Abstract:
A filtration station for capturing small to medium sized tissue fragments in fluid for histological processing. The filtration station allows tissue to be filtered onto foam in a cassette or into a biopsy bag with speed, excellent tissue recovery and convenient fixative collection for recycling or disposal. The present invention combines two normally separate filtration stations into one station for more convenient filtration of tissue into two widely used filter media while also reducing exposure to harmful vapors.

Description:
BACKGROUND OF THE INVENTION  
         [0001]    This invention relates to the general art of analysis of tissue samples, and in particular to obtaining, handling and processing small to medium sized tissue samples in fluid for histological processing.  
           [0002]    Various disease processes, particularly tumors, require a histologic diagnosis. Cell types of a tumor are generally determined by a pathologist&#39;s examination of a histologic sample of the tumor. There are a number of devices that have been fashioned to actually perform the act of taking tissue samples. In many cases, these samples are very small and difficult to retrieve and process. The small tissue fragments originating from various biopsy procedures are generally rinsed into a specimen container with a preservative effluent, such as 10% formalin, to prevent loss of the sample, dehydration of the sample, and contamination of the sample during harvesting, storage and transport.  
           [0003]    For actual histological diagnosis, the tissue specimen must be separated from the effluent. The smallness of the samples make it very difficult and time consuming to separate and process the samples in the laboratory. Upon separation, it is desirable to immobilize the pieces of tissue within some device such as sponge or in filter paper biopsy bag which resembles tea bag to prevent them from becoming lost during processing.  
         SUMMARY OF THE INVENTION  
         [0004]    The present invention provides a filtration station for capturing small to medium sized tissue fragments in fluid for histological processing. The filtration station allows tissue to be filtered into either foam in a cassette or into a biopsy bag, with speed, excellent tissue recovery and convenient fixative collection for recycling or disposal. The primary feature of the present invention is the combination of two normally separate filtration stations into one station for more convenient filtration of tissue into two widely used filter media while also reducing exposure to harmful vapors. Other novel features of the invention include: (i) combination of two holders for two commonly used filtration media (foam and biopsy bags; (ii) unique holder for using biopsy foam, thereby speeding up use and permitting capture of effluent for recycling; (iii) unique holder for biopsy bags, thereby speeding up use and permitting capture of effluent for recycling; (iv) unique funnel for use with both the foam holder and the biopsy bag holder; and (v) unique features of both media holders and the funnel permit the same funnel to direct specimens into either holder.  
           [0005]    In one embodiment of the invention, the present invention provides two separate substations within one structure. The single structure is comprised of a container with a lid. One substation is comprised of a foam funnel cassette well with drainage holes within the lid. The well is sized to hold a standard histology processing cassette. The substation provides for filtration of specimens through a foam pad within the cassette and the container provides a reservoir for the suspending fluids to go into while tissue is being filtered out by the foam pad in the cassette. A funnel is also included to provide a pouring transition means for a sample tissue effluent solution from a specimen container to the foam pad.  
           [0006]    The other substation provides a holder for biopsy bags, i.e., small filter bags which resemble tea bags. The holder is comprised of an open cylindrical shape with a bottom integrated with a section of the lid. The lid portion at the bottom of the cylinder is perforated. The cylinder holds the biopsy bags and the funnel holds and seals the biopsy bag during filtration. The drainage holes direct the filtration fluid into the container. The same funnel may be used for either substation.  
           [0007]    In another embodiment of the invention, a more compact unit is provided with one substation implemented on one side of the lid and the other substation implemented on the opposite side of the lid.  
           [0008]    The present invention provides a faster and more convenient filter separation of samples within an effluent. The present invention also provides a convenient effluent recovery for recycling and disposal purposes. There is also reduced exposure to laboratory personnel to vapors from toxic effluents. The present invention also provides the availability of selecting efficient use of one of two common histology filter types depending on specimen needs in one station using shared tools such as one funnel for both filter types.  
