Abstract:
An ultrasound energy emitting apparatus is disclosed. The ultrasound energy emitting apparatus comprises a hand-held enclosure and a plurality of ultrasound transducers disposed on that enclosure, or disposed within and extending outwardly from the enclosure. The plurality of ultrasound transducers can be operated simultaneously, or in a programmed fashion whereunder one or more of, but fewer than all, of the transducers emit ultrasound energy at one time.

Description:
CROSS REFERENCE TO RELATED CASES  
       [0001]    This application claims priority from a U.S. Provisional Application having Ser. No. 60/578,954 filed Jun. 10, 2004. 
     
    
     FIELD OF THE INVENTION  
       [0002]    Applicants&#39; invention relates to an ultrasound emitting device, and a method using same. 
       BACKGROUND OF THE INVENTION  
       [0003]    Thrombosis, the formation and development of a blood clot or thrombus within the vascular system, can be life threatening. The thrombus can block a vessel and stop blood supply to an organ or other body part. If detached, the thrombus can become an embolus and occlude a vessel distant from the original site. 
         [0004]    Dissolution of thrombus using ultrasound is known in the art. Further, the ability of microbubbles to potentiate ultrasound-induced thrombolysis is known. The bubbles are destroyed by the ultrasound and the energy is released into the clot. 
         [0005]    What is needed, however, is an ultrasound emitting device which can better direct the emitted ultrasound energy to the occlusion site, thereby enhancing the effectiveness of the ultrasound energy/microbubble interaction. Applicants&#39; apparatus provides such an ultrasound emitting device. 
         [0006]    Prior art therapeutic ultrasound emitting devices comprise a single ultrasound transducer. In contrast, Applicants&#39; apparatus comprises a plurality of ultrasound transducers. Applicants&#39; plurality of ultrasound transducers can be operated simultaneously, or in a programmed fashion whereunder one or more of, but fewer than all, of the transducers emit ultrasound energy at one time. 
       SUMMARY OF THE INVENTION  
       [0007]    Applicants&#39; invention comprises an ultrasound energy emitting apparatus. Applicants&#39; ultrasound energy emitting apparatus comprises a hand-held enclosure and a plurality of ultrasound transducers disposed on that enclosure, or disposed within and extending outwardly from the enclosure. Applicants&#39; plurality of ultrasound transducers can be operated simultaneously, or in a programmed fashion whereunder one or more of, but fewer than all, of the transducers emit ultrasound energy at one time. Applicants&#39; invention further comprises a method using Applicants&#39; apparatus to treat a patient having an occlusion lodged in a blood vessel. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS  
         [0008]    The invention will be better understood from a reading of the following detailed description taken in conjunction with the drawings in which like reference designators are used to designate like elements, and in which: 
           [0009]      FIG. 1A  is a perspective view of Applicants&#39; hand-held ultrasound emitting device; 
           [0010]      FIG. 1B  is a side view of the device of  FIG. 1 ; 
           [0011]      FIG. 1C  is a perspective view of the device of  FIG. 1  showing a housing portion and a bottom portion; 
           [0012]      FIG. 2A  is a perspective view of an embodiment of Applicants&#39; hand-held ultrasound emitting device comprising a bottom portion comprising two offset planar members; 
           [0013]      FIG. 2B  is a perspective view of the bottom portion of  FIG. 2A ; 
           [0014]      FIG. 2C  is a side view of the bottom portion of  FIG. 2A ; 
           [0015]      FIG. 3A  is a perspective view of an embodiment of Applicants&#39; hand-held ultrasound emitting device comprising a bottom portion comprising four offset planar members; 
           [0016]      FIG. 3B  is a side view of the bottom portion of  FIG. 3A ; 
           [0017]      FIG. 4A  is a block diagram showing one embodiment of Applicants&#39; sound head matrix; 
           [0018]      FIG. 4B  is a side view of one embodiment of the sound head matrix of  FIG. 4A ; 
           [0019]      FIG. 4C  is a side view of a second embodiment of the sound head matrix of  FIG. 4A ; 
           [0020]      FIG. 5A  is a block diagram showing a second embodiment of Applicants&#39; sound head matrix; 
           [0021]      FIG. 5B  is a side view of one embodiment of the sound head matrix of  FIG. 5A ; 
           [0022]      FIG. 5C  is a side view of a second embodiment of the sound head matrix of  FIG. 5A ; 
           [0023]      FIG. 6  is a perspective view showing an external controller and power source for Applicants&#39; hand-held ultrasound emitting device; 
           [0024]      FIG. 7A  is a perspective view showing an embodiment of Applicants&#39; hand-held ultrasound emitting device comprising an internal controller; 
           [0025]      FIG. 7B  is a perspective view showing the device of  FIG. 7A  in combination with an integrated input/output element; 
           [0026]      FIG. 8A  is a block diagram showing an embodiment of Applicants&#39; hand-held ultrasound emitting device which further comprises a diagnostic ultrasound transceiver; 
           [0027]      FIG. 8B  is a perspective view of the device of  FIG. 8A  further comprising an internal controller; 
           [0028]      FIG. 8C  is a perspective view of the device of  FIG. 8B  further comprising an integrated input/output element; 
           [0029]      FIG. 8D  is a perspective view of the device of  FIG. 8C  as that device is positioned with respect to venus blood flow; 
           [0030]      FIG. 8E  is a perspective view of the device of  FIG. 8A  further comprising an integrated controller comprising an auto-detect function; 
           [0031]      FIG. 9  is a flow chart summarizing the steps of Applicants&#39; method using Applicants&#39; hand-held ultrasound emitting device; 
           [0032]      FIG. 10  is a chart reciting the depth from skin surface of certain veins for a first patient; 
           [0033]      FIG. 11  is a chart reciting the depth from skin surface of certain veins for a second patient; 
           [0034]      FIG. 12  is a chart reciting the depth from skin surface of certain veins for a third patient; 
           [0035]      FIG. 13  is a perspective view showing an occlusion site in a blood vessel; 
           [0036]      FIG. 14A  is a block diagram showing the ultrasound emissions from an offset sound head matrix comprising two planar assemblies; 
           [0037]      FIG. 14B  shows the convergence point for the device of  FIG. 14A ; 
           [0038]      FIG. 15A  is a block diagram showing the ultrasound emissions from an offset sound head matrix comprising three planar assemblies; 
           [0039]      FIG. 15B  shows the convergence point for the device of  FIG. 15A ; 
           [0040]      FIG. 16A  is a block diagram showing the ultrasound emissions from an offset sound head matrix comprising four planar assemblies; 
           [0041]      FIG. 16B  shows the convergence point for the device of  FIG. 16A ; 
           [0042]      FIG. 17  is a bottom view of Applicants&#39; hand-held device showing certain attachment means used to attach the device to a patient&#39;s extremity; 
           [0043]      FIG. 18  is a side view showing Applicants&#39; hand-held ultrasound emitting device and an ultrasound coupling medium positioned on the skin surface over an occlusion site. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0044]    This invention is described in preferred embodiments in the following description with reference to the Figures, in which like numbers represent the same or similar elements. The invention will be described as embodied in a hand-held ultrasound emitting device having a curved top portion. The following description of Applicant&#39;s apparatus, and method using that apparatus, is not meant, however, to limit Applicant&#39;s invention to hand-held devices having a curved top, or to only hand-held devices, as the invention herein can be applied to devices to production of ultrasound energy in general. 
