PRESSURE-PULSE THERAPY APPARATUS FOR TREATMENT OF TISSUE

Abstract: Pressure-pulse apparatus (10) includes a dome-shaped reflector (12), defining an X axis passing through its center, and a point of origin O at its center. The reflector is formed of three concentric sections having different geometric shapes: A substantially parabolic center section (14), a substantially ellipsoid ring section (16), and a second substantially ellipsoid ring section (18).

Description: PRESSURE-PULSE THERAPY APPARATUS FOR TREATMENT OF TISSUE FIELD OF THE INVENTION The present invention relates generally to apparatus for pressure-pulse therapy. The present invention relates in particular to the generation of compound pressure pulses especially for orthopedic therapy. BACKGROUND OF THE INVENTION Pressure-pulse therapy, also known as shock-wave therapy, has many uses. It is used in lithotripsy as a non-invasive technique for pulverizing kidney stones and calculi in the bladder and urethra. It is also used for dissolving lipids in cells close to the skin and in the pelvic region. In particular, it has many uses in orthopedic medicine, for example: a. inducement of bone growth; b. joining of bone fracture; c. disintegration of calculi in fibers and joints; d. osteoporosis; e. pain relief in the cases of calcific tendinitis of the shoulder joint, tennis elbow, golf elbow, plantar fasciitis (with and without heel spur). US Patent 4620545 "Non-Invasive Destruction of Kidney Stones" to Shene et al., whose disclosure is incorporated herein by reference, describes a pressure-pulse therapy apparatus which includes an ellipsoidal reflector, having a first focal point within the reflector's dome and a second focal point outside the reflector's dome. A flexible diaphragm caps the reflector, and the region contained by the reflector and the diaphragm is filled with a liquid medium, for pulse propagation. A pulse source is located at the first focal point, within the medium. This configuration provides that a portion of a pulse originating from the source, at the first focal point, will impinge on the reflector, be reflected by it, and be brought into focus at the second focal point. The reflector is movable and can be positioned so that the second focal point coincides with a concretion within the body that is to be pulverized. Sonic aiming means are used to detect the concretion and to direct the positioning of the reflector. In general, pressure-pulse therapy is accompanied by an imaging means, such as the sonic aiming means of US Patent 4620545. The region for treatment is generally small, between 0.3 and 1.5 cm, and it is desirous to image the location in order for the therapy to be applied effectively. X-ray imaging may be used; however, with x-rays, the patient and the physician are exposed to radiation doses with each treatment. PCT patent publication PCT WO 93/14720, "Method and Apparatus Particularly Useful for Treating Osteoporosis," to Spector, whose disclosure is incorporated herein by reference, offers an alternative to the need for an imaging means. It has a generally parabolic reflector, which has a single focal point within the reflector's dome. A flexible diaphragm caps the reflector and the region contained by the reflector and the diaphragm is filled with a liquid medium, as in the previous patent. A pulse source is located at the focal point, within the liquid. This configuration provides that a portion of a pulse originating from the source, at the focal point, will impinge on the reflector, and be reflected by it, collimated. In other words, the reflected pulse will be a non-focusing wave, so focusing means are not essential. Pressure pulse therapy can thus be image free. However, with a collimated beam, some pressure pulse energy is lost, when compared with a beam that is focused at the region for treatment. It would be desirous to direct more of the pressure-pulse energy at the region for treatment, without being dependent on an imaging means. SUMMARY OF THE INVENTION An aspect of the invention relates to a therapeutic method for providing a compound pressure pulse, having at least two subordinate pressure pulses. Preferably, each subordinate pressure pulse impinges on a region for treatment of a tissue with different, predetermined, propagation characteristics. Preferably, the different, predetermined, propagation characteristics of the subordinate pressure pulses provide for a regional treatment of the tissue rather than treatment to a substantially specific point. Preferably, because of the regional nature of the treatment, it can be applied effectively without an imaging means. An aspect of the invention relates to therapeutic apparatus for generating from a primary pressure pulse a compound pressure pulse having at least two subordinate pressure pulses. Preferably, the apparatus includes a dome-shaped reflector formed of at least two concentric sections having different geometric shapes: a center section and at least one ring section. Preferably, the center section is substantially parabolic and has a single focal point, preferably within the reflector's dome. Preferably, the at least one ring section is substantially ellipsoidal and has proximal and distal focal points, with respect to the reflector. Preferably, the proximal focal point of the substantially ellipsoid ring section coincides with the focal point of the substantially parabolic center section. Preferably, a pressure-pulse source, which is substantially a point source, is located at the coincident focal point of the substantially parabolic center and the substantially ellipsoid ring, within the reflector's dome. This configuration provides that a single, radially expanding primary pressure pulse originating from the source will impinge on the reflector and be reflected by it as a compound pulse, having at least two subordinate pulses. The portion reflected from the substantially parabolic center section will be collimated, with a diameter substantially equal to the diameter of the center