Abstract:
An ultrasonic probe is provided. The probe includes a base member and an ultrasonic transducer housed by the base member. The probe also includes an intermediary damping member secured to the base member. The damping member includes an interior cavity for receiving an acoustic coupling fluid. The probe may optionally be secured to a flexible intermediary buffer. In an alternative embodiment, a coupling member is secured to the base member. The coupling member includes an interior cavity for receiving an acoustic coupling fluid. The coupling member also includes a malleable contacting surface for contacting an anatomical structure during use. Another alternative embodiment of the invention includes a transducer housing, an ultrasonic transducer mounted in the housing, and a flexible cushioned pad directly secured to a periphery of the transducer housing. Yet another alternative embodiment includes a pliable damping member defining an interior for retaining a fluid and structure for secured the damping member to an ultrasonic probe.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation-in-part of Application No. 09/223,403, filed Dec. 30, 1998 and issued as U.S. Pat. No. 6,139,502 on Oct. 31, 2000. 
    
    
     BACKGROUND OF THE INVENTION 
     The present invention generally relates to ultrasound probes and in particular to ultrasound probe and handle housings and cushions for use with ultrasound probes. 
     Ultrasonic diagnostic imaging probes generally have been used in the past to image anatomical structures within the body. Ultrasonic probes have been used in the past during non-invasive procedures (such as trans-thoracic probes), during invasive procedures (such as trans-esophageal echocardiography (TEE) probes and trans-vaginal probes), and during surgical procedures (i.e., intraoperative probes). 
     When using ultrasonic probes, it is important that the hand of the physician using the probe not obscure the site being examined. While the probe is imaging, for example, a physician must be able to accurately determine and maintain the position of the probe while looking at a monitor displaying the information obtained from the probe. 
     Past intraoperative ultrasound probes have provided, for example in U.S. Pat. No. 5,381,795 to Nordgren et al., an intraoperative ultrasound probe having a transducer section and an angled handle section that form an obtuse angle with respect to one another. The shape of the handle was used in an attempt to permit the physician to grasp the probe without blocking the physician&#39;s view of the surgical site. Surgical procedures in which intraoperative probes have been used include vascular surgery and transplant surgery. During vascular surgery, ultrasonic imaging probes can be used to image and diagnose the interior of carotid arteries. In transplant surgery, intraoperative ultrasonic probes can be used to verify successful attachment and function of renal arteries. Intraoperative ultrasound probes are preferably small and as easy to manipulate as surgical instruments. 
     Past trans-vaginal probes have provided, for example in U.S. Pat. No. 4,742,829 to Law et al., a handle offset from the central axis of the probe. The shape of the handle was used in an attempt to free the space around the entrance of a needle guide to thereby permit manipulation of the needle by hand. The probes disclosed in the above-referenced patents did not, however, present a probe having a multiple-angled handle section. 
     Past TEE probes have provided, for example in U.S. Pat. No. 5,351,691 to Brommersma, a flexible tube having at one end a probe head. The flexible end part is connected to a housing to allow a probe head to be bent forwards or backwards. 
     Several problems exist with respect to past ultrasound probes. During examination of organs within the body, particularly during intraoperative examination, the quality of ultrasound images is adversely affected by the presence of a moving organ, due to, for example, blood pulsation. For example, an ultrasound probe may be placed directly on a heart during open heart surgery. The pulsation of the heart applies forces to the ultrasound probe which cause the probe to move up and down and/or side to side and therefore adversely affect the quality of the ultrasound images obtained. The images may be adversely affected because returning ultrasound waves may miss the probe altogether (thereby producing no image) or return when the probe is at a different angle or orientation than when the ultrasound wave was sent (thereby causing an incorrect image to be produced). 
