right breast is in the cavity and a left shoulder would be when a left breast is in the cavity. 
     Preferably, a lateral depression is provided on one side of the table and a movable portion of the table rotates to the other side of the table so as to provide the depression on the opposite side when an opposite breast is placed in the cavity. The rotation is done with a rotating plate engaged into the supporting platform, and in conjunction with a headrest that also rotates laterally. Also preferably, the cavity is adjustable in size and position. 
     According to a second broad aspect of the present invention, there is provided a table for positioning a patient for a medical procedure on a breast, the table comprising: a supporting platform having a back end for supporting the patient&#39;s legs and a front end for supporting the patient&#39;s torso while the patient is in a prone position, and a cavity at the front end for allowing the breast and a surrounding axilla region to be pendantly suspended therethrough; wherein the cavity is substantially pear-shaped such that a larger portion is for the breast and a narrower portion is for the axilla region, and the cavity is positioned at an angle such that the narrower portion faces an outer side of the supporting platform. 
     Preferably, the table comprises a lateral depression that is provided on one side of the table and a movable portion of the table rotates to the other side of the table so as to provide the depression on the opposite side when an opposite breast is placed in the cavity. The rotation is done with a rotating plate engaged into the supporting platform, and in conjunction with a headrest that also rotates laterally. Also preferably, the pear-shaped cavity is rotated such that it is always angled in a way that the narrower portion faces the outer edge of the table. 
     According to a third broad aspect of the present invention, there is provided a method for positioning a patient on a table for a medical procedure on a breast, the method comprising: placing the patient face down in a prone position on a supporting platform such that the patient&#39;s legs and torso are supported; providing a cavity in the supporting platform such that the breast and a surrounding axilla region is pendantly suspended therethrough; extending an arm and a shoulder adjacent to the breast over the table such that skin from the axilla region is relaxed and extends through the cavity, wherein a left arm and shoulder is extended over the table on a left side of the cavity when a left breast is in the cavity and a right arm and shoulder is extended over the table on a right side of the cavity when a right breast is in the cavity. 
     Preferably, the arm extended over the table is adjusted in height and in position on an armrest provided for the elbow and forearm to rest on. The head and feet are also adjusted in height for comfort purposes. The cavity is substantially pear-shaped and is rotated such that when a left breast is in the cavity, the narrower portion is facing the left side of the table and when a right breast is in the cavity, the narrower portion is facing the right side of the table. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       These and other features, aspects and advantages of the present invention will become better understood with regard to the following description and accompanying drawings wherein: 
         FIG. 1  is a preferred embodiment of the table in accordance with the present invention; 
         FIG. 2  is an alternative embodiment of the table in accordance with the present invention; 
         FIG. 3  is another embodiment of the table in accordance with the present invention; and 
         FIG. 4  is a flowchart of the method in accordance with the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
       FIG. 1  shows a preferred embodiment for the table. The table comprises a supporting platform  10  having a back end and a front end for supporting the patient&#39;s legs and torso, respectively. The patient lies face down on the table, slightly off center, and places a breast inside the cavity  11  present in the front end of the supporting platform  10 . The breast is pendantly suspended within the cavity  11 . The table has a lateral depression for allowing the arm and shoulder adjacent to the breast to extend over the table. 
     In the embodiment shown in  FIG. 1 , the cavity is substantially pear-shaped. 
     That is to mean that the cavity comprises a wide and a narrow portion, such that the wide portion is for the breast to be suspended therethrough and the narrow portion is for the axilla region adjacent to the breast to be suspended therethrough. The shape of the cavity is such that a maximum possible volume of tissue can be exposed below the table. This way, access to the regions of interest is facilitated. 
     The table shown in  FIG. 1  can be used to perform a medical procedure on a left or a right breast. The cavity is present in a disc plate  12  in the front end of the supporting platform  10 . For imaging of the left breast, the cavity  11  must be rotated such that the narrow portion is facing towards the left side of the table in order to receive the left axilla region of the patient. The rotation of the disc  12  can be done manually or remotely with a set of controls. The headrest  13  must also be moved such that the space provided for the arm of the patient is on the left side of the table. As can be seen from the figure, the headrest  13  is independent of the supporting platform  10  and can be slid to the opposite side. This can also be done either manually or remotely with a set of controls. 
     In optical imaging, it is desirable to obtain a simple geometry of the object being imaged such that mathematical algorithms can be used to produce the actual image. One way to do this is to use a pair of parallel plates that compress the breast into a rectangular slab and produce a parallelepiped. the plates are also used to stabilize the breast and prevent motion during the imaging. When stabilizing plates are used to compress the breasts and scan an image, a circular shape is ideal for the cavity when the compression is at 0° and 90° with respect to the table. However, a pear-shaped or oval cavity is preferred when compressing the breast at around 45° with respect to the table in order to properly access the tissue in the axilla region. Therefore, the disc plate  12  seen in  FIG. 1  is removable and can be replaced by a similar disc plate with a cavity that is circular. Furthermore, the circular cavities may vary in size to accommodate breasts of different sizes. 