         [0045]    Referring to  FIG. 1A , Applicants&#39; hand-held ultrasound emitting device  100  comprises a top  110 , bottom  120 , and sides  130 ,  140 ,  150 , and  160 . In certain embodiments, top  110  and sides  130 ,  140 ,  150 , and  160 , are formed from one or more rigid materials, including wood, metal, plastic, and combinations thereof. In certain embodiments, top  110 , and sides  130 ,  140 ,  150 , and  160 , are separately formed, and subsequent attached to one another as shown in  FIG. 1  using conventional attachment methods, including welding, sonic welding, plastic welding, adhesive bonding, mechanical attachment, and the like. 
         [0046]    Sides  140  and  160  have dimension  142  in the Y direction. In certain embodiments, dimension  142  is between about 10 cm and about 50 cm. Sides  130  and  150  have dimension  132  in the X direction. In certain embodiments, dimension  132  is between about 5 cm and about 25 cm. 
         [0047]      FIG. 1B  is a side view of apparatus  100 . Apparatus  100  includes a plurality of therapeutic ultrasound transducers  180  disposed on, or through, bottom  120 . By “therapeutic ultrasound transducer,” Applicants mean a device that is capable of operating at between a 0.1 percent and a 100 percent duty cycle, and that emits therapeutic ultrasound energy. By “therapeutic ultrasound energy,” Applicants mean sound waves having a frequency between about 150 kilohertz and about 10 megahertz or higher, and a power level between about 0.1 watt/cm 2  and about 30 watts/cm 2 . In certain embodiments, when operated continuously, the output power for each of the plurality of therapeutic ultrasound transducers can as great as about 50 watts. In other embodiments, the output power for each of the plurality of therapeutic ultrasound transducers is between about 6 to about 10 watts. 
         [0048]    In the illustrated embodiment of  FIG. 1B , sides  130  and  150  vary in dimension along the Z direction, having dimension  134  at the attachment of sides  140  and  160 , and dimension  136  at mid point  138 . In certain embodiments, dimension  134  is between about 2 cm and about 4 cm. In certain embodiments, dimension  136  is between about 3 cm and about 8 cm. In other embodiments, Applicants&#39; hand-held ultrasound emitting device comprises a parallelepiped, i.e. dimension  132  is substantially equal to dimension  134 . 
         [0049]    Referring to  FIG. 1C , in certain embodiments Applicants&#39; hand-held ultrasound emitting device  100  comprises housing  170  which includes top  110  and sides  130 ,  140 ,  150 , and  160 . In certain embodiments, housing  170  is integrally formed from one or more metallic materials. In certain embodiments, housing  170  is integrally molded from one or more polymeric materials. In certain embodiments, housing  170  is formed from one or more full density polymeric materials. In certain embodiments, those polymeric materials include polyethylene, polypropylene, polycarbonate, polystyrene, polyvinylchloride, combinations thereof, and the like. 
         [0050]    In certain embodiments, those polymeric materials comprise one or more partial-density materials, i.e. one or more cellular materials. In certain embodiments, such cellular materials comprise one or more structural foam materials formed from the group which includes one or more polyurethanes, one or more polystyrenes, and combinations thereof, and the like. 
         [0051]    Bottom  120  in combination with housing  170  comprises an enclosure. Bottom  120  includes interior surface  122  and exterior surface  124 . In certain embodiments, bottom  120  is formed from metal, one or more polymeric materials, and combinations thereof. In certain embodiments, housing  170  is formed from one or more first polymeric materials and bottom  120  is formed from one or more second polymeric materials, where the one or more first polymeric materials differ from the one or more second polymeric materials. 
         [0052]    In certain embodiments, bottom  120  is attached to housing  170  using adhesive bonding. In certain embodiments, bottom  120  is attached to housing  170  using conventional attachment means such as, for example, screws, nuts/bolts, rivets, and the like. In certain embodiments, bottom  120  can be releaseably affixed to housing  170 , such that housing  170  can be used with a variety of differing sound head matrix assemblies, as described below. 
         [0053]    A plurality of piezoelectric transducers are disposed on, or through, the exterior surface of the bottom portion of Applicants&#39; device. Each piezoelectric transducer, sometimes referred to as a “sound head,” includes one or more piezoelectric materials. When an alternating current is applied to such a piezoelectric material, deformation occurs wherein the peizoelectric material expands and contracts. Such expansion and contraction crystal produces vibrations, i.e. sound waves. 
         [0054]    In certain embodiments, Applicants&#39; piezoelectric transducers comprise one or more ceramic materials having pronounced piezoelectric characteristics. In certain embodiments, Applicants&#39; piezoelectric transducers comprise lead zirconate titanate (“PZT”). In other embodiments, Applicants&#39; piezoelectric material comprises lead-magnesium-niobate lead titanate, hereafter referred to for brevity by the acronym PMN-PT. Such PMN-PT materials are described in U.S. Pat. No. 6,737,789. 
         [0055]    In certain embodiments, Applicants&#39; piezoelectric materials are formed from a thick-film ink, wherein one or more PZT and/or PMN-PT pastes are mixed with a powdered glass and an organic carrier, which is then printed onto the bottom portion of Applicants&#39; device. 
         [0056]    In certain embodiments, the plurality of piezoelectric transducers disposed on the exterior of Applicants&#39; device comprise therapeutic ultrasound transducers. By “therapeutic ultrasound transducer,” Applicants mean a device that is capable of operating at between a 0.1 percent and a 100 percent duty cycle, and that emits therapeutic ultrasound energy. By “therapeutic ultrasound energy,” Applicants mean sound waves having a frequency between about 150 kilohertz and about 10 megahertz or higher, and a power level between about 0.1 watt/cm 2  and about 30 watts/cm 2 . In certain embodiments, when operated continuously, the output power for each of the plurality of therapeutic ultrasound transducers can as great as about 50 watts. In other embodiments, the output power for each of the plurality of therapeutic ultrasound transducers is between about 6 to about 10 watts. 
         [0057]    The plurality of therapeutic ultrasound transducers disposed on Applicants&#39; device comprise a sound head matrix. In certain embodiments, Applicants&#39; sound head matrix comprises a plurality of therapeutic ultrasound transducers are arranged in columns and rows. 
         [0058]      FIG. 4A  shows one embodiment of Applicants&#39; sound head matrix. In the illustrated embodiment of  FIG. 4A , the sound head matrix comprises sixteen (16) therapeutic ultrasound transducers arranged in two columns of eight (8) transducers. Thus, sound head matrix of  FIG. 4A  comprises an 8×2 sound head matrix. 
         [0059]    Each transducer comprising the sound head matrix of  FIG. 4A  is disposed on, or through, one of two planar members, either planar member  420  or planar member  430 . In certain embodiments, planar member  420  and/or planar member  430  comprises a circuit substrate, wherein one or more electrical circuit components are attached to and/or through that circuit substrate. In certain embodiments, such a circuit substrate comprises what is sometimes referred to as a printed circuit board (“PCB”). In certain embodiments, planar member  420  and/or planar member  430  comprises a single-sided PCB. In certain embodiments, planar member  420  and/or planar member  430  comprises a double-sided PCB. In certain embodiments, planar member  420  and/or planar member  430  comprises a multilayer PCB. In certain embodiments, planar member  420  and/or planar member  430  comprises a metal core, i.e. copper for example, encapsulated with a ceramic coating. 
