Abstract:
A connectorized ultrasound probe includes a distal section that is configured for insertion into a patient&#39;s body and a proximal section configured to interface the distal section with an ultrasound system. The distal section is easily attachable and detachable from the proximal section using at least one set of connectors. When connected, a user-operated actuator located on the proximal section controls the bending of the distal section, and the ultrasound system sends driving signals to and receives return signals from the ultrasound transducer via the proximal section. This arrangement is particularly advantageous for long term monitoring, because the disconnectability of the proximal section makes it possible to leave the distal section in place in the patient for longer periods of time without undue discomfort. In some preferred embodiments, the mechanical interface is made before the electrical interface when the distal section is connected to the proximal section.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application claims the benefit of U.S. Provisional Application 60/987,081, filed Nov. 11, 2007. This application is also a continuation-in-part of U.S. patent application Ser. No. 11/279,510, filed Apr. 12, 2006, which claims the benefit of U.S. Provisional Application 60/671,808, filed Apr. 15, 2005. Each of those applications is incorporated herein by reference. 
     
    
     BACKGROUND 
       [0002]    U.S. application Ser. No. 10/996,816, filed Nov. 24, 2004, which is incorporated herein by reference, describes a unique ultrasound probe, transducer, and associated algorithm. The probe disclosed in the &#39;816 application is significantly narrower than prior art devices, and can be left in place for extended periods of time. The primary intended use of that probe is for monitoring of the heart using echocardiography.  FIG. 1  is a schematic representation of that probe  100 . The probe has a flexible shaft  112  affixed to the end of an endoscope style control handle  104 , and the distal end  116  of the probe  100  contains the ultrasound transducer  118 . To use the probe, the distal end  116  is manipulated into position in the esophagus, and a bending mechanism is then actuated using actuator  102 , which causes the bending section  114  of the probe to bend. In the context of echocardiography, this bending action is used to position the ultrasound transducer  118  in the fundus of the stomach to obtain an image of the transgastric short axis view of the heart. The handle  104  is connected to a connector  42  on the ultrasound system  40  via a cable  106  that terminates at a connector  108 . 
         [0003]    In the setting of an intensive care unit (ICU), patients are often maintained in a quiescent state for both the well-being of the patient and to facilitate the monitoring of various physiological functions. Leaving the probe  100  in place for extended periods of time, however, can create difficulties in common situations when the patient must be moved. (Examples of such situations include moving the patient to clean him or her, to prevent pressure sores, or to perform routine procedures.) If the probe  100  is kept in the patient while the probe is hooked up to the ultrasound system  40 , moving the patient could be extremely difficult. 
         [0004]    One solution to this problem is to detach the probe  100  from the ultrasound system  40  by disconnecting the probe&#39;s connector  108  from the ultrasound system&#39;s connector  42  before the patient is moved, to leave those portions of the probe that remain outside the patient&#39;s body  102 - 108  resting on a tray or a hook. However, since the handle  104  and associated cable portions  106  of the transesophageal echo (TEE) probe that remain attached to the patient are relatively large and heavy, this solution is somewhat clumsy, and requires an extra degree of awareness from the attendants so as to not dislodge the device or cause other problems due to paying too much attention to the device. 
       SUMMARY 
       [0005]    A connectorized ultrasound probe includes a distal section that is configured for insertion into a patient&#39;s body and a proximal section configured to interface the distal section with an ultrasound system. The distal section is easily attachable and detachable from the proximal section using at least one set of connectors. When connected, a user-operated actuator located on the proximal section controls the bending of the distal section via the connectors, and the ultrasound system sends driving signals to and receives return signals from the ultrasound transducer via the proximal section. In some preferred embodiments, the mechanical interface is made before the electrical interface when the distal section is connected to the proximal section. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0006]      FIG. 1  is a schematic representation of the transesophageal echocardiography ultrasound probe disclosed in the &#39;816 application. 
           [0007]      FIG. 2  is a schematic representation of a first embodiment of an improved ultrasound probe for transesophageal echocardiography in accordance with the present invention. 
