Patent Application
20110092920
The present invention relates to a hose system according to the preamble part of claim 1. Such a hose system is known from the products “ohio”, “mississippi” and “missouri” sold by Ulrich GmbH & Co. KG. The invention relates to computed tomography (CT) and magnetic resonance imaging (MRI), and more specifically to injectors for administering contrast agents. CT, originally known as computed axial tomography (CAT or CT scan) and body section roentgenography, is a medical imaging method for generating a three-dimensional image of the internals of an object from a large series of two-dimensional X-ray images taken around a single axis of rotation. The word “tomography” is derived from the Greek tomos (slice) and graphein (to write). CT produces a volume of data which can be manipulated, through a process known as windowing, in order to demonstrate various structures based on their ability to block the X-ray beam. Modern CT scanners allow this volume of data to be reformatted in various planes or even as volumetric (3D) representations of structures.
CT scans rely on intravenously administered contrast agents in order to provide superior image quality. Magnetic resonance imaging (MRI), formerly referred to as magnetic resonance tomography (MRT) is a non-invasive method used to render images of the inside of an object. It is primarily used in medical imaging to demonstrate pathological or other physiological alterations of living tissues. As CT, MRI scanners can generate multiple two-dimensional cross-sections (slices) of tissue and three-dimensional reconstructions. Unlike CT, which uses only X-ray attenuation to generate image contrast, MRI has a long list of properties that may be used to generate image contrast which is created by using a selection of image acquisition parameters that weight signal by T1, T2 or T2*, or no relaxation time (“proton-density images”). T1-weighted and T2-weighted images do not always adequately show the anatomy or pathology. Therefore, as in CT contrast agents may be administered to delineate areas of interest. A contrast agent may be as simple as water, taken orally, for imaging the stomach and small bowel although substances with specific magnetic properties may be used. Most commonly, a paramagnetic contrast agent (usually a gadolinium compound) is given. More recently, superparamagnetic contrast agents (e.g. iron oxide nanoparticles) have become available. Diamagnetic agents such as barium sulfate have been studied for potential use in the gastrointestinal tract, but are less frequently used.
From an injector point of view, there is no big difference between CT and MRI. However, injectors for MRI must not be disturbed by high magnetic fields in the range of 1 T and the injectors must not disturb the magnetic field of the MRI. For the latter reason, injectors for MRI are often powered by batteries or direct current (DC).
There are several injectors on the market. Injectors for CT are e.g. medrad Vistron CT, medrad EnVision CT, medrad Stellant CT, medtron Injektron CT2. medtron Injektron 82CT, medtron Injektron 82 HP, medtron Accutron CT, E-Z-EM Empower CTA, E-Z-EM Empower CT, tyco/LF CT 9000 ADV, tyco/Mallinckrodt Optistat, tyco/Liebel-Flarsheim Opti Vantage DH and Nemoto Dual Shot. Injectors for MRI are for example medrad Spectris Solaris, medtron Injektron MRT, medtron Accutron MR, tyco/Mallinckrodt OPTISTAR LE and Nemoto Sonic Shot 50.
All of the above-identified injectors comprise automatically driven syringes. Medtron Accutron CT and medtron Accutron MR comprise tactile keys for manual piston movement. In some injectors the syringes are disposable. For medrad EnVistron CT reloadable syringes are available. In none of the syringe injectors it is possible to apply several injections consecutively from one contrast agent container. Some syringe injectors comprise two syringes, one for a saline solution, the other one for the contrast agent.
Injectors ulrich ohio tandem, ulrich missouri, ulrich ohio M, ulrich mississippi and Swiss Medical Care CT Exprés come with roll pumps which. pump contrast agent and/or saline solution from at least two different containers into the subject. This architecture enables the application of several injections consecutively from one contrast agent container.
In the following we will focus on the injectors ulrich missouri and ulrich mississippi, which are identical apart from the power supply. Ulrich mississippi is battery-powered which enables MRI application. A fluid flow diagram of the injectors ulrich missouri and ulrich mississippi is shown in
A core clement of the ulrich injectors is a cross-shaped hose system for delivering contrast agent and saline solution from one of a left container 801 for a first contrast agent, a middle container 811 for saline solution and a right container 821 for a second contrast agent to the subject 898. The first and second contrast agents are often identical. Saline solution may be delivered in bottles and pouches. We use container as generic term for bottle and pouch.