     Second, ultrasound images are adversely affected by the lack of an effective acoustic coupling due to the fixed (usually flat) transducer or probe surface and the curved or irregular shape of an anatomic structure, such as a heart, artery or other organ (especially during intraoperative examination). When a flat probe is placed against the curved or irregular surface of an anatomic structure, only a portion of the probe actually contacts the anatomic structure. When this occurs, air is located between the non-contacting portion of the probe surface and the anatomic structure. Ultrasonic waves travel at different speeds in air than in the anatomic structure. Because of the different speeds at which ultrasonic waves travel, the ultrasonic waves refract (i.e., bend sharply) when they enter and leave the anatomic structure. Because of this refraction or bending, the returning ultrasound waves may either appear to emanate from an incorrect location or miss the probe altogether. The existence of various, unpredictable air pockets between the probe and anatomic structure may be referred to as the lack of an effective acoustic coupling. A smaller number of air pockets between the probe surface and anatomic structure corresponds to a more effective acoustic coupling. 
     Third, when using past ultrasound probes, it is difficult to obtain steady probe contact with an organ while not deforming the organ or its blood flow, especially during intraoperative examination. Organ deformation occurs because past ultrasound probes placed a rigid probe surface against the soft organ tissue. In order to achieve an effective acoustic coupling, a probe user may firmly press the probe against the anatomic structure sought to be imaged. This deformation adversely affects ultrasound image quality because an anatomic structure sought to be imaged may be deformed to an unnatural shape or the velocity of blood flow may be altered due to deformation. The alteration of blood flow may be a particular problem where blood flow pattern and/or velocity are sought to be imaged. 
     Past ultrasound technology has not presented an ultrasonic probe that can avoid the aforementioned problems of organ movement during intraoperative ultrasound examination, the lack of an effective acoustic coupling, and deformation. 
     A need has long existed for such a probe. A further need remains for an improved ultrasonic probe housing that enables a physician to accurately determine and maintain the position of the probe during use. A need also remains for an improved ultrasonic probe housing that allows the physician to move the probe while maintaining its orientation without having to view the probe to ensure it is oriented properly. It is an object of the present invention to meet these needs. 
     BRIEF SUMMARY OF THE INVENTION 
     In an exemplary embodiment of the invention, an ultrasonic probe is provided. The probe includes a base member and an ultrasonic transducer housed by the base member. The probe also includes an intermediary damping member secured to the base member. The damping member includes an interior cavity for receiving an acoustic coupling fluid. The probe may optionally be secured to a flexible intermediary buffer. In another exemplary embodiment of the invention, a coupling member is secured to the base member. The coupling member includes an interior cavity for receiving an acoustic coupling fluid. The coupling member also includes a malleable contacting surface for contacting an anatomical structure during use. An alternative embodiment of the invention includes a transducer housing, an ultrasonic transducer mounted in the housing, and a flexible cushioned pad directly secured to a periphery of the transducer housing. Another alternative embodiment includes a pliable damping member defining an interior for retaining a fluid and structure for secured the damping member to an ultrasonic probe. 
    
    
     BRIEF DESCRIPTION OF THE SEVERAL DRAWINGS 
     FIG. 1 is a perspective view of a probe and handle housing according to a particular embodiment of the present invention. 
     FIG. 1A is a side view of the probe and handle housing, showing the base and first stem portion diagrammatically. 
     FIG. 1B is a top plan of the probe and handle housing. 
     FIG. 1C is a perspective view of the probe and handle housing base. 
     FIG. 2 is a perspective view of the planes in which the axes of the probe and handle housing base, first stem portion, and second stem portion reside. 
     FIG. 3 is a perspective view of the planes in which the axes of the first and second stem portions reside. 
     FIG. 4 is a top plan of the probe and handle housing according to an alternative embodiment of the present invention. 
     FIG. 5 is a perspective view of the probe and handle housing. 
     FIG. 6 is a top view of the probe and handle housing being implemented intraoperatively according to a particular embodiment of the present invention. 
     FIG. 7 is a top plan of the probe handle with the probe base shown schematically. 
     FIG. 8 is a side view of the cushion and probe and handle housing base with the probe stem shown schematically. 
     FIG. 9 is a perspective view of an ultrasonic probe and cushion. 
     FIG. 10 is a side view of an ultrasonic probe and cushion removably attached to the probe, with the probe shown schematically in part. 
     FIG. 11 is a front view of an ultrasonic probe and cushion removably attached to the probe, with the probe shown schematically in part. 