           [0008]      FIG. 3  is an isometric view of an implementation of the ultrasound probe of  FIG. 2 , with a transducer assembly connected to a matching actuator assembly. 
           [0009]      FIG. 4  is a first detailed view of the interface between the transducer assembly and the actuator assembly of the  FIG. 3  embodiment. 
           [0010]      FIG. 5  is a detailed view of the interface portion of the actuator assembly of the  FIG. 3  embodiment. 
           [0011]      FIG. 6  is a detailed view of the interface portion of the transducer assembly of the  FIG. 3  embodiment. 
           [0012]      FIG. 7  shows the internal components of the transducer assembly of  FIG. 6 , with the lid removed. 
           [0013]      FIG. 8  shows the transducer assembly of  FIG. 6 , with certain components removed to make the lower components visible. 
           [0014]      FIG. 9  shows the electrical and mechanical interactions between the transducer assembly and the actuator assembly when those two assemblies are mated together. 
           [0015]      FIG. 10  is another embodiment of an improved ultrasound probe for transesophageal echocardiography in accordance with the present invention. 
           [0016]      FIG. 11  is a detail of the mechanical connection on the actuator assembly side of the probe of  FIG. 10 . 
           [0017]      FIG. 12  is a detail of the mechanical connection on the transducer assembly side of the probe of  FIG. 10 . 
           [0018]      FIG. 13A  shows an alternative output actuator mated with an alternative control actuator, for use with the embodiments shown in  FIGS. 3-9 . 
           [0019]      FIG. 13B  is a detail of the alternative output actuator of  FIG. 13A . 
           [0020]      FIG. 13C  is a detail of the alternative control actuator of  FIG. 13A . 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0021]    The drawbacks associated with a large handle and cabling that remains connected to the patient while the probe is in the patient&#39;s esophagus can be avoided or minimized by using a connectorized probe, with a distal portion that remains installed in the patient, and a detachable handle portion that interfaces with the distal portion. The connector passes both mechanical and electrical signals between the two portions. Optionally, the distal portion may be disposable, in which case it is preferable to reduce the cost of the distal portion. Because it is not disposable, the cost of the handle portion is less critical. 
         [0022]      FIG. 2  is a schematic representation of an embodiment of the invention, with a probe that includes an actuator assembly  80  and a transducer assembly  60 . The actuator assembly  80  includes a control handle  84  with an actuator  82 . The handle  84  is connected to a connector  42  on the ultrasound system  40  via a cable  86  that terminates at a connector  88 . The transducer assembly  60  has a flexible shaft  62  affixed to the end of a connector  70 , and the distal end  66  of the probe contains the ultrasound transducer  68 . To use the probe, the actuator assembly  80  and the transducer assembly  60  are connected together by mating the first connector  90  with the second connector  70 . The distal end  68  is then manipulated into position in the esophagus. The transducer assembly  60  includes a bending mechanism that is actuatable by the actuator  82  when the actuator assembly  80  and the transducer assembly  60  are connected together. This causes the bending section  64  of the probe to bend to provide an end result that is similar to the bending achieved in the unitary probe described above in connection with  FIG. 1 . 
         [0023]    Now, when it becomes necessary to move the patient, the transducer assembly  60  is disconnected from the actuator assembly  80  at the connectors  70 ,  90 , so that the only parts that remain protruding from the patient will be the proximal end of the shaft  62  and the connector  70 . Since those portions are relatively small and light compared to the handle  104  and cable  106  of the probe  100  depicted in  FIG. 1 , it becomes much easier to leave the distal end of the probe in the patient when the patient has to be moved or cared for. 