     An armrest  14  can also be seen in the figure. The armrest  14  is below the level of the table and serves to support the elbow and forearm of the patient that is adjacent to the breast suspended in the cavity  11 . The armrest  14  is adjustable in height to accommodate patients of different sizes and place the shoulder at the ideal level such that the patient is comfortable enough to remain in a fixed position for a substantially long amount of time. The supporting platform  10  is also slightly inclined such that the legs and feet are at a lower level than the head and torso. This is also for patient comfort and provides the patient with a better sense of stability in the prone position. 
       FIG. 2  shows an alternative embodiment to providing a space for the arm on a left and a right side of the table. A supporting platform  10  is still present to support the legs and torso of the patient. However, a large disc  15  is engaged into the supporting platform  10 . Within this large disc  15  is a smaller disc  16  with the cavity  11  for the breast. The larger disc  15  rotates such that the opening for the breast is on the left or the right side of the table, depending on the breast in question. The cavity  11  for the breast is closer to the side than in the previous embodiment, shown in FIG.  1 . 
     The design of the smaller disc  16  is such that the breast can be scanned or imaged in at least three directions. Two parallel, vertical, stabilizing plates compress the breast at 0° (the plates move along the axes of the table), 90° (the plates move perpendicular to the axes of the table), and 45° (the plates move diagonally). The plates, which are seen as two compression members in the figure, form a rectangular cavity and can accommodate breasts of varying sizes. The two plates can move inwards for compression, as well as up, down, and rotate with respect to the rest of the platform. The smaller disc  16  is formed of at least two separate pieces that surround the cavity  11 . One of the pieces can be removed to leave a space for the axilla and underarm region, providing a lateral depression on a left or a right side of the table, depending on the position of the larger disc  15 . An armrest  14  is also present to support the forearm and elbow when the axilla region is exposed through the cavity  11 . 
     The design of the larger disc  15  is possible without the smaller disc  16  within it. A regular cavity is present within the larger disc  15 , the cavity being fixed in size and shape. This embodiment can be used for biopsies, wherein it is unnecessary to compress the breast at different angles because images are not being taken of the breast. The biopsy equipment can easily be placed underneath the table and used in conjunction with it. 
     Alternatively, a pear-shaped cavity may be present in the larger disc. The cavity is to be angled at approximately 45° below the horizontal axis of the disc. When the disc is rotated, the cavity is still angled at approximately 45° of the horizontal axis, but on the opposite side of the table. In this case, compression plates may be independent from the table and be provided beneath the table. A space on adjacent to the cavity is to be provided for the arm if the smaller disc plate is not within the larger disc plate. 
       FIG. 3  is a preferred embodiment of the apparatus in accordance with the present invention. From the figure, it can be seen that the supporting platform is not flat, but instead comprises concave and convex curves that are specially designed to increase patient comfort. The central area of the supporting platform is upwardly winged on each side so as to nest the patient within the curve formed by the wings  17 . This creates a sensation of security and eliminates the possibility of rolling off the table. Steps  18  are adjacent to the supporting platform to facilitate mounting of the patient. A banister  19  and handles  20  are also provided to facilitate the mounting and allow the patient to ease herself onto the table comfortably. 
       FIG. 4  corresponds to a flow chart according to the method of the present invention of positioning a patient on a table for a medical procedure on a breast. The first step is to place the patient face down on the supporting platform  30 . A cavity is provided for the breast and axilla region to be pendantly suspended therethrough  32 . An arm and shoulder of the patient adjacent to the breast is extended over the table, wherein a left arm and shoulder is extended over the table on a left side of the cavity when a left breast is in the cavity and a right arm and shoulder is extended over the right side of the table when a right breast is in the cavity  34 . The height of the arm and shoulder is adjusted  36  by adjusting the position of the elbow and forearm on an armrest which is provided below the supporting platform. The arm can be supported by being extended upwards and bent inwards towards the head or simply by being extended parallel to the body. The feet of the patient are also adjusted in height  38  by elevating them using a footrest. The head is then adjusted in height  40  on a headrest. 
     When placing the patient face down on the supporting platform  30 , the patient may be placed in an inclined position such that the feet are lower towards the ground than the upper body. The cavity provided may be substantially pear-shaped such that a narrower portion is for the axilla region and a larger portion is for the breast. This pear-shaped cavity is rotated from a left side of the table to a right side of the table, and vice-versa, such that the narrower portion is always angled towards the outer edge of the table, whether a left or a right breast is in the cavity. 
     It will be understood that numerous modifications thereto will appear to those skilled in the art. Accordingly, the above description and accompanying drawings should be taken as illustrative of the invention and not in a limiting sense. It will further be understood that it is intended to cover any variations, uses, or adaptations of the invention following, in general, the principles of the invention and including such departures from the present disclosure as come within known or customary practice within the art to which the invention pertains and as may be applied to the essential features herein before set forth, and as follows in the scope of the appended claims.