Patent Publication Number: US-2023149686-A1

Title: Venous Access Port Assembly with X-Ray Discernable Indicia

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application is a continuation application of 16/851,459, filed Apr. 17, 2020, which is a continuation application of 15/441,762, filed Feb. 24, 2017, now U.S. Pat. No. 10,639,465, issued May 5, 2020, which is a continuation application of, and claims the benefit of, co-pending U.S. patent application Ser. No. 12/175,270, filed Jul. 17, 2008, now U.S. Pat. No. 9,610,432, issued Apr. 4, 2017, which claims the benefit of U.S. Provisional Patent Application Ser. No. 60/961,160, filed Jul. 19, 2007, the disclosures of which are incorporated by reference in their entirety. 
    
    
     FIELD OF THE INVENTION 
     This relates to the field of medical devices and more particularly to venous access ports for the infusion of fluids into the patient and/or withdrawal of fluids from the patient. 
     BACKGROUND OF THE INVENTION 
     Venous access ports for the infusion and/or withdrawal of fluids from a patient are well-known, secured to the proximal end of an implanted catheter. These ports are typically used for drug infusion or for withdrawal of small amounts of blood, where large flows of fluid are not required. The ports are assemblies of a needle-impenetrable housing with a discharge port in fluid communication with the catheter and the reservoir within the port housing, and provide a subcutaneous self-sealing septum that defines an access site for multiple needle sticks through the covering skin tissue of the patient, through the septum and into the reservoir, without the need to continuously search for new access sites. Examples of such ports are disclosed, for example, in U.S. Pat. Nos. 4,704,103; 4,762,517; 4,778,452; 5,185,003; 5,213,574; 5,637,102; and 5,833,654. In U.S. Pat. No. 5,833,654 is set forth a dual chamber port assembly having a metal casing as a liner in one of the chambers of the port assembly. 
     It is desired to provide a venous access port assembly that provides for a radiologist, radiology technologist, nurse and ultimately a medical practitioner to be able to discern an important property of the port assembly after the port assembly has been implanted into a patient. 
     BRIEF SUMMARY OF THE INVENTION 
     The present invention is related to a venous access port having a housing and a septum, providing an interior reservoir and a passageway extending from the reservoir through a stem of a discharge port to establish fluid communication with a proximal end of a catheter lumen to which the port assembly is secured prior to placement of the assembly into a patient. 
     The port may optionally have more than one reservoir and associated septum. The invention is the incorporation of X-ray discernable indicia onto a venous access port that is discernible under X-ray examination to provide information concerning the nature or key attribute of the venous access port, so that the practitioner, subsequent to the date of implantation thereof, can determine that nature or key attribute under X-ray examination. One such key attribute in particular would be, for example, that where the venous access port is rated to be used for power injection, such as used for contrast fluid injection during a contrast enhanced computed tomography, the letters “CT” (for “computed tomography) would be provided on the port assembly in such a manner that they are radiographically visible. The attribute in this example is the property of the port&#39;s being adapted to withstand high pressures that are used for injection of contrast fluid into a patient, and the letters “CT” would be understood in medical practice to indicate that the port is suitable for the high pressure injection of contrast fluid. 
     In the preferred embodiment, a reservoir lining of radiopaque material such as titanium, includes cutouts such as of letters “CT” (although other indicia may be utilized) through the body of the lining, with the cutouts being radiographically visible. The lining for the reservoir is contained within the port housing and includes an aperture through the side wall for fluid communication with a discharge stem of the port assembly, establishing fluid communication with a catheter sealingly and securely affixed to the discharge stem of the assembly. The reservoir lining of titanium provides protection against penetration by a needle when it is inserted through the septum of the port assembly for injection of fluid into the chamber. The letters “CT” are readable from exterior of the patient in an X-ray. The lining may have several such sets of cutouts located at various locations about the lining&#39;s side wall and/or in the bottom wall thereof. The cutouts preferably are substantially narrow for exposing therethrough only a minimum amount of plastic of the surrounding housing. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The accompanying drawings, which are incorporated herein and constitute part of this specification, illustrate the presently preferred embodiments of the invention, and, together with the general description given above and the detailed description given below, serve to explain the features of the invention. In the drawings: 
         FIGS.  1  and  2    are an isometric view and an exploded view, respectively, of the venous access port assembly containing the present invention; 