         [0060]    In certain embodiments, planar member  420  and/or planar member  430  comprise a ceramic material. In certain embodiments, planar member  420  and/or planar member  430  comprise aluminum oxide. In certain embodiments, planar member  420  and/or planar member  430  comprise beryllium oxide. 
         [0061]    In embodiments wherein housing  170  comprises one or more metallic components, and wherein planar members  420  and/or  430  comprise a ceramic material and/or a ceramic material encapsulating a copper core, planar members  420  and/or  430  conduct heat generated by the plurality of ultrasound emitters from the core of Applicants&#39; device to the metallic housing, i.e. the circuit substrates in combination with the housing, comprise, inter alia, an integrated heat sink assembly which continuously dissipates heat from Applicants&#39; hand-held device to the environment. 
         [0062]    Planar member  420  is continuously attached to planar member  430  at common edge  405 . Transducers  441 ,  442 ,  443 ,  444 ,  445 ,  446 ,  447 , and  448 , are disposed on, or through, surface  424  of planar member  420 . Transducers  441 ,  442 ,  443 ,  444 ,  445 ,  446 ,  447 , and  448 , in combination with planar member  420 , comprises planar assembly  460 . Transducers  451 ,  452 ,  453 ,  454 ,  455 ,  456 ,  457 , and  458 , are disposed on, or through, surface  434  of planar member  430 . Transducers  451 ,  452 ,  453 ,  454 ,  455 ,  456 ,  457 , and  458 , in combination with planar member  430 , comprises planar assembly  470 . 
         [0063]    Planar assembly  460  in combination with planar assembly  470  comprises sound head matrix assembly  401 . In certain embodiments, sound head matrix assembly  401  comprises a substantially flat structure. In other embodiments, sound head matrix assembly  401  is not flat, i.e. the dihedral angles formed by the intersection of assemblies  460  and  470  do not equal 180 degrees. 
         [0064]    Referring to  FIG. 2A , device  200  includes housing  170  ( FIG. 1C ) in combination with an “offset” embodiment of sound head matrix assembly  401 . As described above, sound head matrix assembly  401  includes planar assembly  460  in combination with planar assembly  470 , where planar assembly  460  is continuously joined to planar assembly  470  along common edge  405 . Planar assembly  460  lies in a first plane, and planar assembly  470  lies in a second plane. That first plane intersects the second plane along common edge  405  to form an interior dihedral angle, as defined herein, less than 180 degrees. 
         [0065]    Referring now to  FIGS. 2A and 2B , planar assembly  460  includes edge  422 . Planar assembly  470  includes edge  432 . Edge  422  meets edge  432  at seam  405 . Dotted line  250  represents the extension of edge  422  past seam  405 . As shown in  FIG. 2C , angle Φ represents the angle formed between edge  432  and extension line  250 . For purposes of this Application, planar assembly  460  is “offset” from planar assembly  470  by angle Φ. As those skilled in the art will. appreciate, the interior dihedral angle, in degrees, formed by the intersection of planar assembly  460  and planar assembly  470  is 180−Φ. 
         [0066]    In certain embodiments, angle Φ is between about 5 degrees and about 25 degrees. In certain embodiments, angle Φ is between about 10 degrees and about 20 degrees. In certain embodiments, angle Φ is about 13 degrees. 
         [0067]    As those skilled in the art will appreciate, the interior dihedral angle formed by planar assembly  460  and planar assembly  470  is inversely proportional to the offset angle Φ. Therefore, as Φ increases from 0 degrees, the dihedral angle decreases from 180 degrees. Thus, where planar assembly  460  is “offset” from planar assembly  470  by, for example, 15 degrees, then the interior dihedral angle formed by planar assembly  460  and planar assembly  470  is 165 degrees. 
         [0068]      FIG. 4B  shows a side view of apparatus  200  which includes housing  170  in combination with an offset sound head matrix assembly  401 . Transducer  441  comprises a first side  481  and an opposing second side  482 . Transducer  451  includes a first side  491  and an opposing second side  492 . In the illustrated embodiment of  FIG. 4B , side  481  of transducer  441  is disposed on surface  424  of planar member  420 , and side  491  of transducer  451  is disposed on surface  434  of planar member  430 . As those skilled in the art will appreciate, transducers  441  may include one or more leads which extend through holes, i.e. vias, drilled through planar member  420 . In other embodiments, transducer  441  comprises what is sometimes called a “surface mounted” device, wherein that surface mounted device is attached to a solder pad disposed on surface  424 . 
         [0069]      FIG. 4C  shows a side view of apparatus  201  which includes housing  170  in combination with an offset sound head matrix assembly  402 . Sound head matrix assembly  402  is identical to sound head matrix assembly  401  except that each of the plurality of therapeutic ultrasound transducers extends through a planar member rather than being disposed on that planar member. For example in the illustrated embodiment of  FIG. 4C , transducer  441  is disposed through planar member  420  such that surface  482  of transducer  441  is flush with surface  424  of planar assembly  460 . Similarly in this embodiment, transducer  451  is disposed through planar member  430  such that surface  492  of transducer  451  is flush with surface  434  of planar assembly  470 . 
         [0070]      FIG. 5A  shows another embodiment of Applicants&#39; sound head matrix. In the illustrated embodiment of  FIG. 5A , the sound head matrix comprises sixteen (16) therapeutic ultrasound transducers arranged in four columns of four transducers. Thus, sound head matrix of  FIG. 5A  comprises an 4×4 sound head matrix. 
         [0071]    Each transducer comprising the sound head matrix of  FIG. 5A  is disposed on, or through, one of four planar members, namely planar member  510 , or planar member  520 , or planar member  530 , or planar member  540 . Planar member  510  is continuously attached to planar member  520  at common edge  511 . Transducers  514 ,  515 ,  516 , and  517 , are disposed on, or through, surface  513  of planar member  510 . Transducers  514 ,  515 ,  516 , and  517 , in combination with planar member  510 , comprise planar assembly  550 . Angle  518  comprises the interior dihedral angle formed by the intersection of planar member  510  with planar member  520 . 
         [0072]    In certain embodiments, angle  518  is about 180 degrees. In these embodiments, planar member  510  is not offset from planar member  520 , i.e. planar member  510  in combination with planar member  520  comprises a substantially flat assembly. In other embodiments, angle  518  is less than 180 degrees, i.e. planar member  510  is offset from planar member  520 . 
         [0073]    In certain embodiments, planar members  510  and  520  are integrally formed to include angle  518 . In other embodiments, planar members  510  and  520  are individually formed, and subsequently attached using conventional attachment methods. 
         [0074]    Planar member  520  is continuously attached to planar member  530  at common edge  521 . Transducers  524 ,  525 ,  526 , and  527 , are disposed on, or through, surface  523  of planar member  520 . Transducers  524 ,  525 ,  526 , and  527 , in combination with planar member  520 , comprise planar assembly  560 . Angle  528  comprises the interior dihedral angle formed by the intersection of planar member  520  with planar member  530 . 