         [0024]      FIG. 3  depicts a preferred implementation of the  FIG. 2  embodiment, with the transducer assembly  60  mounted to the actuator assembly  80 . The transducer assembly  60  include includes a flexible shaft  62  (shown with a break to denote its long length) that has a bending section  64 . The shaft  62  is preferably less than 6 mm in diameter, and preferably on the order of 1 m in length for an adult version of the device. Those dimensions may be scaled down appropriately for pediatric and neonatal patients. The distal end  66  of the transducer assembly  60  houses the ultrasound transducer which is preferably transversely oriented with respect to the proximal distal axis. In alternative embodiments, other transducer configurations may be used in place of the transversely oriented transducer (e.g., a two-dimensional ultrasound transducer or a rotating multi-plane transducer). The actuator assembly  80  includes a handle  84  with a user-operated actuator  82  mounted on the handle. A cable  86  with a connector  88  at its proximal end (both shown in  FIG. 2 ) extends from the proximal end of the handle  84 . This connector  88  mates with a corresponding connector  42  on the ultrasound system  40  (all shown in  FIG. 2 ). 
         [0025]      FIG. 4  is an exploded detail view of the interface between the actuator assembly  80  and the transducer assembly  60 . The actuator assembly  80  includes a first connector  90  that interfaces with the transducer assembly  60 , and the transducer assembly  60  includes a second connector  70  that interfaces with the actuator assembly  80 . The first connector  90  includes a first electrical interface  94 , which is used to make electrical connect with a mating connector (not shown) on the second connector  70 . In the illustrated embodiment, the first electrical interface  94  comprises a series of conductive pads, which are preferably gold plated. The pads may be flat or raised. Preferably, the first connector is constructed to be watertight so that the first connector can be immersed in a liquid sterilant (e.g., Cidex glutaraldehyde, peroxide sterilants, etc.), and using simple, stationary pads helps achieve the desired watertightness, which facilitates re-use of the actuator assembly  80  for multiple patients. When the second connector  70  is mated to the first connector  90 , corresponding contacts on the second connector  70  line up with the contacts of the first electrical interface  94  so that electrical signals can pass between the actuator assembly  80  and the transducer assembly  60 . 
         [0026]    The ultrasound system  40  communicates with the ultrasound transducer  68  (both shown in  FIG. 2 ) by sending and receiving appropriate signals into the actuator assembly  80  via the connector  42 , the connector  88 , and the cable  86  (all shown in  FIG. 2 ). The signals that travel through the cable  86  are routed to the first electrical interface  94  on the first connector  90  e.g., by running appropriately shielded wires from the distal end of the cable  86  directly to the first electrical interface  94 . Optionally, appropriate intervening circuitry (e.g., amplifiers, signal conditioners, etc.) may be interposed between the first electrical interface  94  and the cable  86 . The remainder of the path to the transducer is described below in connection with the transducer assembly  60 . 
         [0027]    The first connector  90  also includes an output actuator  92  that is designed to mate with a corresponding member on the second connector  70  when the second connector  70  is connected to the first connector  90 . The output actuator  92  is linked to the user-operated actuator  82  by an appropriate mechanism such that the output actuator moves in response to user actuation of the user-operated actuator  82 . The link between the user-operated actuator  82  and the output actuator  92  may be implemented using any of a variety of conventional techniques, including but not limited to gears, pull wires, servo motors, stepper motors, hydraulics, as well as numerous other techniques that will be apparent to persons skilled in the relevant arts. The output actuator  92  and the user-operated actuator  82  are preferably also made using a watertight construction (e.g., using O rings or other sealing techniques) to facilitate liquid sterilization of the actuator assembly  80 . 
         [0028]      FIG. 5  shows the first connector  90  in even greater detail. As explained above, the output actuator  92  rotates in response to actuations of the user-operated actuator  82 . The surface of the output actuator  92  is preferably made of a material that will have a high coefficient of friction when it is pressed against a corresponding member in the second connector  70 . Examples of suitable materials for the output actuator include rubber, polyethylene, polystyrene, vinyl, etc. Optionally, a plurality of radial grooves may be cut into the surface of the output actuator  92  to help the output actuator  92  better “grab” the corresponding surface on the second connector  70 . 
         [0029]    As best seen in this view, the first connector  90  includes a number of mounting members for latching the first connector onto the second connector. Although the illustrated embodiment depict mounting members in the form of a pair of small tabs  97  at the distal end and a larger tab  96 , persons skilled in relevant arts will recognize that any of a wide variety of conventional latching mechanism may be used. 