           [0009]    These together with other objects of the invention, along with various features of novelty which characterize the invention, are pointed out with particularity in the claims annexed hereto and forming a part of this disclosure. For a better understanding of the invention, its operating advantages and the specific objects attained by its uses, reference should be had to the accompanying drawings and descriptive matter in which there is illustrated a preferred embodiment of the invention. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0010]    [0010]FIG. 1 is a front perspective view of one embodiment of the invention.  
         [0011]    [0011]FIGS. 2A and 2B are front perspective views of another embodiment of the invention.  
         [0012]    [0012]FIG. 3 is a top view of the invention embodiment shown in FIG. 1.  
         [0013]    [0013]FIG. 4 is a side view of the lid shown in FIG. 3.  
         [0014]    [0014]FIG. 5 is a top view of the invention embodiment shown in FIG. 2A.  
         [0015]    [0015]FIG. 6 is a side view of the lid shown in FIG. 5.  
         [0016]    [0016]FIG. 7 is a top view of the funnel of the invention.  
         [0017]    [0017]FIG. 8 is a side view of the funnel of FIG. 7. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0018]    Referring to the drawings in detail wherein like elements are indicated by like numerals, there is shown in FIG. 1 a biological filtration station embodiment  1  constructed according to the principles of the present invention. The filtration station  1  is comprised of a reservoir container  10  having a bottom  11  from which generally cylindrical side walls  12  extend vertically upward terminating in an open top  14 , said container  10  being generally cylindrical in shape, said container  10  having the longitudinal axis generally perpendicular to the container bottom  11 , said container  10  having a lid  15  removably attached to said side walls  12  for covering the interior  13  of said container  10 .  
         [0019]    The lid  15  is round and generally planar having a top surface  16  and a bottom surface  17 , said bottom surface  17  enclosing the container interior  13  when the lid  15  affixed to the container top  14 . The lid  15  may be made from an acrylic resin such as sold under the trademark, PLEXIGLAS. In this embodiment of the invention the lid  15  has a perimeter  18  with a 90 groove  19  formed therein resulting in the top surface  16  having a larger diameter than the bottom surface  17 .  
         [0020]    The lid top surface  16  has a generally rectangular cassette well  20  formed therein. The rectangular well  20  is sized to hold a standard histology processing cassette  3 . The bottom  21  of the rectangular well  20  has a series of holes  22  formed therein, said holes  22  extending through the lid  15  and opening onto the lid bottom surface  17 .  
         [0021]    The lid top surface  16  also has a generally round well  25  formed therein. The round well  25  has a bottom  26  from which generally a hollow cylindrical holder  28  extends vertically upward, said cylinder  28  having a longitudinal axis generally perpendicular to the round well bottom  26 . The holder  28  has an open top  29 . The round well bottom  26  has a series of holes  27  formed therein, said holes  27  extending through the lid  15  and opening onto the lid bottom surface  17 .  
         [0022]    The filtration station  1  is also comprised of a funnel  30  having an open bottom  31  from which cylindrical main body side walls  32  extend vertically upward, said funnel  30  being generally cylindrical in shape and having a longitudinal axis generally perpendicular to the funnel bottom  31 , said funnel side walls  32  terminating in an open funnel top  33 . The funnel bottom  31  is beveled inward resulting in a smaller diameter at the funnel bottom  31  then along the side walls  32  of the main body  35 . The funnel  30  has an upper portion  34  comprising approximately  25 % of the upper longitudinal length of the funnel  30  and terminating at the funnel top  33 . The diameter of the upper portion  34  increases approximately 30% over the diameter of the main body  35 .  
         [0023]    In an alternate embodiment of the invention a filtration station  2  is comprised of a reservoir container  10  having a bottom  11  from which generally cylindrical side walls  12  extend vertically upward, said container  10  being generally cylindrical in shape, said container  10  having the longitudinal axis generally perpendicular to the container bottom  11 , said container  10  having a lid  40  removably attached to said side walls  12  for covering the interior  13  of said container  10 .  
         [0024]    The lid  40  is round and generally planar having a first surface  40  and an opposite second surface  42 . The lid  40  may be made from an acrylic resin such as sold under the trademark, PLEXIGLAS. In this embodiment of the invention the lid  40  has a perimeter  43  with central protruding flange  44  forming a first  900  groove  45  and a second  900  groove  46  resulting in the flange  44  having a larger diameter than the either of the surfaces  41 ,  42 .  