section, thus forming a first subordinate pulse. The portion reflected from the at least one substantially ellipsoid ring section will be directed toward the distal focal point of the substantially ellipsoid ring section, thus forming at least one additional subordinate pulse. Preferably, the diameter of the substantially parabolic center section, hence, the diameter of the collimated first subordinate pulse, is about the same as the cross-section of the region for treatment, or slightly larger, thus providing for a regional treatment of the tissue. Preferably, the distal focal point of the at least one substantially ellipsoid ring section is within the region for treatment. Therefore, the second subordinate pulse is directed there. This is an improvement over PCT WO 93/14720 where all the reflected pulse was collimated, even outside the cross-section of the region for treatment, so some of the reflected pulse energy was lost to the treatment. In a further preferred embodiment, the dome-shaped reflector includes a substantially parabolic center section, having a single focal point, preferably within the reflector's dome, and a plurality of substantially ellipsoid ring sections, each having proximal and distal focal points, with respect to the reflector. Preferably, the proximal focal points of the plurality of the substantially ellipsoid ring sections coincide with each other and with the single focal point of the substantially parabolic center section. Preferably, the distal focal point of each ellipsoid ring section is at a different distance from the reflector, but still within the region for treatment. Thus, the portion reflected from the substantially parabolic center section will be collimated, as before, forming a first subordinate pulse. The portions reflected from the plurality of substantially ellipsoid ring sections will be directed at their respective distal focal points, forming a plurality of additional subordinate pulses that impart their energy at different points within the region for treatment. This configuration, too, will provide for a regional treatment of the tissue. In a still further preferred embodiment, both the center section and the one or more concentric ring sections are substantially ellipsoid, having proximal focal points that substantially coincide and fall within the reflector's dome and distal focal points, at different distances from the reflector, but still within the region for treatment. This configuration will provides for a regional treatment of the tissue, as well. Alternatively or additionally, other functions or combinations of functions may be used for describing the curvatures of the center section and the one or more ring sections. Alternatively, the substantially point pressure-pulse source is located on a centerline defined by the reflector, but somewhat off the coincident focal point of the concentric sections of the reflector. This configuration provides that a single, radially expanding primary pressure pulse originating from the source will impinge on the reflector and be reflected by it as a somewhat diffused compound pulse. Preferably, the portion reflected from the substantially parabolic center section will be slightly convergent, or slightly divergent. Preferably, portions reflected from the one or more substantially ellipsoid sections will reach the region for treatment somewhat diffused and off focus, and in this manner too, will provide for a regional treatment of the tissue. Alternatively or additionally, the center section is generally, but not exactly, parabolic. Alternatively or additionally, the one or more ring sections, or the center and the one or more ring sections, are generally, but not exactly, ellipsoid. Preferably, the portion reflected from the generally parabolic center section will be slightly convergent, or slightly divergent. Preferably, portions reflected from the one or more substantially ellipsoid sections will reach the region for treatment somewhat diffused and off focus, further providing for a regional treatment of the tissue. There is thus provided, in accordance with a preferred embodiment of the invention, pressure-pulse therapy apparatus for generating from a primary pressure pulse, originating from a pressure source, a therapeutic compound pressure pulse having at least two subordinate pressure pulses and including: a dome-shaped reflector formed of at least two concentric sections, having different geometric shapes and including: a center section, having first reflective characteristics associated therewith and formed to reflect a primary pressure pulse propagating thereon, from a pressure source, so as to form a first subordinate pressure pulse; at least one ring section, having second reflective characteristics associated therewith and formed to reflect a primary pressure pulse propagating thereon, from the pressure source, so as to form at least one additional subordinate pressure pulse; and an open end; a flexible diaphragm which caps the open end; a fluid medium contained within the reflector and the diaphragm, for facilitating propagation of the pressure pulses; a centerline, being the center axis of the dome shaped reflector; and a pressure-pulse source, immersed in the medium, located between the reflector and the diaphragm, on the centerline, for generating primary pressure pulses that propagate in the medium and whose portions are reflected by the reflector to form compounds of subordinate pulses. Preferably, the pressure-pulse source is substantially a point source, located at a point P. Preferably, the center section is substantially parabolic and has a single focal point, at point P. Preferably, the at least one ring section is substantially ellipsoid and has proximal and distal focal points with respect to the reflector; wherein the focal point of the center section and the proximal focal point of the at least one ring section substantially coincide at point P. Alternatively, the at least one ring section includes a plurality of substantially