The cross-shaped hose system comprises a left contrast agent hose 806, a saline solution hose 816, a right contrast agent hose 826 and a pump hose 832 which are connected by a cross connector 831. Each of the three holders for the three containers 801, 811 and 821 comprise respectively a fixed member 804, 814 and 824, and a swivel member 803, 813 and 823 which are connected by a bolt 805, 815 and 825. For removing nearly empty containers without spilling contrast agent, the swivel members 803 and 823 may be tilted forward and downward by 135° separately. For not spilling saline solution, the swivel member 813 may be tilted leftward and downward by 135°.
The left contrast agent hose 806, the saline solution hose 816 and the right contrast agent hose 826 are each fluidically connected with a piercing needle 802, 812 and 822, respectively, for piercing the rubber stopper of each container 801, 811 and 821. Ultrasonic detectors 807, 817 and 827 monitor when the respective one of the three containers 801, 811 and 821 runs empty. Stop valves 808, 818 and 828 can squeeze off each of the hoses 806, 816 and 826, respectively. Actually, plungers within the injector casing covered by a membrane press the hoses from the back against a glass cover for squeezing the hoses off. Only one of the valves 808, 818 and 828 is open at a time.
The cross connector 831 is fixed by mounting 830 to the injector casing. The pump hose 832 is fixed by mounting 834 and guidances 841 and 842 to the injector casing. The roll pump consists of a pump wheel 850 and wings 843 and 846. The pump wheel 850 comprises three rolls 851, 852 and 853 and three guidances 854, 855 and 856, which have the form of circular arcs. Each of the wings 843 and 846 comprises a circular-arc-shaped abutment 844 and 847, respectively. During operation the pump wheel 850 turns clockwise, whereas the rolls 851, 852 and 853 turn counterclockwise. At least one of the rolls 851, 852 and 853 squeezes the pump hose 832 against one of the abutments 844 and 847 so that no fluid may flow through the squeezed portion of the pump hose 832. When the pump wheel 850 turns clockwise, squeezed portion moves towards the subject 898 thereby pumping fluid towards the subject 898. For inserting and removing the hose system, the wings 843 and 846 may be swung outward and downward by about 45° around pivot 845.
After the roll pump, the pump hose 832 passes through in an air trap 861. Thereafter the pump hose 832 opens up out to a pressure measurement chamber 862 which comprises two measurement membranes through which two pressure sensors 863 and 864 measure the pressure. An error is output if the absolute value of the measured pressure difference between sensors 863 and 864 exceeds a threshold. After the pressure measurement chamber 862 a particle filter 865 and finally a male Luer-Lock 891 protected by a cap 892 follow.
A Subject hose 894 may be connected by a female Luer-Lock 893 to the male Luer-Lock 891. At the other end of the subject hose 894 another male Luer-Lock 895 is fixed which may be either protected by a cap 896 or being connected to a cannula 897 for discharging either a contrast agent or a saline solution into the subject 898. The hose system is replaced after each working day or after 24 hours of operation. The subject hose 894 is replaced after each subject chance.
It is the object of this invention to provide a hose system, a squeeze valve and measuring interface, which simplify inserting and removing the hose system into or from a injector. This object is achieved by the subject matter of the independent claims.
Preferred embodiments of the invention are the subject matter of the dependent claims.
The advantage of a U-shaped pump hose is that it can be easily inserted into a roll pump. Hook-like, tunnel-like or wall-like sections are convenient for assembling the hoses onto the frame.
Fixing the contrast agent and saline solution piercing needle to the frame further simplifies inserting and removing of the hose system at the expense of a bigger frame.
A second frame, to which the contrast agent and saline solution piercing needles are fixed, advantageously reduces the size of a shipping package compared to a single big frame, to which the contrast agent and saline solution piercing needles are fixed. The solution with a second frame constitutes an advantageous trade-off between a small frame and many handling points and a big frame with few handling points.
Any frame may constitute part of the sterile shipping packaging of the hose system, thereby advantageously saving material for the packaging.
An ultrasonic flow measuring section advantageously provides a second, redundant means for flow measurement in addition to the roll pump. Consequently, error states may more reliably be detected.
An upper and lower panel which are glued or welded to each other allow a more automated assembling of the frame. To this end, the upper panel comprises guidances, which form part of the contrast agent or saline solution conduit.
An additional membrane fixed to the upper panel advantageously allows to integrate a number of functional units like de-aeration and squeeze valves, and interfaces like a pressure measurement interface into the frame without the need of manually fiddling around with hoses during assembling of the hose system.
A swelling in the membrane above or below a valve cavity renders the membrane more robust. A swelling which extends into the valve cavity arranges for a reliably tight closing of the squeeze valve at a moderate force applied by the plunger.
A pressure measuring interface integrated into the frame allows to re-use the expensive pressure sensors. It is noted that the frame with the hose system is to be replaced each day.