         [0030]      FIG. 6  is a front view of the second connector  70 . The second connector  70  is configured to mate with the first connector  90 . To do this, the second connector  70  contains a second electrical interface  74  that lines up the first electrical interface  94  of the first connector  90 . In the illustrated embodiment, the second electrical interface  74  is made using a plurality of spring loaded fingers positioned so that, when the second connector  70  is connected to the first connector  90 , the fingers of the second electrical interface  74  will line up with the pads of the first electrical interface  94  (shown in  FIGS. 4 ,  5 ). The second connector  70  also contains a control actuator  72  that lines up the output actuator  92  of the first connector  90 , so that the output actuator  92  can drive the control actuator  72 . In the illustrated embodiment, the control actuator  72  is a rotating wheel that is designed to be driven by rotation of the output actuator  92 . Of course, a wide variety of alternative arrangements for actuating alternative control actuators will be readily apparent to persons skilled in the relevant arts. Note that when the transducer assembly  60  is disposable and will be discarded after each use, it is not necessary to make the second connector  70  watertight. 
         [0031]    To connect the first and second connectors, the second connector  70  is attached to the first connector  90  by aligning the notches  77  of the second connector  70  with tabs  97  of the first connector  90 , then squeezing the proximal end of second connector  70  towards the first connector  90 . The latching arm  76  on the second connector  70  is designed to snap into position on the first connector by interacting with tab  96  (shown in  FIG. 5 ). When the first connector  70  is attached to the first connector  90  in this manner, the second electrical interface  74  of the second connector  70  makes electrical contact with the first electrical interface  94  of the first connector  90 , so that electrical signals can travel back and forth between the first electrical interface  94  and the second electrical interface  74 . In addition, the control actuator  72  makes mechanical contact with the output actuator  92  of the first connector  90 , so that when the output actuator  92  is rotated in response to operation of the user operated actuator  82  (shown in  FIG. 4 ) the control actuator  72  will be driven by the output actuator  92  and follow the rotation of the output actuator  92 . A lid  79  protects the internal components of the second connector  70  from damage, and has cutouts to provide access to the second electrical interface  74  and the control actuator  72 . Note that while  FIGS. 4-9  depict first and second electrical interfaces  94 ,  74  using pads and fingers designed to contact the pads, numerous alternative electrical interfaces (e.g., pins and mating sockets) may be substituted therefor, as will be appreciated by persons skilled in the relevant arts. 
         [0032]      FIG. 7  is another view of the second connector  70  shown in  FIG. 6 , with the lid  79  removed. This view reveals that the rotating control actuator  72  is attached to a pulley  73  that causes the pull wires  65  to move when the control actuator  72  is rotated. This view also shows a portion of the ribbon cable  61 , which is the wiring that connects the second electrical interface  74  to the transducer  68  (shown in  FIG. 2 ) at the distal end  66  of the transducer assembly  60 . Preferably, a ground plane is provided on both sides of the ribbon cable. In less preferred embodiments one or both of those ground planes may be omitted, or wiring configurations other than ribbon cable may be used. Optionally, appropriate intervening circuitry (e.g., amplifiers, signal conditioners, etc.) may be interposed between the second electrical interface  74  and the transducer  68 . 
         [0033]      FIG. 8  shows yet another view of the second connector  70  of  FIGS. 6 and 7 , but with the lid  79 , the second electrical interface  74 , the wiring  61 , the control actuator  72 , and the pulley&#39;s axle all removed to show the lower components of the second connector  70 . This view more clearly shows how the pulley  73  moves the pull wires  65 , which extend out distally through the shaft  62 . When the pull wires  65  move (in response to rotation of the pulley), the pull wires operate the bending section  64  (shown in  FIG. 3 ) in any conventional manner. Since the pull wires  65  cause the bending section  64  to bend, and the pull wires  65  are moved by rotation of the pulley  73 , and rotation of the pulley  73  occurs in response to rotation of the control actuator  72  (shown in  FIGS. 6 and 7 ), the net result is that rotation of the control actuator  72  causes the bending section  64  to bend. 
