Dual-frequency method for non-invasively treating a selected region of a living body

Abstract

The method and apparatus of the invention are directed to surgically non-invasively treating skeleto/muscular injuries or of diagnosing bone fractures, involving application of two components of ultrasonic energy, to an external surface of living tissue, wherein the two components are of different frequencies in the range between 10 kHz and 4 MHz, and wherein separate transducers, each uniquely supplied with an excitation signal at a different one of said two frequencies, are directionally disposed for acoustic propagation on the same directional axis.

What is claimed is:  
     
         1 . An apparatus to treat skeleto/muscular injuries within or below a body surface or to diagnose bone fractures, wherein the device comprises piezoelectric means to generate ultrasonic energy, said piezoelectric means comprising at least two generator means, one of which generator means is adapted to deliver energy at a relatively low frequency and generally along a longitudinal axis, the other of which generator means is adapted to deliver energy at a relatively high frequency and generally along said longitudinal axis, both of said frequencies being in the range between 10 KHz and 4 MHz, a relatively large body-application head associated with said first generator means, and a relatively small body-application head associated with said second generator means and carried by said relatively large application head.  
     
     
         2 . An apparatus as claimed in  claim 1 , wherein said one generator means provides energy at a frequency in the range between 10 and 110 kHz, advantageously 20 to 100 kHz, and optionally in the region of 45 kHz.  
     
     
         3 . An apparatus as claimed in  claim 2 , wherein said second generator means generates energy at a frequency in the range between 0.5 and 4 MHz, advantageously 0.5 to 3 MHz, and optionally in the region of 1 MHz.  
     
     
         4 . A dual-frequency body-applicator device, comprising first and second ultrasonic piezo-electric transducers on a single axis of longitudinal acoustic propagation, the first transducer including at one longitudinal end a generally cylindrically annular body-application head having a cylindrical bore, said first transducer being adapted for independent connection to a first source of relatively low-frequency acoustic-signal excitation, said second transducer being mounted in said bore and having at said longitudinal end a body-application head, said second transducer being adapted for independent connection to a second source of relatively high-frequency acoustic-signal excitation.  
     
     
         5 . A dual-frequency body-applicator device, comprising first and second ultrasonic piezo-electric transducers on a single axis of longitudinal acoustic propagation, the first transducer including at one longitudinal end a generally cylindrically annular body-application head having a cylindrical bore, said first transducer being adapted for independent connection to a first source of relatively low-frequency acoustic-signal excitation, said second transducer being mounted in said bore with at least some acoustic isolation from said first transducer and having at said longitudinal end a body-application head, said second transducer being adapted for independent connection to a second source of relatively high-frequency acoustic-signal excitation.  
     
     
         6 . The device of  claim 5 , in which the body-application longitudinal ends of said heads are concentrically adjacent in substantially the same geometric radial plane about said axis.  
     
     
         7 . The device of  claim 5 , in which the body-application end of said annular head is convexly contoured as a surface of revolution about said axis.  
     
     
         8 . The device of  claim 7 , in which the convex contour of said annular head is generally spherical.  
     
     
         9 . The device of  claim 8 , in which the body-application end of said second-transducer head is generally spherical and is centered on said axis.  
     
     
         10 . The device of  claim 9 , in which the body-application end of said second-transducer head is generally spherical but of spherical radius less than that of said annular head.  
     
     
         11 . The device of  claim 8 , in which the body-application end of said second-transducer head comprises a central convex generally spherical portion centered on said axis and an annular concave surface of revolution contiguous to said central convex generally spherical portion.  
     
     
         12 . The device of  claim 11 , in which said annular concave surface of revolution is based on a section profile wherein the convex-surface portion is based on a first substantially circular arc centered on said single axis, and in which the annular concave-surface portion is based on a substantially circular second arc of shorter(radius than said first arc and centered at radial offset from said single axis.  
     
     
         13 . The device of  claim 12 , in which the body-application end of said second-transducer head is characterized by a circumferentially continuous and smoothly faired transitional connecting region of inflexion between said convex and concave surface portions.  
     
     
         14 . The device of  claim 5 , in which the body-application head for said second transducer is generally cup-shaped, with a cylindrically annular skirt portion having an open tail end and integrally formed with a closed head-end portion, the cylindrical bore of said annular body-application head having a radially inward shoulder for axially positional referencing of the open end of said skirt portion, said head-end portion having a convex body-application outer surface and a flat inner surface, said second transducer having a flat radiating face in adhesively bonded relation to the flat inner surface of said closed head-end portion.  
     
     
         15 . The device of  claim 14 , in which an elastomeric O-ring is axially-interposed between coacting axially spaced confronting formations of said annular body-application head and of the body-application head for said second transducer, whereby said O-ring can provide at least some acoustic isolation of said head ends with respect to each other.  
     
     
         16 . The device of  claim 14 , in which a circumferentially continuous annular frustoconical portion of the body-application head for said second transducer head integrally and axially compliantly connects said skirt portion to said closed head-end portion, whereby said frustoconical portion can provide at least some acoustic isolation of said head ends with respect to each other.  
     
     
         17 . The device of  claim 14 , in which an annular member of elastomeric material is axially interposed between said shoulder and the open end of said skirt portion, whereby said annular member of elastomeric material can provide at least some acoustic isolation of said head ends with respect to each other.  
     
     
         18 . The device of  claim 14 , in which said skirt portion has running clearance with the bore of said generally cylindrically annular body member, and means including an elastomeric O-ring interposed between said bore and said skirt portion for radially stabilized positioning of said skirt portion with respect to said bore.  
     
     
         19 . The device of  claim 5 , (a) in which said annular body-application head includes a circumferentially continuous radially inwardly extending lip formation at said one longitudinal end of said bore, (b) in which said bore is internally threaded near the other longitudinal end thereof, (c) in which circumferentially continuous externally threaded means engaged to the bore threads defines a radially inward shoulder formation at axial offset from said lip formation, (d) in which the body-application head of said second transducer includes a cylindrically annular portion having running fit in said bore between said lip and shoulder formations, (e) a first annular elastomeric ring retained between said lip formation and the cylindrically annular portion of the second-transducer head, and (f) a second annular elastomeric ring retained between said shoulder formation and the cylindrically annular portion of the second-transducer head.  
     
     
         20 . The device of  claim 19 , in which each of said elastomeric rings is an O-ring.  
     
     
         21 . The device of  claim 1 , in which the relatively large body-application head is of a dense-polymer material selected from the group consisting of acetyl, polypropylene and polycarbonate.  
     
     
         22 . The device of  claim 1 , in which the relatively large body-application head is of a plastics material having a specific impedance (W) in closely matching relation to that of human soft tissue.  
     
     
         23 . A method of treating skeleto/muscular injuries or of diagnosing bone fractures, comprising applying to an external surface of the tissue at least two different sources of ultrasonic energy, each of said sources being applied independently and with symmetry about a single directional axis of propagation, and each of said sources being at a different frequency in the range between 10 kHz and 4 MHz.  
     
     
         24 . The method of  claim 23 , in which the source of greater frequency is adapted for central-area contact of the tissue surface, and in which the source of lesser frequency is adapted for annular-area contact with the tissue surface and in circumferentially surrounding relation with respect to said central-area contact.  
     
     
         25 . The method of  claim 23 , in which the lesser one of said frequencies is in the range 10 to 110 kHz, and in which the greater one of said frequencies is in the range 0.5 to 3 MHz.