         [0025]    The lid first surface  41  also has a generally round well  25  formed therein. The round well  25  has a bottom  26  from which generally a hollow cylindrical holder  28  extends vertically upward, said cylinder  28  having a longitudinal axis generally perpendicular to the round well bottom  26 . The holder  28  has an open top  29 . The round well bottom  26  has a series of holes  27  formed therein, said holes  27  extending through the lid  40  and opening onto the lid second surface  42 .  
         [0026]    The lid second surface  42  has a generally rectangular cassette well  20  formed therein. The rectangular well  20  is sized to hold a standard histology processing cassette  3 . The bottom  21  of the rectangular well  20  has the round well holes  27  opening therein.  
         [0027]    The filtration station  2  is also comprised of a funnel  30  having an open bottom  31  from which cylindrical main body side walls  32  extend vertically upward, said funnel  30  being generally cylindrical in shape and having a longitudinal axis generally perpendicular to the funnel bottom  31 , said funnel side walls  32  terminating in an open funnel top  33 . The funnel bottom  31  is beveled inward resulting in a smaller diameter at the funnel bottom  31  then along the side walls  32  of the main body  35 . The funnel  30  has an upper portion  34  comprising approximately  25 % of the upper longitudinal length of the funnel  30  and terminating at the funnel top  33 . The diameter of the upper portion  34  increases approximately 30% over the diameter of the main body  35 .  
         [0028]    In operation, the rectangular well  20  in both filter stations  1 ,  2  is used to hold a standard histology processing cassette  3  with a foam pad  4  and the round well  25  is used for a biopsy bag  5 .  
         [0029]    The rectangular well  20  provides solid support for the cassette  3  during the filtration process. The rectangular well bottom holes  22  provides free flow of the preservative effluent  7  into the container interior  13 . The funnel  30  provides a pouring transition means for a sample tissue effluent solution from a specimen container  6  onto the cassette foam pad  4 . The funnel&#39;s steep side walls  32  minimizes adhesion of tissue fragments to the side walls  32 . The funnel upper portion  34  is large enough to permit pouring directly into the funnel top  33  from specimen containers  6  of approximately 30 to 90 cc&#39;s. The funnel  30  is tapered at its bottom  31  thereby ensuring a fit between cassette sides. The tapered funnel bottom  31  also compresses the foam edges forming a seal trapping suspended tissue fragments on the foam pad  4  while the effluent  7  passes through the foam pad  4  and well perforations  22  into the reservoir  13 . The rectangular well walls  23  and drainage holes  22  direct the filtration fluid  7  into the container interior  13  preventing spilling over the top surface  16 ,  41 ,  42  and perimeter  18 ,  43  the container lid  15 ,  40 .  
         [0030]    The holder  28  provides solid support for biopsy bags  5  during the filtration process. The round well bottom holes  27  provide free flow of effluent  7  into the container interior  13 . The funnel  30  provides a pouring transition means for a sample tissue effluent solution from a specimen container  6  into the biopsy bag  5 . The tapered funnel bottom  31  is fitted into the holder top  33  thereby locking the biopsy bag  5  in place and preventing biopsy bag collapse. The fit of the well and funnel bottom forms a seal trapping the open portion of the biopsy bag preventing escape of fluid and tissue, as well as preventing the bag from prematurely separating from the funnel. The same funnel  30  may be used for either substation  20 ,  25 .  
         [0031]    The second embodiment of the filtration station  2 , provides a more compact unit with one substation  20  implemented on one side  42  of the lid  40  and the other substation  25  implemented on the opposite side  41  of the lid  40 . The substation  20  or  25  not being used will be on the lid side  42  or  41  covering and facing the container interior  13 .  
         [0032]    It is understood that the above-described embodiments are merely illustrative of the application. Other embodiments may be readily devised by those skilled in the art which will embody the principles of the invention and fall within the spirit and scope thereof.