         [0034]      FIG. 9  shows the electrical and mechanical interactions between the first connector  90  and the second connector  70  when those connectors are mated together. This view depicts the mated set of connectors  90 ,  70  would look if the outside housing of the second connector  70  were invisible. The second electrical interface  74  is lined up with and urged against the first electrical interface  94 , and the control actuator  72  on the second connector  70  is lined up with and urged against the output actuator  92  on the first connector  90 . A pulley mount  75  permits the pulley  73  to rotate and urges the control actuator  72  against the output actuator  92  when the first connector  90  and second connector  70  are mated. The ribbon cable  61  that connects the second electrical interface  74  to the transducer  68  (shown in  FIG. 2 ) at the distal end  66  of the transducer assembly  60  is also more clearly visible in this view. 
         [0035]    When the second connector  70  is mated with the first connector  90 , actuation of the user operated actuator  82  (shown in  FIGS. 3 and 4 ) will cause the output actuator  92  to rotate. Since the control actuator  72  is being urged up against the output actuator  92 , the control actuator  72  will follow the rotation of the output actuator  92 . Rotation of the control actuator  72  turns the pulley  73  which operates the pull wires  65  that extend distally through the flexible shaft  62 , and cause a bending mechanism (not shown) located in the bending section (shown in  FIG. 3 ) to bend. Thus, when the second connector  70  is mated to the first connector  90 , actuation of the user operated actuator  82  by the user will have the same net effect of actuations of the user operated actuator  102  of the unitary probe  100  depicted in  FIG. 1 . Note that while  FIGS. 4-9  depict using rotating pads for the output actuator  92  and the control actuator  72  pads, numerous alternative mechanical interfaces (e.g., gears, a hexagonal shaft and a mating socket, etc.) may be substituted therefore, as will be appreciated by persons skilled in the relevant arts. 
         [0036]    In addition, when the second connector  70  is mated with the first connector  90 , the second electrical interface  74  makes contact with the first electrical connector  94 . Since the first electrical connector  94  communicates with the ultrasound system  40  via cable  86  and connectors  88 ,  42  (all shown in  FIG. 2 ), and Since the wiring  61  connects the second electrical interface  74  to the transducer  68  at the distal end  66  of the transducer assembly  60  (shown in  FIGS. 2 ,  3 ) this arrangement permits the ultrasound system  40  to interface with the transducer  68  in the same way that the ultrasound system  40  communicates with the transducer  118  in the unitary probe  100  depicted in  FIG. 1 . Optionally, additional signals may be passed to and from the transducer assembly  60  via the first and second connectors  90 ,  70 , e.g., to operate a thermistor located in the distal end of the transducer assembly  60  or to interface with a non-volatile memory device located in the transducer assembly  60  (used, e.g., to store data relating to the transducer assembly  60 ). 
         [0037]    As best seen in  FIGS. 4 and 9 , the electrical and mechanical interface between the transducer assembly  60  and the actuator assembly  80  is sideways-facing (i.e., the mating surfaces of the first and second connectors  90 ,  70  face in a direction that is roughly perpendicular to the proximal-distal axis). This arrangement stands in contrast to the situation where one mating surface faces distally, and the other mating surface faces proximally (like the interface between the connectors  12 ,  22  in the  FIG. 10  embodiment described below). Using a sideways-facing interface advantageously provides a large amount of “real estate” (i.e., area) for implementing the electrical and mechanical connections between the two assemblies. Moreover, despite the fact that a large amount of real estate is available for the interface, the overall diameter of the assemblies  60 ,  80  when connected can remain small (e.g., about 22 mm, measured at the proximal end of second connector  70  in the embodiment illustrated in  FIGS. 3-9 ), and does not have to increase in proportion to the number of connections that are made between the first and second connectors  90 ,  70 . 