         [0075]    In certain embodiments, angle  528  is about 180 degrees. In these embodiments, planar member  520  is not offset from planar member  530 , i.e. planar member  520  in combination with planar member  530  comprises a substantially flat assembly. In other embodiments, angle  528  is less than 180 degrees, i.e. planar member  520  is offset from planar member  530 . 
         [0076]    In certain embodiments, planar members  520  and  530  are integrally formed to include angle  528 . In other embodiments, planar members  520  and  530  are individually formed, and subsequently attached using conventional attachment methods. 
         [0077]    Planar member  530  is continuously attached to planar member  540  at common edge  531 . Transducers  534 ,  535 ,  536 , and  537 , are disposed on, or through, surface  533  of planar member  530 . Transducers  534 ,  535 ,  536 , and  537 , in combination with planar member  530 , comprise planar assembly  570 . Angle  538  comprises the interior dihedral angle formed by the intersection of planar member  530  with planar member  540 . 
         [0078]    In certain embodiments, angle  538  is about 180 degrees. In these embodiments, planar member  530  is not offset from planar member  540 , i.e. planar member  530  in combination with planar member  540  comprises a substantially flat assembly. In other embodiments, angle  538  is less than 180 degrees, i.e. planar member  530  is offset from planar member  540 . 
         [0079]    In certain embodiments, planar members  530  and  540  are integrally formed to include angle  538 . In other embodiments, planar members  530  and  540  are individually formed, and subsequently attached using conventional attachment methods. 
         [0080]    Transducers  544 ,  545 ,  546 , and  547 , are disposed on, or through, surface  543  of planar member  530 . Transducers  544 ,  545 ,  546 , and  547 , in combination with planar member  540 , comprise planar assembly  580 . 
         [0081]    Planar assemblies  550 ,  560 ,  570 , and  580 , in combination, comprise sound head matrix assembly  501 . In certain embodiments, sound head matrix assembly  501  comprises a substantially flat structure. In other embodiments, sound head matrix assembly  501  is not flat. 
         [0082]    Referring to  FIGS. 3A and 3B , device  300  includes housing  170  ( FIG. 1C ) in combination with sound head matrix assembly  501 . Edge  512  of planar assembly  550  meets edge  522  of planar assembly  560  at seam  511 . Dotted line  355  represents the extension of edge  512  past seam  511 . As shown in  FIG. 3B , angle Φ represents the angle formed between edge  522  and extension line  335 . For purposes of this Application, planar assembly  550  is “offset” from planar assembly  560 , where the offset angle is angle Φ 1 . As those skilled in the art will appreciate, the interior dihedral angle, in degrees, formed by the intersection of planar assembly  550  and planar assembly  560  is 180−Φ 1 . By “interior dihedral angle,” Applicants&#39; mean the angle formed between surface  513  and surface  523 . 
         [0083]    In certain embodiments, angle Φ 1  is between about 5 degrees and about 25 degrees. In certain embodiments, angle Φ 1  is between about 8 degrees and about 15 degrees. In certain embodiments, angle Φ 1  is about 13 degrees. 
         [0084]    Edge  522  of planar assembly  560  meets edge  532  of planar assembly  570  at seam  521 . Dotted line  345  represents the extension of edge  522  past seam  521 . As shown in  FIG. 3B , angle Φ 2  represents the angle formed between edge  532  and extension line  345 . For purposes of this Application, planar assembly  560  is “offset” from planar assembly  570 , where the offset angle is angle Φ 2 . As those skilled in the art will appreciate, the interior dihedral angle, in degrees, formed by the intersection of planar assembly  560  and planar assembly  570  is 180−Φ 1 . By “interior dihedral angle,” Applicants&#39; mean the angle formed between surface  523  and surface  533 . 
         [0085]    In certain embodiments, angle Φ 2  is between about 5 degrees and about 25 degrees. In certain embodiments, angle Φ 2  is between about 8 degrees and about 15 degrees. In certain embodiments, angle Φ 2  is about 10 degrees. 
         [0086]    Edge  532  of planar assembly  570  meets edge  542  of planar assembly  570  at seam  531 . Dotted line  335  represents the extension of edge  532  past seam  531 . As shown in  FIG. 3B , angle Φ 3  represents the angle formed between edge  542  and extension line  335 . For purposes of this Application, planar assembly  570  is “offset” from planar assembly  580 , where the offset angle is angle Φ 3 . As those skilled in the art will appreciate, the interior dihedral angle, in degrees, formed by the intersection of planar assembly  570  and planar assembly  580  is 180−Φ 1 . By “interior dihedral angle,” Applicants&#39; mean the angle formed between surface  533  and surface  543 . 
         [0087]    In certain embodiments, angle Φ 3  is between about 5 degrees and about 25 degrees. In certain embodiments, angle Φ 3  is between about 8 degrees and about 15 degrees. In certain embodiments, angle Φ 3  is about 13 degrees. 
         [0088]    In certain embodiments, two or more of offset angles Φ 1 , Φ 2 , and/or Φ 3 , are substantially the same. By “substantially the same,” Applicants means within about plus or minus ten percent or less. In other embodiments, two or more of offset angles Φ 1 , Φ 2 , and/or Φ 3 , differ. 
         [0089]      FIG. 5B  shows a side view of apparatus  300  which includes housing  170  in combination with a multiply offset sound head matrix assembly  501 . Transducers  514 ,  524 ,  534 , and  544 , each comprise a first side  591 ,  593 ,  595 , and  597 , respectively, and an opposing second side  592 ,  594 ,  596 , and  598 , respectively. 
         [0090]    In the illustrated embodiment of  FIG. 5B , side  591  of transducer  441 , and side  593  of transducer  524 , and side  595  of transducer  534 , and side  597  of transducer  544 , respectively, are disposed on surface  513  of planar assembly  550 , surface  523  of planar assembly  560 , surface  533  of planar assembly  570 , and surface  543  of planar assembly  580 , respectively. Transducers  515 ,  516 ,  517 ,  525 ,  526 ,  527 ,  535 ,  536 ,  537 ,  545 ,  546 , and  547 , are similarly attached to their respective planar assemblies. 
         [0091]    As those skilled in the art will appreciate, the plurality of transducers comprising sound head matrix assembly  501  may include one or more leads which extend through holes, i.e. vias, drilled through one of the four planar assemblies. In other embodiments, the plurality of transducers comprising sound head matrix  501  each comprise what is sometimes called a “surface mounted” device, wherein that surface mounted device is attached to a solder pad disposed on surface  513 , or surface  523 , or surface  533 , or surface  443 . 
         [0092]      FIG. 5C  shows a side view of apparatus  301  which includes housing  170  in combination with an offset sound head matrix assembly  502 . Sound head matrix assembly  502  is identical to sound head matrix assembly  501  except that each of the plurality of therapeutic ultrasound transducers extends through a planar assembly rather than being disposed on the exterior surface of that planar assembly. For example in the illustrated embodiment of  FIG. 5C , transducers  514 ,  524 ,  534 , and  544 , respectively, are disposed through planar assembly  550 , planar assembly  560 , planar assembly  570 , and planar assembly  580 , respectively, such that surface  592  of transducer  514  is flush with surface  513  of planar assembly  550 , and, such that surface  594  of transducer  524  is flush with surface  523  of planar assembly  560 , and such that surface  596  of transducer  534  is flush with surface  533  of planar assembly  570 , and such that surface  598  of transducer  544  is flush with surface  543  of planar assembly  580 . 
