Patent Abstract:
A medical ultrasonic probe includes an ultrasonic probe having a probe head and a connector. The connector includes a fluid cooling system comprising a pump configured to pump a cooling fluid between the connector and the probe head. A damper including a housing has a first portion defining a cavity receiving the cooling fluid and a second portion including a gas that is separated from the first portion by a membrane.

Full Description:
BACKGROUND 
       [0001]    Medical ultrasonic probes may host a plurality of electronics in the probe handle. Thermal management may become a challenge in the presence of electronics with considerable power consumption in the probe handle. In some cases, the heat generated by this power consumption is not sufficiently removed by means of natural convection via the probe surface. In such cases an additional cooling system such as the liquid cooling systems taught in U.S. Pat. No. 8,475,375, incorporated herein by reference in its entirety, may be employed. 
       SUMMARY 
       [0002]    In one embodiment a medical ultrasonic probe includes an ultrasonic probe having a probe head and a connector. The connector includes a fluid cooling system comprising a pump configured to pump a cooling fluid between the connector and the probe head. A damper including a housing has a first portion defining a cavity receiving the cooling fluid and a second portion including a gas that is separated from the first portion by a membrane. 
         [0003]    In another embodiment a vibration damper for an ultrasonic probe includes a damper located within a connector of a portable medical ultrasonic probe. The damper forms an interior chamber. An elastomeric membrane is mounted in the chamber separating the chamber into a first compartment having a sealed air compartment and a second compartment having a fluid inlet port and a fluid outlet port for respectively receiving and releasing a cooling fluid. 
         [0004]    In another embodiment a process for providing fluid cooling to medical ultrasonic probe includes providing a medical ultrasonic probe having a probe head with a first heat exchanger. The process further includes providing a connector containing a cooling system connected to the medical ultrasonic probe by fluid lines and comprising second heat exchanger; a pump; and a damper which absorbs vibrations induced in a cooling fluid within by the operation of the pump. The process also includes operating the pump to drive the cooling fluid through the damper, the first heat exchanger and the second heat exchanger through the fluid lines. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0005]      FIG. 1  is a schematic representation of an ultrasound robe and connector. 
           [0006]      FIG. 2  is representative view of fluid flow within a damper. 
           [0007]      FIG. 3  is a cross-sectional view of the damper. 
           [0008]      FIG. 4  is an exploded view of the damper. 
           [0009]      FIG. 5  is a view of an ultrasound probe including a probe head, cable and connector. 
           [0010]      FIG. 6  is a schematic representation of an ultrasound probe and connector with an alternative fluid flow circuit. 
       
    
    
     DETAILED DESCRIPTION 
       [0011]    Referring to  FIG. 1  and  FIG. 5 , an ultrasound probe  10  includes a probe head  12 , a connector  14  and a cable  16  connecting the probe head  12  to the connector  14 . Probe head  12  includes a transducer and receiver to send and receive ultrasound energy. Cable  16  provides for electric and fluid communication between the probe head  12  and connector  14 . Connector  14  includes an interface  18  to an ultrasound station that may include a monitor and processor for processing the images received from the probe head and sending instructions for operation of the probe head. 
         [0012]    Referring to  FIG. 1 , a cooling system allow for heat created from the ultrasound probe electronics to be removed from the probe. The cooling system includes a first heat exchanger  20  located within probe head  12 , a second heat exchanger  22  located within the housing  24 . The first heat exchanger  20  is in fluid communication with the second heat exchanger  22  with a conduit portion  26  that extends through cable  16 . A cooling fluid is pumped through the conduit portion  26  to transfer heat from the first heat exchanger  20  to the second heat exchanger  24 . In one embodiment the cooling fluid is a liquid. A fan (not shown) located within the housing of connector  14  circulates air over the second heat exchanger  22  to remove heat that is transferred from the first heat exchanger  20  to the second heat exchanger  22 . In one embodiment second heat exchanger  22  has a number of external ridges or fins to increase the outer surface area of the second heat exchanger  22  to assist in removing heat from the second heat exchanger  22 . 