An abutment advantageously ensures a reliable pressure measurement by a pressure sensor outside the frame and the hose system.
The advantage of a first connection conduit, which connects an output of the saline solution valve with an output of the contrast agent valve and connecting the pump hose to the output of the contrast agent valve reduces dead space in the conduits. For the same purpose a second connection conduit may connect the output of the contrast agent valve with an output of a second contrast agent valve.
In the following preferred embodiments of this invention are described referring to the accompanying drawings.
While the present invention is described with reference to the embodiments as illustrated in the following detailed description as well as in the drawings, it should be understood that the following detailed description as well as the drawings are not intended to limit the present invention to the particular illustrative embodiments disclosed, but rather the described illustrative embodiments merely exemplify the various aspects of the present invention, the scope of which is defined by the appended claims.
The main difference of the inventive hose systems with respect to a conventional hose system shown in
The pump hose 132 delivers the fluid to an ultrasonic flow sensor 51 and further to a de-aeration area 22. The U-shaped arc of the pump hose 132 is inserted into a roll pump which is not shown in
The injector casing 1 has two handles 2 and 3.
Handling points are marked with a reference numeral 5. Handling points 5 are to be handled by an operator when inserting the hose system into the injector, more specifically the injector casing 1. There are only three handling points on frame 135. The price for the small number of handling points is a large number of frame mounting points designated by reference numerals 7 and hose mounting points designated by reference numeral 6. Frame mounting points 7 are points at which the hoses are fixed to the frame 135 when the hose system is assembled. Hose mounting points are points at which the hoses are fixed to something else than the frame 135, e.g. piercing needles 102. 112 and 122.
In total there are 9 handling points 5, 10 frame mounting points 7 and 11 hose mounting points 6.
The second embodiment has as few as 3 handling points 5 at the expense of 16 frame mounting points 7 and again 11 hose mounting points 6. Due to the few handling points 5 the inserting and removal of a hose system according to the second embodiment is actually even simpler than the inserting and removal of a hose system according to the first embodiment. Since the frame 235 is bigger than the frame 135, the packaging of the second embodiment of the first inventive hose system will require more space. Due to 16 frame mounting points 7, assembling of the second embodiment of the first inventive hose system is likely to be more expensive. Since the piercing needles 202, 212 and 222 are fixed to the frame 235, it is not possible to swivel down any of the containers 801, 811 and 821 by 135° for a drip-free changeover of the containers 801, 811 and 821.
It should be noted that the piercing needles 202, 212 and 222 have a vertical orientation, whereas the side of the injector casing onto which the frame 235 is mounted is inclined by approximately 40° to 50° with respect to the vertical direction. Consequently, the frame 235 cannot be substantially flat, rather the frame 235 has to be kinked. The upper and lower part of the frame 235 include an angle of 40° to 50°.
The second embodiment further comprises a left contrast agent hose 206, a saline solution hose 216, a right contrast agent hose 226, a pump hose 232, a pressure measurement chamber 262 and a particle filter 265.
The third embodiment further comprises a pump hose 332, a pressure measurement chamber 362 and a particle filter 365.
The hook-like, tunnel-like or wall-like sections 8 for fixing hoses 206, 216, 226, 232, 306, 316, 326 and 332 are not shown in
In order to provide a hose system, which is more suited for automated assembling, the inventors suggest to use a cartridge for the frames 135, 235 and 335.
The cartridge for the second hose system shown in
The upper panel 435 comprises guidances 401 and 403 which replace part of the left contrast agent hose. After the upper and lower panels 435 and 436 have been assembled, the guidances form part of conduits. In this document “conduits” is a generic expression which includes rigid tubes formed by the guidances and panels, and flexible hoses. The upper panel 435 further comprises guidances 411 and 413 which replace part of the saline solution hose. In addition, the upper panel 435 comprises guidances 421 and 423 for replacing part of the right contrast agent hose. The left contrast agent hose, the saline solution hose and the right contrast agent hose may be glued to pull relieves 404, 414 and 424, respectively, which are inlaid members in the embodiment shown in
Guidance 431 defined within upper panel 435 together with ultrasonic flow measuring section 451 and hose 460 replace part of the pump hose. An extra cross connector is not necessary. Hose 460 is fixed by hook-like, tunnel-like or wall-like sections 8, which protrude from the upper panel 435 to the lower panel 436.