ellipsoid ring sections, each having proximal and distal focal points with respect to the reflector; wherein the proximal focal points of the plurality of ring sections substantially coincide; and wherein the focal point of the center section and the proximal focal points of the plurality of ring sections substantially coincide, at point P. In another preferred embodiment of the invention, the center section and the at least one ring section are substantially ellipsoid, each having proximal and distal focal points with respect to the reflector; wherein the proximal focal point of the center section and the proximal focal point of the at least one ring section substantially coincide, at point P. In a still another preferred embodiment of the invention, the center section is generally parabolic and has a single focal zone, generally at point P, and the at least one ring section is generally ellipsoid and has proximal and distal focal zones with respect to the reflector; wherein the focal zone of the center section and the proximal focal zone of the at least one ring section generally coincide, generally at point P. In another preferred embodiment of the invention, the center section and the at least one ring section are generally ellipsoid, each having proximal and distal focal zones with respect to the reflector; wherein the proximal focal zone of the center section and the proximal focal zone of the at least one ring section generally coincide, generally at point P. In another preferred embodiment of the invention, the pressure-pulse source is located at a point P". Preferably, the pressure-pulse source is arranged for traveling along the centerline, so as to bring point P" to coincidence with point P, when desired; to bring point P" to the right of point P, when desired; and to bring point P" to the left of point P, when desired. Alternatively, the reflector is arranged for traveling along the centerline, so as to bring point P" to coincidence with point P, when desired; to bring point P" to the right of point P, when desired; and to bring point P" to the left of point P, when desired. Preferably, the pressure-pulse source is operable to generate primary pressure pulses in the range between 1000 and 6000 bars. Preferably, the therapeutic apparatus is operable to generate, from the primary pressure pulse, subordinate pressure pulses in the range between 5 and 600 bars. Preferably, the fluid medium is a liquid, such as water or oil. Preferably, the apparatus is arranged for traveling along at least one and preferably a plurality of axes, for positioning against a tissue surface of a body. Preferably, the apparatus is arranged for tilting along at least one and preferably a plurality of angular directions, for positioning against a tissue surface of a body. Preferably, the apparatus includes a support fixture for a portion of the body to be treated. There is thus also provided, in accordance with a preferred embodiment of the invention, a pressure-pulse therapy method for generating from a primary pressure pulse, originating from a substantially point pressure source, a therapeutic compound pressure pulse having at least two subordinate pressure pulses and including: generating a primary pressure pulse from the source; propagating the primary pressure pulse in a fluid medium; employing a reflector formed of at least two concentric sections having different geometric shapes and including: a center section, having first reflective characteristics associated therewith; and at least one ring section, having second reflective characteristics associated therewith; reflecting a first portion of the primary pressure pulse propagation by the center section, thus forming a first subordinate pressure pulse of the compound pulse; and reflecting at least one additional portion of the primary pressure pulse propagation by the at least one ring section, thus forming at least one additional subordinate pressure pulse of the compound pulse. Preferably, reflecting a first portion of the propagation includes reflecting the propagation in a substantially collimated manner. Alternatively, reflecting a first portion of the propagation includes reflecting the propagation in a generally collimated manner. Alternatively still, reflecting a first portion of the propagation includes reflecting the propagation as a substantially focusing propagation. Alternatively still, reflecting a first portion of the propagation includes reflecting the propagation as a generally focusing propagation. Preferably, reflecting at least one additional portion of the propagation includes reflecting the propagation as a substantially focusing propagation. Alternatively, reflecting at least one additional portion of the propagation includes reflecting the propagation as a generally focusing propagation. In another preferred embodiment, employing a reflector includes employing a reflector formed of a plurality of concentric sections, and reflecting at least one additional portion of the primary pressure pulse propagation includes reflecting a plurality of additional portions of the primary pressure pulse propagation by a plurality of ring sections, thus forming a plurality of subordinate pressure pulses. In a still another preferred embodiment of the invention, the method further includes varying the distance between the reflector and the substantially point source. In a preferred embodiment of the invention, the method further includes therapeutical ly applying the compound pressure pulse to a tissue of a body. Preferably, the tissue is human tissue. Alternatively, the tissue is an animal tissue. BRIEF DESCRIPTION OF THE DRAWINGS The present invention will be more clearly understood from the accompanying detailed description and drawings, in which same number designations are maintained throughout the figures for each element and in which: Fig. 1 is a schematic representation of pressure-pulse therapy apparatus which includes a reflector formed of three concentric sections: a substantially parabolic