     FIG. 12 is a front view of the ultrasonic probe and cushion according to an alternative embodiment of the present invention. 
     FIG. 13 is a side view of an ultrasonic probe and cushion according to an alternative embodiment of the present invention. 
     FIG. 14 is a side view of an ultrasonic probe and cushion according to an alternative embodiment of the present invention. 
     FIG. 15 is a side view of a cushion and peel-away cover according to an alternative embodiment of the present invention. 
     FIG. 16 is a side view of a cushion according to an alternative embodiment of the present invention. 
     FIG. 17 is a cross-section of a cushion attached to a probe base member according to an alternative embodiment of the present invention. 
     FIGS. 18 and 19 are cross-sections of a probe base member according to alternative embodiments of the present invention. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     This application is a continuation-in-part of Application No. 09/233,403, filed Dec. 30, 1998, the subject matter of which is hereby incorporated in its entirety by reference. 
     FIG. 1 illustrates an ultrasonic probe and handle housing  100 . The housing includes a base  102  and a stem extending from the base for handling the probe. The stem includes a first stem portion  104  and a second stem portion  106 . A probe cable  107  extends from the second stem portion  106 . 
     FIG. 1A illustrates a view of the base  102  and first stem portion  104  of the housing  100 . The longitudinal axis of the base  108 , the longitudinal axis of the first stem portion  110 , and the inclined angle  112  at which the two axes intersect are also shown. 
     Turning to FIG. 1B, a top view of the probe and handle housing  100  is presented. The longitudinal axis along which the first stem portion extends  110 , the longitudinal axis along which the second stem portion extends  114 , and the angle  116  at which the axes intersect are shown. 
     Turning back to FIG. 1, a base  102  is provided for use with ultrasonic imaging technology. In the present embodiment, the lower surface of the probe is rectangular in shape, although this is not required. The first stem portion  104  extends from the base  102 . The first stem portion  104  may extend from the base  102  in one of several methods such as, for example, the stem portion  104  may be affixed to the base  102  or the stem portion  104  and base  102  may be integrally molded. The first stem portion  104  may extend from the base  102  at any portion of the base  102 , including at the center of the upper face of the base  102 . 
     Referring still to FIG. 1, a second stem portion  106  is merged with the first stem portion  104 , preferably to the section of the first stem portion opposite the section of the first stem portion that extends from the base  102 . The second stem portion  106  may be merged with the first stem portion  104  using one of several methods such as, for example, the second stem portion  106  may be affixed to the first stem portion  104  or the first and second stem portions  104 ,  106  may be integrally molded. 
     Preferably, the first and second stem portions  104 ,  106  are rigid. To meet this preferred construction, the stem portions  104 ,  106  may be made of, for example, a hard plastic. If the probe housing is suited for use, for example, as an intraoperative probe housing, the housing  100  should be suitable for use in a sterile environment, such as in an operating room during surgery. 
     As shown in FIG. 1A, the first stem portion  104  in this embodiment extends from the base  102  so that the first stem portion  104  extends along a longitudinal axis  110 . The longitudinal axis  110  of the first stem portion  104  preferably forms an inclined angle  112  with respect to the longitudinal axis  108  of the base, as shown in FIG.  1 A. This relationship between the longitudinal axes of the base  108  and first stem portion  110  permits, for example, the front portion of the base  102  to extend under a portion of unincised skin during an operation, as shown in FIG. 6. A physician may therefore obtain ultrasonic image information about anatomical structures above which the skin has not been cut. This relationship also permits the physician using the probe to be able to more accurately determine the position of the probe relative to the anatomical structure being monitored since the stem portions  104 ,  106  form a handle for the physician to hold onto the probe during usage. As a result, the physician is able to maintain an accurate sense of direction of the ultrasound beam and its relative position to the anatomical structure the physician is imaging. Additionally, if, for example, the probe handle were to extend from the base at a perpendicular angle (i.e., vertically with respect to the base), the physician&#39;s fingers would be more likely to get in the way of the physician&#39;s line of sight to the portion of the body being monitored. 
