METHOD AND DEVICES FOR TISSUE EXPANSION

Abstract

A device for maintaining or achieving soft tissue expansion applicable to any body region already temporarily expanded including: an adhesive element deformable and capable of adapting to the shape of this body region, and which can then itself become mechanically rigid enough to resist tendency of the expanded tissue to recoil or to which a second material can be applied to form a stent adapted to the shape of the body area to provide the necessary structural rigidity to prevent recoil of the expansion and thereby induce its retention of its expanded shape after the stent is removed.

Claims

1-43. (canceled)

44. A passive stent for retaining a patient's enlarged body region in an expanded state comprising: a single layer configured to transition between a first adhesion mode and a second retaining mode upon exposure to one or more stimuli, wherein the layer is configured to adhere and substantially conform to the external surface of the patient's enlarged body region when in the first adhesion mode, and wherein the layer is configured to maintain the patient's enlarged body region in the expanded state when in the second retaining mode.

45. The passive stent of claim 44, wherein the enlarged body region is a breast.

46. The passive stent of claim 44, wherein the layer decreases in flexibility when transitioning from the first adhesion mode to the second retaining mode.

47. The passive stent of claim 46, wherein the layer is semi-rigid in the second retaining mode.

48. The passive stent of claim 46, wherein the layer is rigid in the second retaining mode.

49. The passive stent of claim 44, wherein the adhesion occurs through surface tension.

50. The passive stent of claim 44, wherein the one or more stimuli is air, water, temperature, UV radiation, a catalyst, or a combination thereof.

51. The passive stent of claim 44, wherein the layer comprises a hydrogel, a hydrocolloid, a polyurethane, a silicone, or a pressure-sensitive adhesive.

52. The passive stent of claim 44, wherein the layer comprises a curable polymer.

53. The passive stent of claim 52, wherein the curable polymer is a thermoplastic polyurethane, a natural polymer, a synthetic polymer, an acrylic material, a plaster of Paris, or a silicone.

54. The passive stent of claim 44, wherein the layer comprises a biocompatible material.

55. The passive stent of claim 44, wherein the layer is a spray, a putty, a painted liquid or a soft rubber.

56. A passive stent for molding a patient's enlarged breast in an expanded state comprising: a single layer comprising a biocompatible cyanoacrylate material and configured to transition between a first adhesion mode and a second retaining mode upon exposure to one or more stimuli, wherein the layer is configured to adhere and substantially conform to the external surface of the patient's enlarged breast when in the first adhesion mode, and wherein the layer is configured to maintain the patient's enlarged breast in the expanded state when in the second retaining mode.

57. The passive stent of claim 56, wherein the layer decreases in flexibility when transitioning from the first adhesion mode to the second retaining mode.

58. The passive stent of claim 57, wherein the layer is semi-rigid in the second retaining mode.

59. The passive stent of claim 57, wherein the layer is rigid in the second retaining mode.

60. The passive stent of claim 56, wherein the adhesion occurs through surface tension.

61. The passive stent of claim 56, wherein the one or more stimuli is air, water, temperature, UV radiation, a catalyst, or a combination thereof.

62. A passive stent for retaining a patient's enlarged body region in an expanded state comprising: a single layer having both adhesive and structural properties, wherein the layer is configured to adhere and substantially conform to an external surface of the patient's enlarged body region, and wherein the layer is configured to maintain the patient's enlarged body region in the expanded state upon adhesion to the external surface.

63. The passive stent of claim 62, wherein the enlarged body region is a breast.

64. The passive stent of claim 62, wherein the layer decreases in flexibility upon adhesion to the external surface.

65. The passive stent of claim 64, wherein the layer is semi-rigid upon adhesion to the external surface.

66. The passive stent of claim 64, wherein the layer is rigid upon adhesion to the external surface.

67. The passive stent of claim 62, wherein the adhesion occurs through surface tension.

68. The passive stent of claim 62, wherein the layer comprises a hydrogel, a hydrocolloid, a polyurethane, a silicone, or a pressure-sensitive adhesive.

69. The passive stent of claim 62, wherein the layer comprises a curable polymer.

70. The passive stent of claim 69, wherein the curable polymer is a thermoplastic polyurethane, a natural polymer, a synthetic polymer, an acrylic material, a plaster of Paris, or a silicone.

71. The passive stent of claim 62, wherein the single layer comprises a biocompatible material.

72. The passive stent of claim 62, wherein the layer is a spray, a putty, a painted liquid, or a soft rubber.

73. A passive stent for molding a patient's body region comprising: a single layer having both adhesive and structural properties, wherein the layer is configured to adhere and substantially conform to an external surface of the patient's body, and wherein the layer is configured to maintain the external surface of the patient's body in an expanded state upon adhesion to the external surface.

74. The passive stent of claim 73, wherein the layer decreases in flexibility upon adhesion to the external surface.

75. The passive stent of claim 74, wherein the layer is semi-rigid upon adhesion to the external surface.

76. The passive stent of claim 74, wherein the layer is rigid upon adhesion to the external surface.

77. The passive stent of claim 73, wherein the one or more stimuli is air, water, temperature, UV radiation, a catalyst, or a combination thereof.