         [0093]      FIG. 6  shows one embodiment of Applicants&#39; therapeutic ultrasound apparatus  600 . Apparatus  600  includes hand-held ultrasonic device  610 , external controller  620 , and power source  650 . Power source  650  provides power to device  610  by power cable  660 . In certain embodiments, Applicants&#39; system  600  includes power switch  665 . In the illustrated embodiment of  FIG. 6  power switch  665  is disposed in power cable  660 . In other embodiments, switch  665  is disposed on power source  650 . In other embodiments, switch  665  is disposed on the outer surface of device  610 . Power switch  665  can comprise any suitable power switching device, and may take the form of, for example, a rocker switch, a toggle switch, a push to operate switch, and the like. 
         [0094]    Device  610  includes housing  170  and sound head matrix assembly  605 . In the illustrated embodiment of  FIG. 6 , Applicants&#39; sound head matrix assembly  605  comprises a 4×2 sound head matrix. As a general matter, Applicants&#39; sound head matrix assembly comprises a Y×Z sound head matrix, wherein Y represents the number of transducers in a column, and wherein Z represents the number of columns, wherein Y is greater than or equal to 1, and less than or equal to about 10, and wherein Z is greater than or equal to 1 and less than or equal to about 6. 
         [0095]    For example in certain embodiments, Applicants&#39; hand-held ultrasonic device  610  comprises an 8×2 sound head matrix, such as the sound head matrix recited in  FIG. 4A . In certain embodiments, Applicants&#39; hand-held ultrasonic device  610  comprises a 4∴4 sound head matrix, such as the sound head matrix recited in  FIG. 5A . 
         [0096]    In the illustrated embodiment of  FIG. 6 , Applicants&#39; sound head matrix assembly is substantially flat. In other embodiments, Applicants&#39; sound head matrix assembly comprises (N) offset planar assemblies, wherein (N) is greater than or equal to 2 and less than or equal to about 6. 
         [0097]    For example, in certain embodiments, Applicants&#39; hand-held ultrasonic device  610  comprises offset sound head matrix assembly  401  ( FIGS. 2A ,  3 A,  4 A,  4 B) ), where that sound head matrix assembly comprises a Y×2 sound head matrix. In other embodiments, Applicants&#39; hand-held ultrasonic device  610  comprises offset sound head matrix assembly  402  ( FIG. 4C ), where that sound head matrix assembly comprises a Y×2 sound head matrix. In other embodiments, Applicants&#39; hand-held ultrasonic device  610  comprises offset sound head matrix assembly  501  ( FIGS. 5A ,  5 B), where that sound head matrix assembly comprises a Y×4 sound head matrix. In other embodiments, Applicants&#39; hand-held ultrasonic device  610  comprises offset sound head matrix assembly  502  ( FIG. 5C ), where that sound head matrix assembly comprises a Y×4 sound head matrix. 
         [0098]    Controller  620  is interconnected with hand-held device  610  by communication link  628 . In certain embodiments, communication link  628  is selected from the group which includes a serial interconnection, such as RS-232 or RS-422, an ethernet interconnection, a SCSI interconnection, a Fibre Channel interconnection, an ESCON interconnection, a FICON interconnection, a Local Area Network (LAN), a private Wide Area Network (WAN), a public wide area network, Storage Area Network (SAN), Transmission Control Protocol/Internet Protocol (TCP/IP), the Internet, and combinations thereof. 
         [0099]    Communication link  628  can be releaseably attached to coupling  630  disposed on housing  170 . Coupling  630  is interconnected with control bus  640 . Control bus  640  is interconnected to each transducer comprising Applicants&#39; sound head matrix assembly  610 . 
         [0100]    In certain embodiments, controller  620  provides control signals to hand-held device  610  wirelessly. In these wireless embodiments, communication link  628  comprises a first antenna coupled to controller  620  and coupling  630  comprises a second antenna coupled to communication bus  640 . 
         [0101]    Controller  620  includes processor  622 , memory  624 , and device microcode  626 . In certain embodiments, memory  624  comprises one or more nonvolatile memory devices. In certain embodiments, such nonvolatile memory is selected from the group which includes one or more EEPROMs (Electrically Erasable Programmable Read Only Memory), one or more flash PROMs (Programmable Read Only Memory), battery backup RAM, hard disk drive, combinations thereof, and the like. 
         [0102]    In certain embodiments, microcode  626  is stored in memory  624 . Device microcode  626  comprises instructions residing in memory, such as for example memory  624 , where those instructions are executed by processor  622  to implement the selected operational mode for the plurality of transducers comprising Applicants&#39; sound head matrix assembly. 
         [0103]    In certain embodiments, device microcode  626  comprises instructions residing in memory, such as for example memory  624 , where those instructions are executed by processor  622  to cause each of the plurality of therapeutic ultrasound transducers comprising Applicants&#39; sound head matrix assembly  605  to operate continuously. In other embodiments, device microcode  626  comprises instructions residing in memory, such as for example memory  624 , where those instructions are executed by processor  622  to cause each of the plurality of therapeutic ultrasound transducers comprising Applicants&#39; sound head matrix assembly  605  to operate discontinuously. 
         [0104]    As a general matter, such discontinuous operation modes include embodiments wherein each of the plurality of therapeutic ultrasound transducers comprising Applicants&#39; sound head matrix assembly  605  operates on a duty cycle from about 0.1 percent to 100 percent. In certain embodiments, such discontinuous operation modes include embodiments wherein each of the plurality of therapeutic ultrasound transducers comprising Applicants&#39; sound head matrix assembly  605  operates on a duty cycle selected from the group comprising a 20 percent duty cycle, a 40 percent duty cycle, a 60 percent duty cycle, and an 80 percent duty cycle. 
         [0105]    In certain of these discontinuous operational modes, each of the plurality of therapeutic ultrasound transducers comprising Applicants&#39; sound head matrix assembly  605  operates independently of any of the other transducer, i.e. each transducer is alternately turned on and off randomly. In other embodiments, an entire column of transducers operates at the same time, while transducers comprising other columns do not operate. In other embodiments, an entire row of transducers operates at the same time, while transducers comprising other rows do not operate. 
         [0106]    The following examples are presented to further illustrate to persons skilled in the art how to make and use Applicants&#39; invention, and to identify a presently preferred embodiment thereof. These examples are not intended as limitations, however, upon the scope of the invention. 
       EXAMPLE I 
       [0107]    For example and referring to  FIG. 5A , in certain embodiments a first column of therapeutic ultrasound transducers, which includes transducers  514 ,  515 ,  516 , and  517 , emit therapeutic ultrasound energy while a second column which includes transducers  524 ,  525 ,  526 ,  527 , and while a third column which includes transducers  534 ,  535 ,  536 ,  537 , and while a fourth column which includes transducers  544 ,  545 ,  546 , and  547 , do not emit therapeutic ultrasound energy. Thereafter, the transducers comprising the second column emit energy while the transducers in the first, third, and fourth columns do not. Applicants&#39; method includes embodiments wherein any pattern of sequential activation of columns of therapeutic ultrasound transducers. 