     As shown in FIG. 1B, the second stem portion  106  is, in the illustrated embodiment, merged with the first stem portion  104  so that the second stem portion  106  extends along a longitudinal axis  114 . The longitudinal axis  114  of the second stem portion preferably forms an inclined angle  116  with respect to the longitudinal axis  110  of the first stem portion, as shown in FIG.  1 B. This relationship between the first and second stem portions  104 ,  106  permits the physician using the probe to more accurately determine the position of the probe relative to the anatomical structure being monitored than if only a first stem portion were present. Specifically, the inclined angle  116  permits the physician to accurately maintain the orientation of the probe while viewing, for example, a monitor displaying an output from the probe. The angulation of the second stem portion  106  also allows the physician to hold the probe, at least in part, by the second stem portion  106  without placing his or her fingers in the line of sight to the base of the probe. 
     Turning now to FIGS. 1C,  2  and  3 , FIG. 1C presents the base  102  of the housing  100 , including the longitudinal axis of the base  108 , the lateral axis of the base  118 , and the plane  120  in which the longitudinal and lateral axes may reside. FIG. 2 illustrates the inclined plane  200  in which the first and second stem portions  104 ,  106  may reside. Also presented are the line of intersection  202  of these two planes, the angle of intersection  204  of these two planes, and the longitudinal axis of the second stem portion  205  (which, in FIG. 2, resides in the inclined plane  200 ). FIG. 3 presents the planes in which the axes of the base  120 , first stem portion  300 , and second stem portion  302  may reside. 
     As shown in FIG. 1C, the base  102  may be constructed such that the lateral  118  and longitudinal  108  axes of the base reside in a first plane  120 . Preferably, the first stem axis  104  extends from the base in a second plane  300 , shown in FIG. 3, that is substantially perpendicular to the first plane  120 , in which the axes of the base  108 ,  118  reside. This perpendicular relationship between the planes  120 ,  300  permits the probe to be used in a manner that will cause minimal agitation, including tearing, to an incised portion of the tissue during, for example, intraoperative use, as can be seen from FIG.  6 . 
     In the preferred construction, the second stem portion  106  resides in a third plane  302  that forms an inclined angle  304  with the first plane and an inclined angle  306  with the second plane, as shown in FIG.  3 . That is, the second stem portion  106  preferably extends, at least in part, laterally away from the second plane  300  while it extends, at least in part, vertically away from the base  102  of the probe. 
     In the embodiment illustrated in FIG. 2, the first and second stem portions  104 ,  106  lie in an inclined plane  200  with respect to the plane  120  in which the longitudinal and lateral axis of the base reside. The inclined plane  200  intersects the first plane  120  along a line  202  parallel to the lateral axis of the base. That is, the first and second stem portions  104 ,  106  in this embodiment gradually move away from the base at a constant, inclined angle  202 , even after the transition from the first stem portion  104  to the second stem portion  106  (shown by angle  116 ). 
     Turning now to FIGS. 4 and 5, those Figures present a probe and handle housing  400  including a base  102  and a handle  402  according to another embodiment of the invention. The illustrated base  102  is elongated and has longitudinal  108  and lateral  118  axes. The handle  402  of the housing  400  has a proximal end  404  and a distal end  406 . The proximal end  404  of the handle is coupled to the base  102 . The distal end  406  of the handle, however, extends away from the base  102  in a lateral direction with respect to the longitudinal axis  108  of the base. In the illustrated embodiment, the handle  402  is curvilinear in shape and, in fact, forms a continuous curvilinear profile. 
     As with a previously-referenced embodiment, this shape permits the physician to be able to more accurately determine where the probe is positioned relative to the anatomical structure being imaged. Specifically, if the physician grips the handle  402  near the distal end  406 , the physician may have an unobstructed view of the proximal end  404  of the handle and, more importantly, of the base  102  of the probe. Additionally, in the illustrated embodiment of FIG. 5, the handle  402  has a substantially hollow interior  500 . The substantially hollow interior  500  permits, for example, the multifilament cable shown in FIG. 5 to lead to a connector suitable for connecting the probe to an ultrasonic diagnostic system which drives the transducer of the probe and receives ultrasonic echo signals from the transducer. The probe cable  107  shown in FIG. 1 may be provided, for example, to contain the multifilament cable. 