The upper and lower panels 435 and 436 comprise cut-outs 402 and 403, which allow that hose piece 405 is squeezed off by a plunger, which is known in the art as explained above. Consequently, hose piece 405 operates like a stop valve. In a similar fashion cut-outs 412 and 416 together with hose piece 415 and cut-outs 422 and 426 together with hose piece 425 operate like two other stop valves. As mentioned above, during operation at least two hose pieces are squeezed off that only liquid through the un-squeezed hose piece is delivered to the subject. It is worth noting that the plungers for squeezing off the hose pieces 405, 415 and 425 are mounted in the injector casing 1. When the cartridge is inserted into the injector, the lower panel 436 is facing the injector casing. Consequently, in another embodiment, the cut-outs 402, 412 and 422 may be missing in the upper panel 435, rather the respective areas of the upper panel 435 may constitute an abutment, against which the plungers squeeze those pieces 405, 415 and 425.
The pump hose 432 is fixed by pull relieves 480 and 481. to the upper and lower panels 435 and 436. The pump hose 432 may he glued or welded to the pull relieves 480 and 481. Since the pump hose is kneaded and pulled by the roll pump and the roll pump generates a pressure of up to 20 bar, the pump hose 432 may be additionally fixed to the pull relieves 480 and 481 by hose clamps and the pull relieves 480 and 481 may be bigger than the pull relieves 404, 414 and 424. Due to the pressure of up to 20 bar, hoses 462 and 482 rather than guidances integrated into the upper and lower panels 435 and 436 are suggested for delivering the fluids from the subject-sided end of the pump hose 432. Another reason for this design is that hose 462 operates as pressure measurement chamber, which is mechanically connected to the pressure transducers (not shown in
Between hoses 462 and 482 the particle filter 465 is positioned. Since there may be a substantial pressure drop over the particle filter 465 and the pressure drop depends on the flow through the particle filter 465, the particle filter 465 has two small wings acting as pull relieves like other pull relieves 404, 414 and 424. Finally another pull relief 483 connects the short hose 482 to another hose, which is not shown in
For the ultrasonic flow measuring section 451 two cut-outs 450 and 453 are provided in the upper panel 435 and the lower panel 436, respectively. The cut-outs 450 and 453 are bigger than the ultrasonic flow measuring section 451, because the ultrasonic transducers must have access to the flat surfaces terminating the measuring distance. The ultrasonic transducers are not shown in
The cut-out 461 provides access to the hose 460 for de-aeration purposes. The cut-outs 472 and 471 provide access to the pump hose 432 for bubble detection by an ultrasonic detector. The hoses 460, 462 and 482 and the pump hose 432 may be fixed and guided by hook-like, tunnel-like or wall-like sections 8, which are fixed to the upper and/or lower panels 435 and 436. Such sections are also shown in
The first embodiment of the second hose system comprises 9 handling points, 5 frame mounting, points and 17 hose mounting points.
The second embodiment of the second hose system comprises 3 handling points, 11 frame mounting points and 17 hose mounting points.
The third embodiment of the second hose system comprises 5 handling points, 11 frame mounting points and 17 hose mounting points.
The handling points of the three embodiments of the second hose system are similar to the handling points of the respective embodiment of the first hose system. The number of hose mounting points is identical for the embodiments of a hose system.
Guidance 531 defined within upper panel 535 together with ultrasonic flow measuring section 551 and broad guidance 560 replace part of the pump hose. An extra cross connector as shown in
Valve cavities 502, 512 and 522 together with cut-outs 506, 516 and 526 and the respective membrane areas 507, 517 and 527 form three stop valves which will be explained in more detail in connection with
As in the embodiment shown in
The pump hose 532 is fixed by pull relief 580 and 581 to the upper and lower panels 535 and 536. The pump hose 532 may be glued or welded to the pull relieves 580 and 581. Again, the pump hose 532 may he additionally fixed to the pull relieves 580 and 581 by hose clamps and the pull relieves 580 and 581 may be bigger than the pull relieves 504, 514 and 524.
The broad guidance 560 together with a cut-out 561 and the respective membrane area 575 serve de-aeration purposes. The thickness of the membrane in the membrane area 575 may be increased. Actually, a cross-section through the broad guidance 560, the cut-out 561 and the membrane area of 575 may be similar to a cross-section through a squeeze valve. The difference to a squeeze valve is that a plunger beats the membrane area of 575 repeatedly in order to make the fluid before the broad guidance 560 move repeatedly backwards and forward. Thereby, bubbles move upward into the respective container. No attempt is made to completely close the broad guidance 560.