         [0108]    As a further example, in embodiments wherein Applicants&#39; sound head matrix comprises two or more columns, controller  620  (FIG.  6 )/ 720  ( FIGS. 7A ,  7 B)/ 805  ( FIGS. 8A ,  8 B), causes the ultrasound transducers arranged in a first column of that sound head matrix to emit ultrasound energy during a first time interval, and causes the ultrasound transducers in a second column of that sound head matrix to emit ultrasound energy during a second time interval, where the first time interval differs from the second time interval. Applicants&#39; method may define a treatment duration, and controller  620  (FIG.  6 )/ 720  ( FIGS. 7A ,  7 B)/ 805  ( FIGS. 8B ,  8 C),  895  ( FIG. 8E ), retrieves that pre-determined treatment duration, and alternates the first time interval and the second time interval throughout that treatment duration. 
       EXAMPLE II 
       [0109]    In another example, a first row of therapeutic ultrasound transducers, which includes transducers  514 ,  524 ,  534 , and  544 , emit therapeutic ultrasound energy while a second row which includes transducers  515 ,  525 ,  535 ,  534 , and while a third row which includes transducers  516 ,  526 ,  536 ,  545 , and while a fourth row which includes transducers  517 ,  527 ,  537 , and  547 , do not emit therapeutic ultrasound energy. Thereafter, the transducers comprising the second row emit energy while the transducers in the first, third, and fourth rows do not. Applicants&#39; method includes embodiments wherein any pattern of sequential activation of rows of therapeutic ultrasound transducers. 
         [0110]    As a further example, in embodiments wherein Applicants&#39; sound head matrix comprises two or more rows, controller  620  (FIG.  6 )/ 720  ( FIGS. 7A ,  7 B)/ 805  ( FIGS. 8B ,  8 C),  895  ( FIG. 8E ), causes the ultrasound transducers arranged in a first row of that sound head matrix to emit ultrasound energy during a first time interval, and causes the ultrasound transducers in a second row of that sound head matrix to emit ultrasound energy during a second time interval, where the first time interval differs from the second time interval. Applicants&#39; method may define a treatment duration, and controller  620  (FIG.  6 )/ 720  ( FIGS. 7A ,  7 B)/ 805  ( FIGS. 8B ,  8 C),  895  ( FIG. 8E ), retrieves that pre-determined treatment duration, and alternates the first time interval and the second time interval throughout that treatment duration. 
         [0111]    In certain embodiments, controller  620  comprises a computer, which in addition to memory  624  and microcode  624 , further includes one or more input devices, such as for example a key board, a mouse, a pointing device, and the like. In certain embodiments, that computer further includes one or more output devices, such as for example one or more monitors, one or more printers, and the like. 
         [0112]    In certain embodiments of Applicants&#39; apparatus, the external control circuitry of  FIG. 6 , i.e. controller  620 , is disposed within Applicants&#39; hand-held ultrasonic device. Referring to  FIG. 7A , hand-held device  710  includes the elements of device  610  in combination with controller  720 . For clarity of illustration,  FIG. 7  does not include power source  650 , power cable  660 , or power bus  605 . Controller  720  comprises processor  622 , memory  624 , and microcode  626 . 
         [0113]    Applicants&#39; hand-held ultrasonic device  710  includes controller  720  which is interconnected to each of a plurality of therapeutic ultrasound transducers  712 ,  713 ,  714 ,  715 ,  716 ,  717 ,  718 , and  719 , via communication links  732 ,  733 ,  734 ,  735 ,  736 ,  737 ,  738 , and  739 , respectively. 
         [0114]    For further clarity of illustration, the illustrated embodiment of  FIG. 7A  includes 4×2 sound head matrix assembly  705 . As a general matter, sound head matrix assembly  705  comprises a Y×Z sound head matrix, where that Y×Z sound head matrix is described above, and where that Y×Z sound head matrix may comprise a substantially flat assembly, or that Y×Z sound head matrix assembly may comprise (N) offset planar assemblies. In certain embodiments, controller  720  comprises an application specific integrated circuit, i.e. an “ASIC,” which integrates the functions of processor  622 , memory  624 , and microcode  626 . 
         [0115]    Referring now to  FIG. 7B , Applicants&#39; hand-held ultrasonic device  715  includes the elements of device  710  ( FIG. 7A ) in combination with integrated information input/output (“I/O”) device  750 . In the illustrated embodiment of  FIG. 7B , I/O device  750  includes a visual display device  760  and a plurality of input device/touch screens  771 ,  773 ,  775 ,  777 , and  779 . In certain embodiments, visual display device  760  comprises an LCD device. I/O device communicates with controller  720  via communication links  740  and  755 . 
         [0116]    In certain embodiments, Applicants&#39; hand-held ultrasonic device includes one or more diagnostic ultrasound emitters in combination with a plurality of therapeutic ultrasound emitters. Referring to  FIG. 8A , sound head matrix assembly  801  includes diagnostic ultrasound transceiver  810 , and a 2×3 sound head matrix comprising 6 therapeutic ultrasound emitters. Ultrasound transceiver  810  includes diagnostic ultrasound emitter  812  and receiving device  814 . By “diagnostic ultrasound emitter,” Applicants&#39; mean a device which is capable of emitting diagnostic ultrasound energy having a output power of between about 0.5 and about 1 milliwatt per cm 2  at a frequency of between about 7 and about 13 megahertz. Emitter  812  produces and emits ultrasound waves. Receiver  814  detects emissions reflected back to transceiver  810  by various underlying body tissues. Those reflected emissions are processed by the controller, such as for example controller  620  and/or controller  720 , and/or controller  805 , and that controller causes a visual display device, such as visual display device  760  to display an image of the tissue structure underlying the diagnostic ultrasound transceiver. 
         [0117]    Any of the various types of diagnostic ultrasound imaging devices may be employed in the practice of the invention, the particular type or model of the device not being critical to the method of the invention. Also suitable are devices designed for administering ultrasonic hyperthermia, such devices being described in U.S. Pat. Nos. 4,620,546, 4,658,828, and 4,586,512, the disclosures of each of which are hereby incorporated herein by reference in their entirety. Preferably, the device employs a resonant frequency (RF) spectral analyzer. 
         [0118]    Therapeutic ultrasound emitters  842 ,  844 , and  846 , are disposed on, or through, planar member  820 . Emitters  842 ,  844 , and  846 , in combination with planar member  820 , comprise planar assembly  860 . Therapeutic ultrasound emitters  852 ,  854 ,  856 , are disposed on, or through, planar member  830 . Emitters  852 ,  854 , and  856 , in combination with planar member  830 , comprise planar assembly  870 . 
         [0119]    Planar assembly  860  is continuously attached to planar assembly  870  at seam  825 . In certain embodiments, the dihedral angle formed by the intersection of planar assembly  860  and planar assembly  870  is 180 degrees, i.e. the angle Φ shown in  FIG. 8A  is zero. In other embodiments, planar assembly  860  is offset from planar assembly  870 , i.e. the angle Φ shown in  FIG. 8A  is greater than zero. 
         [0120]    Referring now to  FIG. 8B , Applicants&#39; hand-held device  800  includes sound head matrix assembly  801  in combination with controller  805  and housing  170 . Controller  805  includes a processor, such as processor  622 , memory, such as memory  624 , and device microcode, such as microcode  626 , to operate the plurality of therapeutic emitters  842 ,  844 ,  846 ,  852 ,  854 , and  856 , and microcode to operate diagnostic transceiver  810 . 