     Preferably, the distal end  406  of the handle extends away from the base  102  at an inclined angle with respect to the base  102 . When the probe is used intraoperatively, this shape permits the physician to more easily grip the handle  402  of the probe without agitating or interfering with the incised area of the patient. The probe may also be formed such that the proximal end  404  of the handle extends away from the base  102  at an inclined angle with respect to the base. Preferably, both the proximal  404  and distal  406  ends extend away from the base at an inclined angle. This preferred structure permits as short of a handle  402  as possible while still allowing the physician to properly grip the handle  402  without obstructing the physician&#39;s view of the probe. 
     In the illustrated embodiment of FIG. 4, the longitudinal and lateral axes  108 ,  118  of the base reside in a first plane  120 . The proximal end  404  initially extends from the base  102  in a second plane  300  that is approximately perpendicular to the first plane, as shown in FIG.  3 . When used intraoperatively, this illustrated structure permits the handle to extend from the probe in a manner causing minimal agitation of the incised area of the patient, similarly to the embodiment shown in FIG.  6 . In the illustrated embodiment, the distal end  406  of the handle lies in an inclined plane that intersects the first plane along a line of intersection that is parallel to the lateral axis of the base; for example, the inclined plane  200  shown in FIG.  2 . 
     In the present embodiment, the handle  402  may be formed by multiple handle portions, such as the first  700  and second  702  handle portions of FIG. 7, that intersect at an obtuse angle  704 . As a result, it can be seen that a handle  402  according to the present invention may be partially curved in shape and partially straight. 
     According to yet another embodiment of the invention, whichever of the aforementioned configurations is used, a cushion  800  may be removably affixed to the base  102 , as shown in FIG.  8 . The cushion  800  may be adapted to contain a fluid  802 . The fluid  802  contained within the cushion  800  may be composed of a material having a similar sound velocity to anatomical tissue, thereby permitting the ultrasound probe to obtain a better image of the anatomical structure sought to be imaged. Other purposes for the cushion  800  of the present invention will be further discussed below. First, the cushion  800  provides acts as a “pillow” because it provides a damping effect between a pulsing anatomical structure and the probe. The pulsing may be caused by, for example, blood pulsation. Second, the cushion  800  improves the acoustic coupling between a fixed (usually flat) surface of a probe and an often curved and/or irregularly shaped anatomical structure, such as a heart, artery, or other organ. The cushion  800 , with the fluid  802  contained therein, is preferably pliable so that the damping and coupling can be effected. 
     The cushion  800  shown in FIG. 8 is balloon-shaped, having a neck portion  804  and a bag portion  806 . Although this shape is not required, when the cushion  800  is so shaped, the neck portion  804  may be removably affixed to the base. In the illustrated embodiment of FIG. 8, the inner perimeter of the neck portion  804  receives the lower surface of the base  102 . Preferably, a substantially fluid-impermeable seal is formed where the neck portion  804  is removably affixed to the base  102 . Additionally, in the illustrated embodiment, it is the bag portion  806  of the cushion  800  that is adapted to contain a fluid  802 . 
     Whichever of the embodiments is used, however, the handle may also be constructed so that it does not have a substantially hollow interior. The probe cable  107  may exit the handle closer to the base  102  than illustrated in FIG.  1 . Alternatively, the probe cable  107  may exit the base  102  separately from the handle (not pictured). The handle may also be removably affixed to the base  102 , so that the handle can be detached from the base  102 . Moreover, the handle may be formed such that it is flexible and bendable to a user desired shape. 