78. The passive stent of claim 73, wherein the layer comprises a curable polymer.

79. The passive stent of claim 78, wherein the curable polymer is a thermoplastic polyurethane, a natural polymer, a synthetic polymer, an acrylic material, a plaster of Paris, or a silicone.

80. The passive stent of claim 73, wherein the layer comprises a biocompatible material.

81. The passive stent of claim 73, wherein the layer is a spray, a putty, a painted liquid, or a soft rubber.

82. The passive stent of claim 73, wherein the adhesion occurs through surface tension.

83. The passive stent of claim 73, wherein the enlarged body region is a breast.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0097] FIG. 1 is a cross-sectional view of a first embodiment of the invention comprising a stent or dome applied to a breast previously subjected to tissue expansion;

[0098] FIG. 2 is a perspective view of a sheet shaped adhesive element to be adhered to the breast and conform to its shape;

[0099] FIG. 3: is a perspective view of a second sheet of material, adhered to the first and adjustable between deformable and rigid in character;

[0100] FIG. 4 is a cross-sectional view of a second embodiment of the invention, applied to a breast subject to tissue expansion;

[0101] FIG. 5 is a cross-sectional view of another embodiment of the invention comprising what can be a single or multiple layer splint, applied to a breast;

[0102] FIG. 6 is a perspective view of another embodiment of the invention comprising a malleable sheet;

[0103] FIG. 7 is a perspective view of yet another embodiment of the invention comprising a malleable sheet which may be woven or reinforced;

[0104] FIG. 8 is a perspective view of yet another embodiment of a splint that may be pre-formed in the approximate shape of a breast;

[0105] FIG. 9 is a perspective view of a vacuum pump connected to a bra cup for inducing an edema to thereby distend the breast;

[0106] FIG. 10 is a perspective view of yet another embodiment of the invention comprising a splint formed in an approximate circular pattern with a slit for being folded over onto itself and creating an approximate cone shape; and

[0107] FIG. 11 is a perspective view of the cone-shaped splint formed with the circular shaped splint shown in FIG. 10.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

[0108] With reference to FIGS. 1 to 3, the first embodiment is generally referred to as 1. The device (1) is intended to be applied to the soft tissue body area subject to tissue expansion. In this instance, and for illustrative purposes only, the body area consists of a breast (2) whose volume was increased, preferably by injecting a physiologically compatible fluid such as saline, or less preferably by grafting properly treated autologous adipose tissue, in each instance optionally preceded by a period of treatment of vacuum or mechanical stimulation. Nevertheless it is understood that the present invention can be applied in the same way in any surgery, aimed at changing the congenital or acquired body profile through fluid injection or adipose tissue graft, such as in the treatment of depressions caused by scars, surgical resections or malformations. The device is not only limited to external skin surfaces but can also be applied to internal defects and to solid organs.

[0109] The device (1) preferably includes a sheet-like layer of an adhesive element (3), which is preferably made from materials that are easily deformed even at room temperature (about 25° C.) and able to adapt to the widely varying shapes and sizes of the female breast (2). The adhesive element (3) is preferably sheet-shaped, and includes, in correspondence of its outer surface (3a), an adhesive layer (4) that may be applied directly on the skin surface of the breast (2), and a backing layer (5) superimposed to the adhesive layer (4). Both layers (4) and (5) may preferably have a thickness between about 0.5 and 3 mm. The adhesive layer (4) is preferably an hydrocolloid, with high biocompatibility with the skin, so to ensure that the device (1) can be safely and comfortably applied to, and worn on, the breast (2) for reasonably lengthy periods of time, if necessary, without needing replacement. In addition, the biocompatibility of the adhesive layer (4) allows its application on the skin immediately after the surgical breast expansion, even in the presence of post-operative edema which is typically present after these surgical interventions.

[0110] The backing layer (5) is preferably made of soft polymer material, e.g. thermoplastic polyurethane based foam or other polymeric material with similar characteristics of softness and deformability. In this way, the adhesive element (3) can adhere completely to the skin surface of the breast (2), adapting virtually perfectly to its shape. The adhesive elements described above may be provided for example by the company Convatec under the trade name of DuoDerm®.

[0111] The device (1) also preferably includes a structural element (10) coupled to the opposite side of the adhesive layer (4). Even the structural element (10), like the adhesive element (3), is preferably sheet-shaped, with a thickness preferably between 0.5 and 4 mm. The structural element (10) is preferably basically rigid at room temperature, so that it does not deform significantly when subjected to stresses caused by the natural contraction of the body area involved in the tissue expansion. In particular, the structural element (10), at room temperature, is preferably able to resist without deforming significantly when loaded by the natural contraction of the expanded soft tissue, such as the breast (2), following tissue expansion and, among other factors arising from the tissue elasticity and from the post-operative reabsorption of the edema. The material preferably used for the structural element (10) exhibits a high chemical compatibility with the material used for the backing layer (5) of the adhesive element (3), so that it can ensure an effective adhesion to it, even without additional layers of glue. However, it is optionally envisaged that an additional adhesive layer can be applied between the two elements 3 and 10, for example a cyanoacrylate-based material indicated for medical use. Most preferably, the structural element (10) is made of thermoplastic polymer having properties such that when heated to a temperature between 50° and 80° C. (at first instance comparable to the melting point of the polymer), it softens in such a way to be easily deformed by a surgeon's manual manipulation. In this way, the structural element (10) can be stretched over the adhesive element (3), be adapted perfectly to the shape of the breast (2) and maintain this conformation.