         [0038]      FIGS. 13A-C  show details of an alternative output actuator  192  that is designed to mate with an alternative control actuator  172 , for use in place of the output actuator  92  and control actuator  72  discussed above in connection with the embodiments shown in  FIGS. 3-9 . The operation of the output actuator  192  and control actuator  172  is similar to the operation of the output actuator  92  and control actuator  72 , except instead of relying on friction to transmit rotation between the face of the output actuator  92  and the face of the control actuator  72 , the output actuator  192  and control actuator  172  rely on a mating mechanical interface that is designed to transmit rotation. In the illustrated embodiment, this mating mechanical interface comprises a slot  193  in output actuator  192 , and a matching tab  173  in the control actuator  172 , however persons skilled in the relevant arts will appreciate that numerous other mating configurations can be substituted therefor. 
         [0039]    With this arrangement, the rotating mechanical components  172 ,  192  start to mate before the first connector  90  and the second connector  70  are “clicked” together, and electrical connection between the first electrical interface  94  and the second electrical interface  74  (shown in  FIGS. 5 and 6 , respectively) is not made until a bit later, when the first connector  90  and the second connector  70  are “clicked” together. This arrangement provides better tactile feedback to the user for both the mechanical and electrical connections than in embodiments in which those two connections are made at the same time. 
         [0040]    Preferably, the outer edges of the slot  193  are chamfered to help guide the tab  173  into position. Note that if the tab  173  does not line up with the slot  193  when the user initially attempts to mate the first connector  90  to the second connector  70 , the user can actuate the thumb actuator  82  (show in  FIG. 4 ) until the slot  193  in the output actuator  192  rotates to a position that aligns with the tab  173 , and then subsequently click the two connectors  70 ,  90  together. Since the two sections will only fit together when the slot  193  is aligned with the tab  173 , this arrangement forces a predetermined relationship between the thumb actuator  82  actuator and the bending section  64 . For example, leaving the thumb actuator  82  in the middle results in no bending; pushing the thumb actuator  82  causes the bending section  64  to retroflex; and pulling back on the thumb actuator  82  causes the bending section  64  to anteflex. 
         [0041]      FIG. 10  is another embodiment of the invention in which the insertion tube and acoustic block assembly (referred to above as the transducer assembly) are separable from the control handle (referred to above as the actuator assembly). In this embodiment, a durable handle  10  is connected to the transducer assembly  20 . A connector  12  at the distal end of the handle  10  mates with a corresponding connector  22  at the proximal end of the transducer assembly  20 .  FIG. 11  shows a detail of the latching arm  15  of the handle portion  10 , and  FIG. 12  shows a detail of the connector portion  22  of the transducer assembly  20 . 
         [0042]    Referring now to  FIGS. 10-12 , the connectors  12 ,  22  provide a detachable electrical interface to get all the necessary electrical signal to the distal end of the probe, and to receive return signals from the distal end of the probe. For example, the electrical connections may be used to pass signals used for generation of ultrasound at the ultrasound transducer  24 , return of electrical signals from the transducer, ground and shielding planes, and any other electrical functions that are implemented at the distal end (e.g., connections to a non-volatile memory device may be integrated into the transducer assembly). 
         [0043]    The connector  22  and the arm  15  also provide a detachable mechanical interface to actuate controllable portions at or near the distal end of the probe. An example of a desirable mechanical motion is flexing of the tip of the probe, which may be useful after the probe has been positioned in the fundus of the stomach. In the illustrated embodiment, the mechanical interface is implemented using pull wires that are connected to the distal end of the probe, where they initiate the desired motion (e.g., flexing of the probe tip). The mechanism that responds to the pull wires at the distal end of the probe may be implemented in any conventional manner. At the proximal end of the transducer assembly  20 , the pull wires terminate in sliders  28  with a female hole. 
         [0044]    To use the probe, the connector  22  is mated with the corresponding connector  12  of the handle, and the latching arm  15  is moved into position so that its pins  18  are mated into the sliders  28  of the transducer assembly  20 . The latching arm may include a catch  16  to hold the transducer assembly  20  to the handle portion  10 . The slides  18  are connected to each other via flexible cabling  17  which traverses a pulley  19  at the distal end of the latching arm  15 . This configuration helps insure that articulation control cable stays taut within the handle and does not require the use of springs to take up slack. 