     FIG. 9 illustrates a perspective view of an ultrasonic probe  900  having a base member  902  with an undersurface  903  which houses an ultrasonic transducer  1702  (as illustrated in FIG.  17 ), and a pliable cushion  904  according to an alternative embodiment of the present invention. The base member  902  is elongated and includes four sidewalls  905 . The sidewalls  905  include a groove  906  extending horizontally around the perimeter of the base member  902 . The groove  906  is located at an intermediate section of the base member  902 , for example approximately one-half way between the undersurface  903  and the top of the base member  902 . The perimeter of the illustrated sidewalls  905  is substantially rectangular in shape. FIG. 10 discloses a side view of the probe  900  and cushion  904 . FIG. 11 discloses a front view of the probe  900 . As shown in FIG. 11, the groove  906  may be a square groove, formed at right angles with respect to the probe base member sidewalls  905 . 
     The illustrated cushion  904  or pad includes a flexible bag portion  908 , a neck portion  910 , and includes an interior cavity  911 . In the preferred embodiment, the cushion  904  includes an elastic member, for example an elastic band  912  as shown in FIG. 9, attached to the neck portion  910  of the cushion  904 . The cushion  904  shown in FIG. 9 also includes an undersurface  913  and an aperture  914  through the neck portion  910 . FIG. 9 also illustrates an optional fluid receptacle  916  and an inner surface  918  of the cushion  904 . 
     In order to use the ultrasonic probe  900  with the cushion  904 , the cushion  904  is filled with a fluid, for example through the aperture  914 . Optionally, the cushion  904  may be filled through a resealable fluid receptacle  916  which may allow a needle or similar object to penetrate the cushion  904  to fill the cushion  904  with an acoustic coupling fluid  802 . Optionally, the cushion  904  may be filled with a fluid  802  through a tunnel  1002 , in the base member  902  and/or other portions of the probe  900 , having a receptacle  1004  at one end of the tunnel  1002  for insertion of a fluid, as shown in FIG.  10 . In this alternative embodiment, the base member  902  includes on its undersurface  903  an aperture  1006  at the opposite end of the tunnel  1002  for transmitting a fluid  802  to the cushion  904 . Optionally, the cushion  904  may be manufactured and shipped containing the fluid  802  and having a peel-away cover  1502  that may be removed prior to use to permit the pad  904  to be secured to the base member  902 , as shown in FIG.  15 . 
     Either before or after the cushion  904  is filled with a fluid  802 , the pad  904  is secured to the base member  902  by placing the transducer of the probe  900  through the aperture  914  in contact with the fluid. The elastic band  912  is inserted into the groove  906 , as shown in FIGS. 10 and 17. Optionally, the cushion  904  may be secured to the base member  902  by alternate means, for example by tying, clamping or strapping the cushion  904  to the base member  902 . For example, as shown in FIG. 13, the cushion  904  is strapped to the probe  900  by one or more straps  1302 . In the embodiment illustrated by FIG. 13, the cushion  904  may also be equipped with an additional device for maintaining a fluid-impermeable seal with the base member  902 . Optionally, the cushion  904  may be made from an elastic material and the cushion  904  may be secured to the probe  900  simply by stretching the neck portion  910  of the pad  904  around the base member  902 , as shown in FIG.  8 . Optionally, the sidewalls  905  of the base member  902  may be shaped to form a trapezoid, step or other structure for securing the cushion  902  to the probe  900 . FIG. 18 illustrates a trapezoidal shaped base member  1802 , which includes an upper cross-section α and a lower long cross-section β to assist in retaining a cushion  904  to the base member  902 . FIG. 19 illustrates a square step  1902  along the base of the sidewall  902  to assist in retaining a cushion  904  to the base member  902 . 
     The cushion  904  may be made of any one or more of a number of pliable materials. Preferably, the material should be able to retain a fluid and be able to stretch to fit around the perimeter of the base member. The material preferably has acoustical qualities such that it does not substantially interfere with the transmitted and received ultrasonic waves. Exemplary materials include latex, vinyl, nitrile and ELASTYREN®. ELASTYREN® is a substitute for latex for those who are allergic to latex and is manufactured by ECI Medical Technologies, Inc. in Bridgewater, Nova Scotia, Canada. 