center section and two substantially ellipsoid ring sections, in accordance with a preferred embodiment of the invention; Fig. 2A is a schematic representation a parabola; Fig. 2B is a schematic representation ellipses; Fig. 3 is a schematic representation of the specific geometry of a reflector formed of three concentric sections: a substantially parabolic center section and two substantially ellipsoid ring sections, in accordance with a preferred embodiment of the invention; Fig. 4 is a schematic representation of a compound pulse formed of subordinate pulses, as a function of time, in accordance with a preferred embodiment of the invention; Fig. 5 is a schematic representation of pressure-pulse therapy apparatus which includes a reflector formed of two concentric sections: a generally, but not exactly, parabolic center section and a generally, but not exactly, ellipsoid ring section, in accordance with a preferred embodiment of the invention; Fig. 6 schematically illustrates pressure-pulse therapy apparatus which includes a dome-shaped reflector formed of two concentric sections having different geometric shapes, and a pressure-pulse source, located on the x-axis, somewhat displaced from the focal point of the concentric sections of the reflector; Fig. 7 is a schematic representation of therapeutic treatment applied to a foot, in accordance with a preferred embodiment of the invention; Fig. 8A is a pictorial representation of pressure-pulse therapy apparatus applying therapeutic treatment to a foot; Fig. 8B is a pictorial representation of pressure-pulse therapy apparatus applying therapeutic treatment to an elbow; Fig. 8C is a pictorial representation of pressure-pulse therapy apparatus applying therapeutic treatment to a back of a shoulder; and Fig. 8D is a pictorial representation of pressure-pulse therapy apparatus applying therapeutic treatment to a frontal shoulder. DETAILED DESCRD?TION OF PREFERRED EMBODIMENTS Reference is now made to Fig. 1, which schematically illustrates pressure-pulse therapy apparatus 10, in accordance with a preferred embodiment of the invention. Pressure-pulse apparatus 10 includes a dome-shaped reflector 12, defining an x-axis passing through its center, and a point of origin O at its center (vertex). The reflector is formed of three concentric sections having different geometric shapes: a substantially parabolic center section 14, a substantially ellipsoid ring section 16, and a second substantially ellipsoid ring section 18. In order to illustrate the implications of this particular geometry, reference is now made to Figs. 2A and 2B, for a basic review of the important features of a parabola and an ellipse, as they relate to the present invention. The following discussion is based on "Standard Mathematical Tables," Editor-in-Chief of Mathematics S.M. Selby, The Chemical Rubber Co. (CRC), eighteenth Edition, pp. 355-356. Fig. 2A schematically illustrates an x-y coordinate system with point of origin O, and a parabola, L, whose vertex, N coincides with point O, and whose mathematical expression is given by: 1. y 2 = ±4 P x. The focal point, F, of parabola L is at (P,0). Fig. 2B schematically illustrates the x-y coordinate system with point of origin O, and two ellipses, M and Ν. Generally, an ellipse has two vertices, Nl and V2, major and minor axes, a and b, and a center C. The mathematical expression describing an ellipse with a center located on the x-axis, at some point (h,0), is: 2 2 2 2 2. (x-h) / a + y /b = 1, wherein when center C coincides with point of origin O the mathematical expression of the 2 2 2 2 ellipse is given by x / a + y /b = 1. The ellipse has two focal points, FI and F2, and the distance from the center to either focal point is given by: , , , 2 , 2. 1/2 3. ±(a - b ) . Therefore, FI is at: 2 2 1/2 4. FI = h - (a - b ) , while F2 is at: 2 2 1/2 5. F2 = h + (a - b ) Reference is now also made to Fig. 3, which schematically illustrates the special geometry of reflector 12 of Fig. 1. Preferably, a center section, between point O and points A-A is a section of parabola L, with vertex, N, at point O and a curvature described by expression 1 above. The focal point of this section, F, is at (P,0), or, 6. F = P. Preferably, a first ring section, between points A-A and B-B, is a section of ellipse M, having a curvature described by the expression: 7. (x-hι)7 a! 2 + y7bl 2 = l- Thus, a first, or proximal focal point, with respect to the reflector is at: T . . , , 2 - 2,1/2 8. Fi l = hι - (ai - bi ) , and a second, or distal focal point, with respect to the reflector is at: 2 2 1/2 9. Fι2 = hι + (aι - bi ) In a similar manner, a second ring section, between points B-B and C-C, is a section of ellipse Ν, having a curvature is described by the expression: 10. (x- 2)7 a 2 2 + y7b 2 2 = l. Its proximal focal point, with respect to the reflector is at: 2 2 1/2 11. F 2 1 = h 2 - (a2 - b2 ) , and its distal focal point, with respect to the reflector is at: 2 2 1/2 12. F 2 2 = h 2 + (a 2 - b 2 ) A first condition of a preferred embodiment of the present invention, as described in Fig. 3, is that at points A-A, the y values of the center, parabolic section and of the first ellipsoid ring section are substantially the same, and that at points B-B, the y values of the first and the second ellipsoid ring sections are substantially the same. A second condition of a preferred embodiment of the present invention, as described in Fig. 3, is that the focal point of the center, parabolic section, F, and the proximal focal points of the ellipsoid ring sections F^l and F2I, coincide, or: 13. F = Fιl = F 2 l, and 2 2 1/2 2 2 1/2 14. P = hi - (ai - bi )" = h 2 - (ai - b 2 T . Where still additional ellipsoid ring sections are used, the two conditions are extended to the additional rings. When the center section is also ellipsoid, the proximal focal points of all the ellipsoid sections should coincide. Preferably, the distal focal points of the ellipsoid ring sections, F]2 and F22, are different from each other. 