         [0121]    In certain embodiments, Applicants&#39; hand-held ultrasound device  800  includes an integral information input/output device. Referring now to  FIG. 8C , device  801  includes hand-held device  800  in combination with integrated I/O device  750 . Controller  805  communicates with I/O device  750  via communication links  804  and  755 . Diagnostic transceiver  810  is internally disposed within device  801  adjacent end  890 . In these embodiments, controller  805  includes a processor, such as processor  622 , memory, such as memory  624 , and device microcode, such as microcode  626 , to operate the plurality of therapeutic emitters  842 ,  844 ,  846 ,  852 ,  854 , and  856 , and microcode to operate diagnostic transceiver  810 , and microcode to operate visual display device  760 . 
         [0122]    Referring now to  FIG. 8D , device  801  can be removeably affixed to, for example, a patient&#39;s leg in order to direct ultrasound energy into the tissues of that leg. In certain embodiments, Applicants&#39; therapeutic method includes injecting microbubbles into a blood vessel distal to an occlusion in that vessel. Device  801  is positioned such that when the microbubbles approach the occasion site of the vessel, ultrasound energy produced by device  801  causes those bubbles to rupture, thereby removing all or part of the occlusion. 
         [0123]    When using device  801 , the diagnostic transceiver is first made operational. As those skilled in the art will appreciate, that diagnostic transceiver continuously emits relatively low power level ultrasound waves. The various body tissues differentially reflect a portion of those sound waves. The diagnostic transceiver detects those reflected signals. Controller  805  processes those reflected signals and generates an image signal. That image signal is provided to display device  760  which visually displays an image of the tissues and structures underlying device  801 . 
         [0124]    By monitoring display device  760 , the medical provider can determine when the injected microbubbles have reached the occlusion site. At that time, the medical provider than causes the plurality of therapeutic ultrasound emitters to produce ultrasound energy having a higher power level than the diagnostic power levels emitted by transceiver  810 . Those higher power ultrasound energy causes the microbubbles to rupture. After the flow of the injected microbubbles ceases, the medical provider then discontinues emission of the therapeutic ultrasound energy. 
         [0125]    In certain embodiments Applicants&#39; hand-held ultrasound device includes an “auto-detect” feature, wherein that devices monitors the reflected diagnostic signals, and automatically detects the arrival of the injected microbubbles at the occlusion site. When those injected microbubbles are detected, Applicants&#39; device automatically causes the plurality of therapeutic ultrasound devices to emit therapeutic ultrasound energy. When the flow of microbubbles ceases, Applicants&#39; device automatically causes the plurality of therapeutic ultrasound devices to stop emitting therapeutic ultrasound energy. 
         [0126]    Referring to  FIG. 8E , device  802  includes controller  895 . Controller  895  includes a processor and device microcode to operate diagnostic transceiver  810  and each of the plurality of therapeutic ultrasound emitters. Controller  895  further includes microcode which processes the reflected signals provided by transceiver  810 . Controller  895  is capable of detecting the arrival of the injected microbubbles at the occlusion site. Controller  895  causes one or more of therapeutic emitters to emit therapeutic ultrasound energy. When controller  895  detects the absence of microbubbles, controller  895  causes those therapeutic emitters to stop emitting sound waves. 
         [0127]      FIG. 9  summarizes Applicants&#39; method to use the various embodiments of Applicants&#39; hand-held ultrasonic device to treat an occlusion lodged in a blood vessel. In certain embodiments, the occluded vessel comprises an artery. In certain embodiments, the occluded vessel comprises a vein. In certain embodiments, the occluded vessel comprises an artery/vein disposed in a patient&#39;s leg. In certain embodiments, the occluded vessel comprises an artery/vein disposed in a patient&#39;s arm. In certain embodiments, the occluded vessel comprises an artery/vein disposed in a patient&#39;s myocardium. In certain embodiments, the occluded vessel comprises an artery/vein disposed within a patient&#39;s cranial cavity. 
         [0128]    In step  905 , the method provides an injectable microbubble formulation. U.S. Pat. Nos. 5,656,211 and 6,033,646 teach methods to form such a microbubble formulation, and are hereby incorporated by reference herein. U.S. Pat. No. 6,039,557 teaches an apparatus for preparing such a microbubble formulation, and is hereby incorporated by reference herein. 
         [0129]    In step  910 , the method determines the situs of the blood vessel occlusion. As those skilled in the art will appreciate, various methods exist to determine that situs. Step  910  includes identifying the occluded vessel. Step  910  further includes. identifying the location of the occlusion in that subject vessel. In certain embodiments, step  910  further includes determining the depth of the occluded vessel portion from the skin surface. In certain embodiments, step  910  further includes determining the width of the vessel at the occlusion. In certain embodiments, step  910  further includes determining the height of the vessel at the occlusion. 
         [0130]    Referring to  FIG. 10 , chart  1010  shows measurement data for various veins disposed in the leg of a human patient  1000 . Chart  1010  recites depth from surface data, vein width data, and vein height data. 
         [0131]    Referring to  FIG. 11 , chart  1110  shows measurement data for various veins disposed in the leg of a human patient  1100 . Chart  1110  recites depth from surface data, vein width data, and vein height data. 
         [0132]    Referring to  FIG. 12 , chart  1210  shows measurement data for various veins disposed in the leg of a human patient  1200 . Chart  1210  recites depth from surface data, vein width data, and vein height data. 
         [0133]    In step  915 , the method selects a therapeutic ultrasound emitting device and power level based upon the determinations of step  910 . Referring now to  FIG. 13 , vessel  1350  includes occlusion site  1360 . Using the determinations of step  910 , and estimating the error levels of those various determinations, the operator defines a target subcutaneous energy envelope  1310 . Energy envelope  1310  includes dimension  1340  along the Z direction, dimension  1320  along the X direction, and dimension  1330  along the Y direction. 
         [0134]    Having determined a target energy envelope, step  915  further includes selecting a sound head matrix that emits an actual ultrasound energy envelope that most closely corresponds to the desired target energy envelope. Step  915  further includes determining output power levels, and an emitter operating protocol, i.e. continuous or discontinuous operation.  FIG. 14A  shows a cross-sectional view of the ultrasound energy profile in the X/Z plane generated by a 2×Z offset sound head matrix  1410 . First emitter  1420  produces energy profile  1425 . Second emitter  1430  produces energy profile  1435 .  FIG. 14B  shows convergence point  1440  for the overlapping energy profiles for emitter  1420  and  1430 . 
         [0135]      FIG. 15A  shows a cross-sectional view of the ultrasound energy profile, in the X/Z plane, generated by a 3×Z offset sound head matrix  1510 . First emitter  1520  produces energy profile  1525 . Second emitter  1530  produces energy profile  1535 . Third emitter  1540  produces energy profile  1545 .  FIG. 15B  shows convergence point  1550  for the overlapping energy profiles for emitters  1520 ,  1530 , and  1540 . 