     The cushion  904  may be removably affixed to the base, as shown in FIGS. 8,  10  and  11 . A fluid compartment  908  is created between the bottom surface  903  of the base member  902  and the inner surface  918  of the cushion  904 . Optionally, the cushion  904  may envelop the entire base member  902  and a portion of the stem, as shown in FIG.  14 . The cushion  904  may be secured to the probe stem by using a strap  1402 , for example a VELCRO® strap. Preferably, the fluid contained within the cushion  904  is composed of a material having a similar sound velocity to anatomical tissue (or at least a sound velocity that does not adversely affect the ultrasonic waves). This permits the ultrasound probe  900  to obtain a better image of the anatomical structure sought to be imaged. The illustrated cushion  904  can be filled with sterile water or a gel. Sterile water is preferred because the preferred cushion  904 , when filled immediately prior to usage, does not need to be shipped and stored while containing a fluid (and therefore is not susceptible to evaporation). The use of water instead of gel is beneficial because water has a sound velocity that is more similar to anatomical tissue than are gels. 
     During use, the cushion  904  acts as a pillow or cushion to dampen forces and motion external to the probe, such as during intraoperative use. Such external forces may include pulsing anatomical structures, for example the heart, other organs or other tissue related to the pressure side of the blood system. External forces or motion may also include motion during muscle activation. The cushion  904  also improves the acoustical coupling between a fixed surface of the base member  902  and an often curved and/or irregularly shaped anatomical structure, such as a heart, artery, or other organ. Specifically, the cushion  904  conforms to the shape of the anatomical tissue, thereby eliminating air pockets between the probe  900  and tissue and improving the ultrasound image quality. Without the pliable cushion  904 , the rigid undersurface  903  of the illustrated base member  902  might deform the organ and/or its blood flow when pressed against the organ, thereby adversely affecting ultrasound image quality. For this reason, the cushion  904 , with the fluid  802  contained therein, is preferably pliable so that the damping and coupling can be effected. During use, the undersurface  913  of the cushion  904  may contact the anatomic structure sought to be imaged. The pliable cushion  904  will deform according to the pressure placed on the pad by the organ, thus compensating for the movement of the organ and the probe  900  while still obtaining an acoustic coupling for the ultrasound energy. 
     The cushion  904  shown in FIGS. 8,  9  and  10  is balloon-shaped, having a neck portion  910  and a bag portion  908 . Although this shape is not required, when the cushion  904  is so shaped, the neck portion  910  may be removably affixed to the base  902 , for example as discussed above. In the illustrated embodiment of FIG. 8, the inner perimeter of the neck portion  910  receives the lower surface of the base  902 , and thus no elastic member is needed. Preferably, a substantially fluid-impermeable seal is formed where the neck portion  910  is removably affixed to the base  902 , regardless of whether an elastic member is used. Additionally, in the illustrated embodiment of FIG. 8, it is the bag portion of the cushion pad  904  that is adapted to contain a fluid  802 . Optionally, the cushion  904  may contain a sealing member  1602  on the interior  911  of the cushion  904  below the neck portion  910  of the cushion  904 . If a sealing member  1602  is used, the undersurface  903  of the base member  902  is preferably placed in direct contact with the sealing member  1602  during use (to avoid the existence of air pockets between the base member  902  and the anatomic structure). 
     Turning now to FIG. 12, that Figure presents an alternative embodiment of an ultrasound probe  1200  wherein the base member  1201  includes a ridge  1202  for securing a cushion  904  to the base member  1201 . The ridge  1202  may be used for affixation of a pliable cushion  904  having an elastic member to the base member  1201 . Optionally, a pliable pad may have a rigid ring at its neck portion shaped to form a snap fit with the ridge  1202 . 
     While particular embodiments of the invention have been shown, it will be understood, of course, that the invention is not limited thereto since modifications may be made by those skilled in the art, particularly in light of the foregoing teachings. For example, although the invention is at times discussed as being used intraoperatively, the invention is not limited to intraoperative probes. Moreover, although the invention is shown in FIGS. 9-11 as having a multi-angled handle, the one of many different types of handles invention is not limited thereto since it may be used with an ultrasound probe having one of many type of handle, for example as indicated in FIGS. 8 and 12. It is, therefore, contemplated that the appended claims will cover any such modifications as incorporate those features which constitute the essential features of these improvements within the true spirit and the scope of the invention.