15. F 2 1 ≠ F 2 2, and, 16. hι + . ( /aι 2 - bi ) m ≠ h v. 2 - ( ta 2 2 - b . 2 2) , 1/2 , and similarly, for additional ellipsoid ring sections, when they are used. Reference is again made to Fig. 1, where in accordance with a preferred embodiment, the curvature of section 14 is substantially described by expression 1, the curvature of section 16 is substantially described by expression 7, and the curvature of section 18 is substantially described by expression 10. Preferably, the values of P, h , a\, bi, h 2 , a 2 , and b2 are selected in a manner that meets the conditions specified by expressions 13 - 16. Thus, focal point F of substantially parabolic center section 14 and proximal focal points Fχl and F2I of substantially ellipsoid ring sections 16 and 18 coincide at a point P, on the x axis, preferably inside dome-shaped reflector 12. Distal focal point F 2 1 of section 16 and a distal focal point F22 of section 18 are at different distances from reflector 12, on the x axis, preferably within a region for treatment 26 of body tissue. In some preferred embodiments, the parameters of sections 14, 16, and 18, namely, P, a l. D l. h 2 , a 2' anc * ^2 are selected in a manner that provides for each first derivative at points A, B, and C, to have a single value, when calculated from the left and when calculated from the right. In this way, pressure losses due to points of discontinuities will be reduced. In some preferred embodiments, h = a\, and substantially ellipsoid ring section 16 is constructed as if its first vertex were at point of origin O. Alternatively or additionally, I12 = a 2 . In some preferred embodiment of the invention, sample values for the aforementioned parameters are as follows, P = 30; hi = 30; ai = 65; bi = 25; h2 = 35; a 2 = 70 b 2 = 27. A pressure-pulse source 24 is located at point P. Source 24 and reflector 12 are arranged in a fluid medium 20, preferably a liquid, such as an aqueous solution, water or oil, in which the pressure pulses propagate. A flexible diaphragm 22 essentially caps dome-shaped reflector 12 and contains fluid medium 20 within. When conducting therapeutic treatment, flexible diaphragm 22 of apparatus 10 is pressed against region for treatment 26, so that pressure pulses propagate through diaphragm 22 to region for treatment 26. Preferably, source 24 is substantially a point source. Alternatively, source 24 is generally a point source. A power supply unit 28, preferably located outside medium 20, powers source 24, with wires 29 connecting power supply unit 28 to source 24. The configuration of Fig 1 provides for a radially expanding primary pulse 30, originating from substantially point source 24, to form a compound of subordinate pulses, as follows: i. a first subordinate pulse 32, being a substantially collimated pulse, reflected from substantially parabolic center section 14; ii. a second subordinate pulse 34, being a substantially focusing pulse, reflected from substantially ellipsoid ring section 16, toward distal focal point Fι2, preferably, within region for treatment 26; and iii. a third subordinate pulse 36, being a substantially focusing pulse, reflected from substantially ellipsoid ring section 18, toward distal focal point F 2 2, preferably, within region for treatment 26. Reference is now made to Fig. 4, which schematically illustrates the effect of primary pressure pulse 30 on region for treatment 26, as a function of time. A portion of radially expanding primary pulse 30 will be the first to impinge on region for treatment 26. However, because of the radial nature of the expansion, its amplitude will be relatively low. Subordinate pulses 32, 34, and 36, reflected from reflector 12, will impinge on region for treatment 26 a little later, generally at different times, since the paths are different for each subordinate pulse. Radially expanding portion of primary pressure pulse 30 and collimated first subordinate pulse 32 inherently provide for regional treatment of the tissue. The combined effect of second subordinate pulse 34 and third subordinate pulse 36, each being directed at a different focal point within region for treatment 26, enhances the regional effect of the treatment. In some preferred embodiments, only one substantially ellipsoid ring section, such as substantially ellipsoid ring section 16 is used, and the compound pulse that is formed has only three subordinate pulses. Alternatively, more than two substantially ellipsoid ring sections are used, and the compound pulse that is formed has more that four subordinate pulses. Reference is now made to Fig. 5, which schematically illustrates pressure-pulse therapy apparatus 100, in accordance with another preferred embodiment of the invention. Pressure-pulse therapy apparatus 100 includes a generally, but not exactly, parabolic center section 114, having a focal zone P'. Focal zone P' can be determined as follows: a collimated propagation impinging on generally parabolic center section 114 will be directed as focal zone P', thus defining focal zone P'. Preferably, focal zone P' is within the reflector's dome. Pressure-pulse therapy apparatus 100 further includes a generally, but not exactly, ellipsoid ring section 116, having a proximal focal zone FI ', which generally coincides with P', and a distal focal zone F2', preferably within region for treatment 26, in accordance with another preferred embodiment of the invention. Focal zone F2' can be determined as follow: a radially expanding propagation, originating from a point source at a point in the center of focal zone FI' and impinging on generally ellipsoid ring section 116, will be directed at focal zone F2', thus defining focal zone F2'. Similarly, focal zone FT can be determined as follow: a radially expanding propagation, originating from a point source at a point in the center of focal zone F2' and impinging on generally ellipsoid ring section 116, will be directed at focal zone FT, thus defining focal zone FT. Preferably, when a portion of primary pulse 30 impinges on generally parabolic