         FIG.  3    is an isometric view of a reservoir lining of the present invention defining X-ray discernable indicia; 
         FIG.  4    is an enlarged view of portion of the lining of  FIG.  3    illustrating the cutout indicia provided by the lining; and 
         FIGS.  5  and  6    are cross-section views of the port of  FIGS.  1  and  2   . 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Certain terminology is used herein for convenience only and is not to be taken as a limitation on the present invention. The terms “distal” and “proximal” refer, respectively, to directions closer to and away from the insertion tip of a catheter in an implantable catheter assembly. The terminology includes the words specifically mentioned, derivatives thereof and words of similar import. The embodiments illustrated below are not intended to be exhaustive or to limit the invention to the precise form disclosed. These embodiments are chosen and described to best explain the principle of the invention and its application and practical use and to enable others skilled in the art to best utilize the invention. 
     Venous access port assembly  10  of  FIGS.  1 ,  2 ,  5  and  6    includes a housing  12  and a septum  14 , with a discharge stem  16  extending from a distal end  18  of the port assembly  10  to be attached securely and sealingly to the proximal end of a catheter (not shown). Cap  20  of housing  12  secures to housing base  22  to in turn secure septum  14  in position in the port assembly  10  in a manner that exposes the top surface of the septum for needle insertion. A passageway  24  (see  FIGS.  5  and  6   ) extends from an interior reservoir  26  to the distal tip opening  28  of discharge stem  16 . A recess  30  is seen to be provided along both sides of discharge stem  16 , facilitating insertion of the discharge stem  16  into the catheter lumen and providing a clearance for a locking sleeve or clamp (not shown) utilized to compress the catheter lumen wall against the exterior surface of the discharge port  16  for assured sealed connection of the catheter with the port assembly  10 . 
     With reference now to  FIGS.  2  to  4   , showing reservoir lining  50  of the present invention, lining  50  is cup-shaped and is inserted into well  32  of housing base  22  beneath septum  14 , and secured therewithin. Lining  50  is made of needle-impenetrable material such as metal, which may be titanium or stainless steel, and its side wall  52  and bottom wall  54  protects the side walls  34  and bottom wall  36  of housing base  22  defining well  32 , from being penetrated by a needle (not shown) inserted into and through septum  14  for injection of fluids into reservoir  26  or withdrawal of blood therefrom. An aperture  56  near or at the bottom of side wall  52 , in alignment with a corresponding aperture  38  of housing base  22 , establishes fluid communication with passageway  24  of discharge stem  16  for fluid to pass between the reservoir  26  and the catheter and thus the patient. Discharge stem  16  may be a metal component such as titanium or stainless steel which would extend through aperture  38  of the housing base  22 , to preferably be welded to lining  50 . 
     In accordance with the present invention, the X-ray discernable indicia are cutouts  60  formed through the body of lining  50 , shown as the alphabetical letters “CT”. The letters “CT” are visible when the X-ray of the patient is viewed, readable from outside the lining  50  and are easily discerned by the radiologist or technologist. In lining  50 , preferably a plurality of sets of cutout indicia  60 , 62  are provided equi-angularly spaced about the circumference of the side wall  52  and through bottom wall  54  to assure that the indicia appear in the X-ray irrespective of the angular location at which the X-ray is taken. With particular reference to  FIG.  4   , it is preferable that the width of each cutout slot  58  of the indicia or letters be as narrow as possible but still be discernable by X-ray; the narrowness of the slots  58  minimizes any possibility that a needle inserted through the septum could penetrate through a slot of a cutout by chance, thus harming the patient and resulting in injection of fluid directly into the tissue surrounding the port. The width of each cutout slot  58  would thus preferably be less wide than the diameter of a needle. The set of cutout indicia  62  through the bottom wall may be dimensionally larger as a set, but still with narrow slot width. Centering of the cutout indicia  62  along the bottom wall  54  positions the indicia directly beneath the reservoir and septum, minimizes any obscuring thereof by the structure of the venous access port assembly, and the indicia may also be easily discernable should the port assembly be at an angle from the horizontal plane of the X-ray. 
     It will be appreciated by those skilled in the art that changes could be made to the embodiments described above without departing from the broad inventive concept thereof. It is understood, therefore, that this invention is not limited to the particular embodiments disclosed, but it is intended to cover modifications within the spirit and scope of the present invention as defined by the appended claims.