         [0013]    In one embodiment, connector  14  includes a reservoir  28  in which a pump  30  is located. Pump  30  is the device that circulates the cooling fluid between the first heat exchanger  20  and the second heat exchanger  24 . Second heat exchanger  22  is in fluid communication with reservoir  28  and pump  30  through a conduit portion  32 . Pump  30  may cause pressure variations and resultant vibrations in the cooling fluid, as the cooling fluid is circulated between the first heat exchanger  20  and the second heat exchanger  22 . In one embodiment, pump  30  also causes the cooling fluid to flow to the first heat exchanger  20  after passing through a damper  34 . The cooling fluid is pumped from pump  30  to damper  34  through a conduit  36 . The cooling fluid after leaving damper  34  is directed to the first heat exchanger  20  via a conduit  38 . Conduit  26 ,  32 ,  36  and  38  may be tubes having a hollow portion through which the cooling fluid may circulate. Additionally, other fluid circuits are contemplated. Referring to  FIG. 6  the cooling fluid may be directed from the first heat exchanger  20  to the reservoir  28  and/or pump  30  via return conduit  26  and then from the reservoir/pump to the second heat exchanger  22  via a conduit  76  after which the cooling fluid may be circulated to damper  34  via a conduit  78  prior to being returned to the first heat exchanger  20 . 
         [0014]    In one embodiment, heat exchanger  22 , reservoir  28 , pump  30  and damper  34  are all located within a housing  40  of connector  14 . Damper  34  dampens, suppresses and/or ameliorates the transient and harmonic vibrations that are caused by the cooling fluid induced by pump  30  within the probe head  12 . In one embodiment damper  40  is to be understood as a separate element rather than a portion of the conduit or fluid tubes such as a compliant section of a fluid tube on the high-pressure side of the pump. Damper  40  is also to be understood as a deliberate added structure as opposed to the fluid air boundary in a partially filled reservoir. Damper  40  may be secured to or adjacent to an outer surface of reservoir  28  or maybe constructed as part of housing  40 . 
         [0015]    Referring to  FIG. 2 , damper  40  includes an inlet port  42  and an outlet port  44 . Inlet port  42  is operatively connected to conduit  36  to allow the cooling fluid from the pump to enter into damper  40 . Outlet port  44  is operatively connected to conduit  38  that in turn is connected to first heat exchanger  20 . In one embodiment damper  40  is located between the pump and/or reservoir and the probe head  12 . This placement reduces and/or eliminates the vibrations within the cooling fluid prior to entering the probe head. It is possible for damper  40  to be placed elsewhere in the cooling fluid flow circuit, such as between the pump and reservoir and or between the second heat exchanger and the pump or between the first heat exchanger and the second heat exchanger. 
         [0016]    Referring to  FIG. 2 , the cooling fluid entering inlet port  42  has a laminar flow. As the cooling fluid circulates within the damper  40  the flow of the cooling fluid is turbulent as represented by the non laminar flow lines  48 . The cooling fluid exits damper  40  through second inlet  44  with a laminar flow as the cooling fluid enters conduit  38  and is circulated to first heat exchanger  20 . 
         [0017]    Referring to  FIG. 3  and  FIG. 4 , damper  40  has a membrane  50 , a lower portion  52  and an upper portion  54 . The lower portion  52  is provided with inlet port  42  and outlet port  44  that are used for the inlet and outlet of the cooling fluid. The lower portion  52  and the upper portion  54  have mating threads  56  and  58  respectively that engage each other to securely assemble damper  40 . The lower member  52  is provided with a ledge  60  that supports the outer circumferential periphery of the membrane  50 . When the threads  56  and  58  are fully engaged the peripheral edge of membrane  50  is captured between the ledge  60  and a bottom edge  62  of the upper portion  54  in such a way that a fluid tight hermetic seal is obtained. Cooling fluid introduced into the damper  40  via input port  42  is kept in a cavity  64  formed by the lower portion  52  and the membrane  50 . 
         [0018]    Membrane  50  may be formed of an elastomeric material such that when it is stretched by pressure variations in the cooling fluid it absorbs energy. The energy of displacing the membrane  50  upward vibrations within the cooling fluid is at least partially dissipated in internal friction inherent in its displacement. In one embodiment the membrane is a fluoropolymer rubber. In one embodiment the membrane is an elastomer with a Shore A hardness of about 75. In one embodiment the membrane has a thickness of about 1 mm. Of course other Shore A hardness values and membrane thicknesses are contemplated. 
         [0019]    In one embodiment the upper portion  54  includes male threads that are threaded into the female threads  60  of lower portion  52 . Membrane  50  being captured the upper portion  54  and lower portion  52  until significant resistance is met to create a fluid tight seal. In this manner the cooling fluid within cavity  64  does not migrate into the gas cavity  66  between the membrane  50  and upper portion  54 . 