At the subject-sided end of the pump hose 532, the cut-outs 571, 572 and 573 provide access to the pump hose 532 for bubble detection by an ultrasonic detector. Hook-like, tunnel-like or wall-like sections 8 protruding from the lower panel 536 to the upper panel 535 guide the pump hose 532 so that the pump hose 532 is reliably inserted into the ultrasonic detector. Then a guidance 567 delivers the liquid to a filter tissue 565, which constitutes a particle filter. Another guidance 568, which is formed by the lower panel 536, collects the liquid after the filter tissue 565 and delivers the liquid to another pull relief 582, which connects to another hose, which is not shown in
When designing the gluing and/or welding areas between the upper panel 535 and the lower panel 536, it has to be borne in mind that the guidances 567 and 568 and the particle filter in between must stand pressures up to 20 bars. Consequently, the overlapping sections of guidances 567 and 568 and the filter tissue 565 should be long and narrow in order to keep the forces per length unit along the. overlapping sections small. This may also be achieved by a comb or rib-like structure for a short and broad filter tissue. Another possibility is to move the filter tissue to the low-pressure side before the pump hose 532. A third possibility is to design the injector casing of the injector so that the upper and lower panels 535 and 536 can lean to two parts of the injector casing. In other words: the two parts of the injector casing act as abutments to the force generated by a high pressure during operation.
The upper and lower panels 535 and 536 maybe glued to the two sides of the membrane 537. In addition or alternatively the membrane of 537 may comprise additional cuts-outs, which are not shown in
The guidance 567 together with recesses 563 and 564 and the respective swellings 577 and 578 of the membrane form two pressure interfaces equivalent to the measurement chamber. The pressure interfaces will be explained in more detail in connection with
The first embodiment of the third hose system comprises 9 handling points, 6 frame mounting points and 10 hose mounting points.
The second embodiment of the third hose system comprises 3 handling points, 11 frame mounting points and 14 hose mounting points.
The third embodiment of the third hose system comprises 5 handling points, 11 frame mounting points and 10 hose mounting points.
The handling points of the three embodiments of the third hose system are similar to the handling points of the respective embodiment of the first hose system. The reduced numbers of hose mounting points of the three embodiments of the third hose system compared to the respective one of three embodiments of the second hose system show that the assembling of the third hose system is automatable to a great. extent.
Although the pump hoses 132, 232, 332, 432, 532 have been described as U-shaped in connection with
Right of the swelling 607, the lower panel 536 has the cut-out 606 which is bigger than the valve cavity 602 and the swelling 607 viewed from a direction normal to the membrane 537.
The casing membrane 538 is fixed to the injector casing 1 to protect and in particular seal the plunger 685 and the interior of the injector casing against spilt over contrast agent and saline solution when the containers are changed and other detrimental influence.
The main purpose of this embodiment is to reduce the mixing of saline solution and contrast agent. A dilution of contrast agent by saline solution is less detrimental than the contamination of saline solution by contrast agent. In this regard, the embodiment shown in
The guidances 713, 703 and 731 connect the valve cavities 712, 702 and 722 in a cascade-like or meander-like manner. The result is that the saline solution. provided by guidance 711 flushes the guidances 713, 703 and 731. Dead spaces for contrast agents are minimized to dead spaces with the squeeze valves corresponding to the valve cavities 712, 702 and 722. In the previous embodiments, guidances 403 and 423 as well as 503 and 513 constitute dead spaces for contrast agents, when saline solution is flowing.
When the left contrast agent is flowing, the design shown in
Guidances 703 and 713 constitute dead space for the right contrast agent originating from guidance 721. If comparable design parameters like guidance width and distance of valves are used, the guidances 713 and 703 comprise more dead space than the guidances 503 and 513 or 403 and 413. However, guidance 713 is not critical, since the saline solution within swims on top of the contrast agent and the dead space within guidance 703 is smaller than the dead space than the guidances 503 and 513 or 403 and 413. In addition, if a mixing of different contrast agents must be avoided, the guidances 713 and 703 can be rinsed by saline solution.
Further modifications and variations of the present invention will be apparent to those skilled in the art in view of this description. Accordingly, this description is to be construed as illustrative only and is for the purpose of teaching those skilled in the art the general manner of carrying out the present invention. It is to be understood that the forms of the invention shown and described herein are to be taken as the presently preferred embodiments.
| Number | Date | Country | Kind |
|---|---|---|---|
| 07111567.9 | Jul 2007 | DE | national |
This application is a continuation of application Ser. No. 11/895,455 filed Aug. 24, 2007 under the same title and inventors which claimed priority from European Patent Application (EPO), No. 07111567.9 having a filing date of Jul. 2, 2007.
| Number | Date | Country | |
|---|---|---|---|
| Parent | 11895455 | Aug 2007 | US |
| Child | 12944963 | US |