center 114, it is reflected as a slightly convergent or slightly divergent first subordinate pulse 132. Preferably, when a portion of primary pulse 30 impinges on generally ellipsoid ring 116, it is reflected as a poorly focusing second subordinate pulse 134, generally directed at zone F2', preferably within region for treatment 26, rather than at a point such as F 2 of Fig. 1. In this manner, regional treatment is rendered also by subordinate pulse 134 reflected from a single, generally ellipsoid ring section. Reference is now made to Fig. 6, which schematically illustrates pressure-pulse therapy apparatus 200, in accordance with still another preferred embodiment of the invention. Pressure-pulse therapy apparatus 200 includes a dome-shaped reflector 212 formed of two concentric sections having different geometric shapes: a substantially parabolic center section 214 having a focal point F at point P, and a substantially ellipsoid ring section 216 having a proximal focal point FI, at point P, and a distal focal point F2. Pressure-pulse source 24 is located on the x-axis, at point P", somewhat farther away from reflector 12 than point P. This configuration also provides that a radially expanding primary pulse 30, originating from pressure-pulse source 24 will impinge on reflector 12 and be reflected by it as a compound pulse of somewhat diffused subordinate pulses: A first subordinate pulse 232 which will be slightly convergent, and a poorly focusing second subordinate pulse 234, generally directed at a zone F2", preferably within region for treatment 26. This configuration, too, provides for a regional treatment of the tissue. Alternatively, point P", at which pressure-pulse source 24 is located, is closer to reflector 12 than point P. Alternatively or additionally, pressure-pulse source 24 is arranged for traveling along the x-axis, so as to bring point P" to coincidence with point P, when desired, to bring point P" to the right of point P, when desired, and to bring point P" to the left of point P, when desired. Alternatively or additionally, reflector 212 is arranged for traveling along the x-axis, so as to bring point P" to coincidence with point P, when desired, to bring point P" to the right of point P, when desired, and to bring point P" to the left of point P, when desired. Preferably, traveling along the x-axis includes traveling on a rail. Alternatively, travelling along the x-axis includes travelling on a threaded rod. In some preferred embodiments, center region 14 is also substantially ellipsoid. In some preferred embodiments, functions other than a parabola and an ellipse and different combinations of functions may be used for the curvature of concentric sections of the reflector. For example, a linear function may be used. Reference is now made to Fig. 7, which schematically illustrates the application of therapeutic treatment by apparatus 10 to a foot 44, with diaphragm 22 pressing against surface tissue of foot 44, in accordance with a preferred embodiment of the invention. Reference is now made to Figs. 8A-8D, which are pictorial representations of apparatus 10 applying therapeutic treatment to different bodily parts, in accordance with some preferred embodiments of the invention. Fig. 8A illustrates a situation wherein apparatus 10 applies therapeutic treatment to foot 44. A support fixture 40, such as a foot rest, is used to facilitate the positioning of foot 44 against apparatus 10. Preferably, support fixture 40 is adjustable to support different parts of the body. Preferably, support fixture 40 is removable, so apparatus 10 can be pressed directly against a body when a patient is standing or lying prone. Alternatively, support fixture 40 can be folded in. Fig. 8B illustrates a situation wherein apparatus 10 applies therapeutic treatment to an elbow 42, supported by support fixture 40, preferably adjusted for an elbow. Fig. 8C illustrates a situation wherein apparatus 10 applies therapeutic treatment to a back of a shoulder 46. Preferably, support fixture 40 has been removed or folded in, and apparatus 10 is pressed directly against back of shoulder 46. Preferably, apparatus 10 is arranged for traveling along at least one and preferably a plurality of axes, on means of travel 50, such as a gantry or a below. Preferably, apparatus 10 is also arranged for tilting in at least one and preferably a plurality of angular directions, also by means of travel 50. Preferably, means of travel 50 provide for easy positioning of apparatus 10 against a body. Fig. 8D illustrates a situation wherein apparatus 10 applies therapeutic treatment to a frontal shoulder 48, wherein apparatus 10 is pressed directly against frontal shoulder 48. In some preferred embodiments, the therapeutic apparatus is used with no accompanying imaging means, since the treatment is regional in nature. Alternatively, x-ray or sonic means are used. Alternatively, another form of imaging means is used. Preferably, pressure-pulse source 24 is operable to generate primary pressure pulses in the range between 1000 and 6000 bars. Preferably, the therapeutic apparatus is operable to generate, from the primary pressure pulse, subordinate pressure pulses in the range between 5 and 600 bars. Preferably, source 24 is a spark gap source described in US Patent 3,442,531 to MOR, 1976, whose disclosure is incorporated herein by reference. Alternatively, any spark plug source, or a piezoelectric source or another known source, preferably, a point-source may be used. Preferably, the reflector is formed of a material of good acoustic reflection properties, for example, stainless steel, brass or aluminum. Alternatively, another material may be used. Preferably, the reflector is supported by a mechanical means. It will be appreciated by persons skilled in the art that the scope of the present invention is not limited by what has been specifically shown and described hereinabove, merely by way of example. Rather, the scope of the invention is limited solely by the claims, which follow.