         [0136]      FIG. 16A  shows a cross-sectional view of the ultrasound energy profile, in the X/Z plane, generated by a 4×Z offset sound head matrix  1610 . First emitter  1620  produces energy profile  1625 . Second emitter  1630  produces energy profile  1635 . Third emitter  1640  produces energy profile  1645 . Fourth emitter  1650  produces energy profile  1655 .  FIG. 16B  shows convergence point  1660  for the overlapping energy profiles for emitters  1620 ,  1630 ,  1640 , and  1650 . 
         [0137]    Referring again to  FIG. 9 , in step  920  Applicants&#39; method positions the therapeutic ultrasound emitting device, selected in step  915 , over the occlusion site located in step  910 . Referring now to  FIG. 17 , Applicants&#39; hand-held ultrasound device  1701  includes a 2×8 offset sound head matrix assembly  1710  and housing  1760  ( FIG. 1C ), where housing  1760  is formed to include apertures  1720  and  1730  extending through a first side of that housing. Device  1701  further includes elastic straps  1740  and  1750 , where one end of those straps is attached to the second side of housing  1760  adjacent sound head matrix assembly  1710 . The distal end of elastic strap  1740  comprises tab  1745 . The distal end of elastic strap  1750  comprises tab  1755 . 
         [0138]    Device  1701  can be releaseably attached to the patient&#39;s extremity by advancing elastic straps  1740  and  1750  around that extremity, inserting tab  1745  into and through aperture  1720 , securing tab  1745 , inserting tab  1755  into and through aperture  1730 , and securing tab  1755 . In certain embodiments, tabs  1745  and  1755  are secured using hook and loop fasteners, i.e. VELCRO® fasteners. In other embodiments, tabs  1745  and  1755  are secured using buckle devices disposed on housing  1760 . 
         [0139]    Referring to  FIG. 18 , ultrasound coupling medium  1810  is positioned on skin surface  1820  over the occlusion site. Applicants&#39; hand-held ultrasound device  1701  is then place on top coupling medium  1810 . Device  1701  can then be secured in position using straps  1740  ( FIG. 17) and 1750  ( FIG. 17 ). In certain embodiments, the ultrasound coupling medium comprises carageenan. As those skilled in the art will appreciate, carageenan is a long chain polysacharide with a backbone of the sugar galactose. In other embodiments, the ultrasound coupling medium comprises xanthum gum. In other embodiments, the ultrasound coupling medium comprises alginic acid. As those skilled in the art will appreciate, alginic acid is a naturally occurring hydrophilic colloidal polysaccharide obtained from the various species of brown seaweed (Phaeophyceae), and comprises a linear copolymer consisting mainly of residues of b-1,4-linked D-mannuronic acid and a-1,4-linked L-glucuronic acid. In other embodiments, the ultrasound coupling medium comprises a silicon gel. 
         [0140]    Referring again to  FIG. 9 , after positioning the selected therapeutic ultrasound emitting device over the occlusion site in step  920 , Applicants&#39; method transitions to step  925  wherein the medical provider injects the microbubble formulation of step  905  into the subject vessel distal to the occlusion site. 
         [0141]    In step  930 , Applicants&#39; method determines if the ultrasound device selected in step  915  includes a diagnostic emitter. If Applicants&#39; method determines in step  930  that the selected hand-held ultrasound device includes a diagnostic ultrasound emitter, then Applicant&#39;s method transitions to step  955  wherein the method determines if the selected device includes an auto-detect function. If Applicants&#39; method determines in step  955  that the device selected in step  915  includes both a diagnostic ultrasound emitter and an auto-detect function, then Applicants&#39; method transitions from step  955  to step  960  wherein the operator initiates the auto-detect function. In embodiments wherein the selected device includes both a diagnostic ultrasound emitter and an auto-detect function, the operator need do no more than initiate the auto-detect function. The apparatus then automatically detects the arrival of the microbubbles at the occlusion site, automatically initiates the selected ultrasound emission program, automatically detects the absence of microbubbles at the occlusion site, and automatically discontinues ultrasound emissions. 
         [0142]    If Applicants&#39; method determines in step  955  that the selected device does not include an auto-detect function, then the method transitions from step  955  to step  965  wherein the operator determines if the selected device includes a display screen in combination with the diagnostic ultrasound emitter. If the selected device does include a display screen in combination with the diagnostic ultrasound emitter, then the method transitions to step  975  wherein the operator monitors the display device. 
         [0143]    In step  980 , the operator visually sees, using the display device, the presence of microbubbles at the occlusion site. Applicants&#39; method transitions from step  980  to step  985  wherein the operator causes the hand-held ultrasound device to provide therapeutic ultrasound energy to the occlusion site. In step  990 , the operator visually detects the absence of microbubbles at the occlusion site. Applicants&#39; method transitions from step  990  to step  950  wherein the operator discontinues ultrasound emissions. 
         [0144]    If the operator determines in step  965  that the selected hand-held ultrasound device includes a diagnostic ultrasound emitter but does not include a display screen, then the method transitions from step  965  to step  970  wherein the operator receives an indication that microbubbles are present at the occlusion site. In certain embodiments, the indication of step  970  comprises a visual alert, such as for example a flashing light. In certain embodiments, the indication of step  970  comprises a auditory alert. Applicants&#39; method transitions from step  970  to step  935  wherein the operator determines a treatment time interval. That treatment time interval comprises an estimate made by the operator of the time period in which microbubbles are likely to be present at the occlusion site. Applicants&#39; method transitions from step  935  to step  940  wherein the operator causes the selected device to emit therapeutic ultrasound energy. In certain embodiments, steps  935  and  940  are performed substantially synchronously. 
         [0145]    In step  945 , the operator determines if the treatment time interval selected in step  935  has expired. If the operator determines that the treatment time interval has not expired, then the method continues to provide therapeutic ultrasound energy to the occlusion site. Alternatively, if the operator determines in step  945  that the treatment time interval has expired, then the method transitions from step  945  to step  950  wherein the operator discontinues ultrasound emissions. 
         [0146]    In certain embodiments, individual steps recited in  FIG. 3A , and/or  FIG. 3B , and/or  FIG. 3C , may be combined, eliminated, or reordered. 
         [0147]    In certain embodiments, Applicants&#39; invention includes microcode, such as microcode  626 , where that microcode is executed by a controller, such as controller  620  (FIG.  6 )/ 720  ( FIGS. 7A ,  7 B)/ 805  ( FIGS. 8B ,  8 C),  895  ( FIG. 8E ), to perform one or more of steps  935 ,  940 ,  945 ,  950 ,  960 ,  980 ,  985 ,  990 , recited in  FIG. 9 . 
         [0148]    In other embodiments, Applicants&#39; invention includes instructions residing in any other computer program product, where those instructions are executed by a computer external to, or internal to, Applicants&#39; hand-held apparatus to perform steps one or more of steps  935 ,  940 ,  945 ,  950 ,  960 ,  980 ,  985 ,  990 , recited in  FIG. 9 . In either case, the microcode/instructions may be encoded in an information storage medium comprising, for example, a magnetic information storage medium, an optical information storage medium, an electronic information storage medium, and the like. By “electronic storage media,” Applicants mean, for example, a device such as a PROM, EPROM, EEPROM, Flash PROM, compactflash, smartmedia, and the like. 
         [0149]    While the preferred embodiments of the present invention have been illustrated in detail, it should be apparent that modifications and adaptations to those embodiments may occur to one skilled in the art without departing from the scope of the present invention.