         [0020]    In one embodiment the lower portion  52  may be formed of a metal such as aluminum. Of course other types of materials are contemplated. Lower portion includes openings through which fluid inlet port  42  and fluid outlet port  44  extend. In one embodiment ledge  60  of lower portion  52  has a width of about 2.5 cm. Cavity  64  is configured such that the cooling fluid has a laminar flow entering inlet port  42  and is converted to turbulent flow as the cooling fluid circulates within the cavity  64  and then is converted back to laminar flow as the cooling fluid exits outlet port  44  through conduit  38 . In one embodiment cavity  64  has a cylindrical shape about 20 mm in diameter and about 2.7 mm in height. Of course other diameter and height dimensions are contemplated. 
         [0021]    Inlet port  42  and outlet port  44  each have a longitudinal axis that extends through a center portion of inlet port  42  and outlet port  44  respectively. In one embodiment, the longitudinal axis of inlet port  42  is not collinear with the longitudinal axis of outlet port  44 . In one embodiment the longitudinal axis of inlet port intersects the longitudinal axis of the outlet port within cavity  64 . The arrangement of inlet port  42 , outlet port  44  and the geometry of damper  40  contribute to the turbulent flow of the cooing fluid within cavity  64 . In one embodiment inlet port  42  and outlet port  44  are closely adjacent and extend from the arcuate outer circumference of the lower portion  52 . In one embodiment the longitudinal axis of the inlet port and the longitudinal axis of the outlet port form an angle of about 20 degrees. 
         [0022]    The gas within cavity  66  may be air or may be another gas to assist in the removal and minimization of vibrations within the cooling fluid as the cooling fluid is circulated to the probe head  12 . Membrane  50  maybe substantially planar in a neutral position or may have an arcuate shape as illustrated in  FIG. 3 . The shape of membrane  50  may vary depending on the pressure within the cooling fluid circuit and/or the vibrations within the cooling fluid as the cooling fluid enters damper  40 . 
         [0023]    Lower portion  52  includes an outer arcuate side wall through which the inlet port  42  and outlet port  44  extend and a base floor. Ledge  60  is generally parallel to the plane defined by the base floor. Cavity  64  is defined by the inner surface of the side wall  68  and the inner surface of the base floor  70  as well as the lower or first surface of membrane  50 . Similarly, cavity  66  is formed by the inner side wall  72  and the inner side of a cover portion  74  of upper portion  54  and the upper surface or second surface of membrane  50 . In one embodiment cavity  66  simply contains the ambient air present when the lower portion  52  and the upper portion  54  are threaded together. In one embodiment cavity  66  is about 3.2 mm high and has a diameter if about 20 mm over most of its height. In one embodiment the upper portion  54  is constructed of a metal such as aluminum. However, other materials are also contemplated. 
         [0024]    In one embodiment the longitudinal axis of inlet port  42  and outlet port  44  both lie in a common plane that is parallel to a plane defined by the ledge  60  and or base  70 . 
         [0025]    In one embodiment the damper is used in conjunction with a Doppler scan used to sense the movement of elements of a human body, such as flowing blood. The damper reduces the probability of artifacts caused by vibrations of the sensing head of probe head  12 . In the case of sensing blood flow this reduces or eliminates the possibility of the scan incorrectly indicating reverse blood flow. In one embodiment damper  34  is used with pumps that have a vibrational frequency of around 50 Hz and dominant higher harmonics up to 200 Hz and scans sensing frequencies of greater than 50 Hz. 
         [0026]    Although the present disclosure has been described with reference to example embodiments, workers skilled in the art will recognize that changes may be made in form and detail without departing from the spirit and scope of the claimed subject matter. For example, although different example embodiments may have been described as including one or more features providing one or more benefits, it is contemplated that the described features may be interchanged with one another or alternatively be combined with one another in the described example embodiments or in other alternative embodiments. Because the technology of the present disclosure is relatively complex, not all changes in the technology are foreseeable. The present disclosure described with reference to the example embodiments and set forth in the following claims is manifestly intended to be as broad as possible. For example, unless specifically otherwise noted, the claims reciting a single particular element also encompass a plurality of such particular elements.

Technology Classification (CPC): 6