Claims: CLAIMS 1. A dome-shaped reflector for generating from a primary pressure pulse, originating from a pressure source, a therapeutic compound pressure pulse having at least two subordinate pressure pulses, wherein said reflector is formed of at least two concentric sections having different geometric shapes and including: a center section, having first reflective characteristics associated therewith and formed to reflect a primary pressure pulse propagating thereon, from a pressure source, so as to form a first subordinate pressure pulse of the compound pulse; and at least one ring section, having second reflective characteristics associated therewith and formed to reflect a primary pressure pulse propagating thereon, from said pressure source, so as to form at least one additional subordinate pressure pulse of the compound pulse. 2. A reflector according to claim 1, wherein said center section is substantially parabolic and has a single focal point. 3. A reflector according to claim 2, wherein said at least one ring section is substantially ellipsoid and has proximal and distal focal points with respect to said reflector; and wherein said focal point of said center section and said proximal focal point of said at least one ring section substantially coincide. 4. A reflector according to claim 3, wherein said at least one ring section includes a plurality of substantially ellipsoid ring sections, each having proximal and distal focaj points with respect to said reflector; wherein said proximal focal points of said plurality of ring sections substantially coincide; and wherein said focal point of said center section and said proximal focal points of said plurality of ring sections substantially coincide. 5. A reflector according to claim 1, wherein said center section and said at least one ring section are substantially ellipsoid, each having proximal and distal focal points with respect to said reflector; and wherein said proximal focal point of said center section and said proximal focal point of said at least one ring section substantially coincide. 6. A reflector according to claim 5, wherein said at least one ring section includes a plurality of substantially ellipsoid ring sections, each having proximal and distal focal points with respect to said reflector; wherein said proximal focal points of said plurality of ring sections substantially coincide; and wherein said proximal focal point of said center section and said proximal focal points of said plurality of ring sections substantially coincide. 7. A reflector according to claim 1, wherein said center section is generally parabolic and has a single focal zone. 8. A reflector according to claim 7, wherein said at least one ring section is generally ellipsoid and has proximal and distal focal zones with respect to said reflector; and wherein said focal zone of said center section and said proximal focal zone of said at least one ring section generally coincide. 9. A reflector according to claim 8, wherein said at least one ring section includes a plurality of generally ellipsoid ring sections, each having proximal and distal focal zones with respect to said reflector; wherein said proximal focal zones of said plurality of ring sections generally coincide; and wherein said focal zone of said center section and said proximal focal zones of said plurality of ring sections generally coincide. 10. A reflector according to claim 1, wherein said center section and said at least one ring section are generally ellipsoid, each having proximal and distal focal zones with respect to said reflector; and wherein said proximal focal zone of said center section and said proximal focal zone of said at least one ring section generally coincide. 11. A reflector according to claim 10, wherein said at least one ring section includes a plurality of generally ellipsoid ring sections, each having proximal and distal focal zones with respect to said reflector; wherein said proximal focal zones of said plurality of ring sections generally coincide; and wherein said proximal focal zone of said center section and said proximal focal zones of said plurality of ring sections generally coincide. 12. Pressure-pulse therapy apparatus for generating from a primary pressure pulse, originating from a pressure source, a therapeutic compound pressure pulse having at least two subordinate pressure pulses and including: a dome-shaped reflector formed of at least two concentric sections having different geometric shapes and including: a center section, having first reflective characteristics associated therewith and formed to reflect a primary pressure pulse propagating thereon, from a pressure source, so as to form a first subordinate pressure pulse; at least one ring section, having second reflective characteristics associated therewith and formed to reflect a primary pressure pulse propagating thereon, from the pressure source, so as to form at least one additional subordinate pressure pulse; a centerline; and an open end; a flexible diaphragm which caps said open end; a fluid medium contained within said reflector and said diaphragm, for facilitating propagation of the pressure pulses; and a pressure-pulse source, immersed in said medium, located between said reflector and said diaphragm, on said centerline, for generating primary pressure pulses that propagate in said medium and whose portions are reflected by said reflector to form compounds of subordinate pulses. 13. Apparatus according to claim 12, wherein said pressure-pulse source is substantially a point source. 14. Apparatus according to claim 13, wherein said pressure-pulse source is located at a point P. 15. Apparatus according to claim 14, wherein said center section is substantially parabolic and has a single focal point, at said point P. 16. Apparatus according to claim 15, wherein said at least one ring section is substantially ellipsoid and has proximal and distal focal points with respect to said reflector; and wherein said focal point of said center section and said proximal focal point of said at least one ring section substantially coincide at said point P. 17. Apparatus according to claim 16, wherein said at least one ring section includes a plurality of substantially ellipsoid ring sections, each having proximal and distal focal points with respect to said reflector; wherein said proximal focal points of said plurality of ring sections substantially coincide; and wherein said focal point of said center section and said proximal focal points of said plurality of ring sections substantially coincide, at said point P. 18. Apparatus according to claim 14, wherein said center section and said at least one ring section are substantially ellipsoid, each having proximal and distal focal points with respect to said reflector; and wherein said proximal focal point of said center section and said proximal focal point of said at least one ring section substantially coincide, at said point P. 19. Apparatus according to claim 18, wherein said at least one ring section includes a plurality of substantially ellipsoid ring sections, each having proximal and distal focal points with respect to said reflector; wherein said proximal focal points of said plurality of ring sections substantially coincide; and wherein said proximal focal point of said center section and said proximal focal points of said plurality of ring sections substantially coincide, at said point P. 20. Apparatus according to claim 14, wherein said center section is generally parabolic and has a single focal zone, generally at said point P. 21. Apparatus according to claim 20, wherein said at least one ring section is generally ellipsoid and has proximal and distal focal zones with respect to said reflector; and wherein said focal zone of said center section and said proximal focal zone of said at least one ring