         [0045]    The handle  10  includes a control surface  18  which may be implemented in any conventional way e.g., using pull wires. However, instead of having the pull wires go directly to the distal end of the probe, the pull wires the handle move the sliders  18  in the arm  15 . Those sliders  18  in turn move the sliders  28 , which move the pull wires  27  that run through the lumen of the transducer assembly  20  to generate the desired motion at the distal end of the probe. The result is a distal articulation mechanism that passes through a connector. 
         [0046]    One suitable way to implement the electrical connection between the connectors  12 ,  22  is to use a flexible printed circuit board (PCB) similar to the type used in ink jet cartridge connectors. The reverse side of this flexible PCB has traces which are pulled out and connected to the appropriate cabling. Optionally, a chip with non-volatile memory may also be mounted on the flexible PCB. A suitable mating connector for this interface is a “pogo pin” type interface with pins mounted in a block (not shown), as commonly used in electronic testing apparatus. 
         [0047]    Optionally, the actuator assembly in any of the embodiments described above may incorporate other actuatable features in addition to the basic articulation controls for manipulating the distal end of the insertion tube and transducer. For example, other mechanical connections besides the bending controls discussed above may be implemented, e.g., to transfer torque to the distal end of the probe. Controls for non-mechanical features may also be implemented on the handle, e.g., buttons for freezing the image, adjusting gain control or other functions. Optionally, the mechanical and electrical connections may be configured to be water-tight. 
         [0048]    In all the above-described embodiments, when the transducer assembly is connected to the actuator assembly via the connector or connectors, the combination of the transducer assembly with the actuator assembly emulates both the electrical and mechanical operation of a conventional ultrasound probe. However, with the embodiments described above in connection with  FIGS. 2-12 , the doctor gains the ability to disconnect the actuator assembly from the transducer assembly, and leave the relatively compact distal transducer assembly section in position in the patient&#39;s esophagus. When this is done, only the connector  70 ,  22  and a portion of the flexible shaft  62 ,  20  will remain attached to the patient&#39;s body, and the handle, the actuator, and the cable that links the handle to the ultrasound system are disconnected from the patient. Since the hardware that stays attached to the patient&#39;s is smaller and lighter, it becomes much easier to move the patient around and to attend to the patient&#39;s needs, and is much less cumbersome as compared to the  FIG. 1  embodiment in which the handle  104  and cable  106  stay attached to the patient as long as the transducer remains in position in the patient&#39;s esophagus. Preferably, the transducer assembly is configured so that the portion of the transducer assembly that remains outside of the patient&#39;s body is compact and has a mass of 250 g or less and a length of 70 cm or less. 
         [0049]    Reducing the amount of hardware that is attached to the patient&#39;s is particularly advantageous for long term transesophageal ultrasound imaging, e.g., in situations where the probe remains installed in the patient for hours or days at a time. These advantages become even more important if the patient is awake or is not anesthetized, in which patient comfort becomes an even more important factor. 
         [0050]    Advantages of the above-described embodiments include the fact that the device can be placed and left in-situ without causing problems with excessive bulk or cabling. In addition, by making the handle/actuator assembly separable from the transducer assembly, the transducer assembly may be made disposable and the handle may be made durable and reusable. This allows a less expensive disposable than would be possible if the entire probe were made disposable. It also allows the handle to be made to a higher standard than possible if the handle was also disposable, which may improve the tactile feedback to the user and ease of use. 
         [0051]    While the above-described embodiments are discussed in the context of transesophageal echocardiography, similar probes may be used to obtain other transesophageal images as well as to obtain ultrasound images in cavities other than the esophagus. The connectorized construction may also be incorporated into probes, endoscopes, or catheters in non-ultrasound medical applications, and may even be used in non-medical uses where it is desirable to disconnect a proximal section while leaving the distal section in place. Numerous other modifications to the above-described embodiments will be apparent to persons skilled in the relevant arts, and are also included within the purview of the invention.