section generally coincide, generally at said point P. 22. Apparatus according to claim 21, wherein said at least one ring section includes a plurality of generally ellipsoid ring sections, each having proximal and distal focal zones with respect to said reflector; wherein said proximal focal zones of said plurality of ring sections generally coincide; and wherein said focal zone of said center section and said proximal focal zones of said plurality of ring sections generally coincide, generally at said point P. 23. Apparatus according to claim 14, wherein said center section and said at least one ring section are generally ellipsoid, each having proximal and distal focal zones with respect to said reflector; and wherein said proximal focal zone of said center section and said proximal focal zone of said at least one ring section generally coincide, generally at said point P. 24. Apparatus according to claim 23, wherein said at least one ring section includes a plurality of generally ellipsoid ring sections, each having proximal and distal focal zones with respect to said reflector; wherein said proximal focal zones of said plurality of ring sections generally coincide; and wherein said proximal focal zone of said center section and said proximal focal zones of said plurality of ring sections generally coincide, generally at said point P. 25. Apparatus according to claim 13, wherein said pressure-pulse source is located at a point P". 26. Apparatus according to claim 25, wherein any of said pressure-pulse source and said reflector are arranged for traveling along said centerline, so as to bring said point P" to coincidence with a point P, when desired; to bring said point P" to the right of said point P, when desired; and to bring said point P" to the left of said point P, when desired. 27. Apparatus according to claim 26, wherein said center section is substantially parabolic and has a single focal point, at said point P. 28. Apparatus according to claim 27, wherein said at least one ring section is substantially ellipsoid and has proximal and distal focal points with respect to said reflector; and wherein said focal point of said center section and said proximal focal point of said at least one ring section substantially coincide at said point P. 29. Apparatus according to claim 28, wherein said at least one ring section includes a plurality of substantially ellipsoid ring sections, each having proximal and distal focal points with respect to said reflector; wherein said proximal focal points of said plurality of ring sections substantially coincide; and wherein said focal point of said center section and said proximal focal points of said plurality of ring sections substantially coincide, at said point P. 30. Apparatus according to claim 26, wherein said center section and said at least one ring section are substantially ellipsoid, each having proximal and distal focal points with respect to said reflector; and wherein said proximal focal point of said center section and said proximal focal point of said at least one ring section substantially coincide, at said point P. 31. Apparatus according to claim 30, wherein said at least one ring section includes a plurality of substantially ellipsoid ring sections, each having proximal and distal focal points with respect to said reflector; wherein said proximal focal points of said plurality of ring sections substantially coincide; and said proximal focal point of said center section and said proximal focal points of said plurality of ring sections substantially coincide, at said point P. 32. Apparatus according to claim 12, wherein said pressure-pulse is operable to generate primary pressure pulses in the range between 1000 and 6000 bars. 33. Apparatus according to claim 32, wherein said apparatus is operable to generate, from the primary pressure pulse, subordinate pressure pulses in the range between 5 and 600 bars. 34. Apparatus according to claim 12, wherein said apparatus is arranged for traveling along at least one axis, for positioning against a tissue surface of a body. 35. Apparatus according to claim 34, wherein said apparatus is arranged for traveling along a plurality of axes, for positioning against a tissue surface of a body. 36. Apparatus according to claim 12, wherein said apparatus is arranged for tilting along at least one angular direction, for positioning against a tissue surface of a body. 37. Apparatus according to claim 36, wherein said apparatus is arranged for tilting along a plurality of angular directions, for positioning against a tissue surface of a body. 38. Apparatus according to claim 12 and including a support fixture for a portion of the body to be treated. 39. A pressure-pulse therapy method for generating from a primary pressure pulse, originating from a substantially point pressure source, a therapeutic compound pressure pulse having at least two subordinate pressure pulses and including: generating a primary pressure pulse from said source; propagating of the primary pressure pulse in a fluid medium; employing a reflector formed of at least two concentric sections having different geometirc shapes and including: a center section, having first reflective characteristics associated therewith; and at least one ring section, having second reflective characteristics associated; reflecting a first portion of the primary pressure pulse propagation by said center section, thus forming a first subordinate pressure pulse of the compound pulse; and reflecting at least one additional portion of the primary pressure pulse propagation by said at least one ring section, thus forming at least one additional subordinate pressure pulse of the compound pulse. 40. A method according to claim 39, wherein reflecting a first portion of the propagation includes reflecting the propagation in a substantially collimated manner. 41. A method according to claim 39, wherein reflecting a first portion of the propagation includes reflecting the propagation in a generally collimated manner. 42. A method according to claim 39, wherein reflecting a first portion of the propagation includes reflecting the propagation as a substantially focusing propagation. 43. A method according to claim 39, wherein reflecting a first portion of the propagation includes reflecting the propagation as a generally focusing propagation. 44. A method according to claim 39, wherein reflecting at least one additional portion of the propagation includes reflecting the propagation as a substantially focusing propagation. 45. A method according to claim 39, wherein reflecting at least one additional portion of the propagation includes reflecting the propagation as a generally focusing propagation. 46. A method according to claim 39, wherein employing a reflector includes employing a reflector formed of a plurality of concentric sections that includes: a center section, having first reflective characteristics associated therewith; and a plurality of ring sections, having predetermined reflective characteristics associated therewith; and wherein reflecting at least one additional portion of the primary pressure pulse propagation includes reflecting a plurality of additional portions of the primary pressure pulse propagation by a plurality of ring sections, thus forming a plurality of subordinate pressure pulses. 47. A method according to claim 39, and further including varying the distance between said reflector and said substantially point source. 48. A method according to claim 39, and further including therapeutically applying the compound pressure pulse to a tissue of a body. 49. A method according to claim 48, wherein the tissue is human tissue.

Inventors: SPECTOR AVNER, SPECTOR, AVNER
Applicants: MEDISPEC LTD, SPECTOR AVNER, MEDISPEC LTD., SPECTOR, AVNER
Application year: 2000
Main classification: A61N7
IPC codes: A61B17, A61N7