[0112] Thermoplastic polymer materials softening at temperatures above 80° C. are not presently considered suitable for use in the present invention, because they would be too hot to be manipulated by a surgeon or to be used on a patient, even in overlap with the adhesive layer (3). On the other hand, thermoplastic polymer materials softening at temperatures below 50° C. are not presently considered suitable for use in the present invention, because they would not have adequate stiffness at room temperature or at temperatures between 35 and 40° C., easily accessible in many countries in summer. Preferably, the structural element (10) is made of a polymer based on polycaprolactone, covered with a layer of urethane acrylates. Several holes with a diameter ranging between 3 and 5 mm are made preferably on the structural element (10) and placed regularly on its surface. These holes (11) allow an easier deformation of the structural element (10) when brought to temperatures between 50 and 80° C., allowing at the same time a decrease of the mass of the structural element (10), in order to be lighter and to provide faster and more even temperature changes both in the heating and the cooling phases.

[0113] The use of this preferred embodiment takes place as described below, at the end of the treatment of tissue expansion of the soft tissue, preferably obtained through the injection of physiologically compatible fluid or grafting of properly treated autologous fat tissue. In the first phase, the adhesive element (3) is carefully laid on the expanded breast (2) to adhere perfectly to the skin surface. After that, the structural element (10) is heated at a temperature between 50 and 80° C. so that the surgeon can easily deform it and lay it on the adhesive element (3) previously applied to the breast (2), adapting to its morphological conformation. The preferable chemical compatibility between the adhesive element (3) and the structural element (10) permits their mutual adhesion. Both the adhesive element (3) and the structural element (10) are laid to cover the entire area involved in the tissue expansion, including preferably a considerable margin around it. The structural element (10) cools rapidly to room temperature, making it stiff enough to hinder effectively the natural tendency to contract of the expanded tissue.

[0114] The sizing and the material of the structural element (10) are such that the cooling takes place as quickly as possible, but long enough to provide the surgeon with the time necessary to lay the structural element on the adhesive element (3). After the application of the structural element (10) and its cooling, the device (1) can be left on the breast (2) for a long period, even weeks if considered desirable, to promote the development of mature fat cells and their integration into the pre-existing tissue. If necessary, the device (1) can be replaced, by detaching the adhesive layer (4) from the breast (2) and repeating the steps described above with a new adhesive element and a new structural element. The device of the present invention is very lightweight and easy to wear, without causing discomfort or pain in the body region around the expanded tissue (breast). In fact, the pressures caused by the tissue's natural contraction is very low, in particular if compared with those necessary to stimulate its expansion by vacuum application as in the known devices. In addition the device of the present invention is customizable, as it is adaptable to the morphology of the specific patient. A further advantage of this invention is that its application promotes a biological response, which is thought to lead to the transformation of the stem cells present in the treated and grafted adipose tissue into mature adipocytes. The structural element (10), before being used, can be provided in the form of a flat sheet or in a convenient alternative, already preformed cup according to different predefined sizes.

[0115] With reference to FIG. 4, another embodiment of the invention is shown and referred to generally as 100 therein. The device 100 differs from device 1 described above by incorporating an additional element with variable thickness 101, interposed between the adhesive element (3) and the structural element (10). The function of this element with variable thickness (101) is to improve the adaptability of the structural element (10) to the morphology of the expanded body region through a controlled reduction of its volume and thickness.

[0116] The element (101) designed with variable thickness is preferably made of polymer foam, e.g. polyurethane, whose radial thickness is adjusted by aspiration of the air contained in it.

[0117] Yet another embodiment 120 is depicted in FIG. 5 and includes within this single drawing figure a number of alternative constructions. For example, there is depicted a stent 122 which has been adhered to a breast with an adhesive layer 124. Stent 122 could have the layer 124 of adhesive applied to its inner surface 126, or the adhesive could be applied separately such as by being sprayed on or as being part of a double-sided, adhesive coated tape 124. Layer 124 could be a layer of gel or silicone and if necessary an additional layer of adhesive could be applied. Layer 124 could also be a layer of second skin. The single layer stent 122 could be formed from a sheet of material (see FIGS. 6 & 7) such as a thermoplastic material, natural or synthetic polymer or from multiple sheets of overlapping material which cures into a rigid construction, like fiberglass or plaster of Paris as might be used for a cast, for example. Stent 122 could also be applied like a putty, such as silicone. There are many other materials, as known to those of skill in the art which could be substituted for these exemplary materials, using the teaching and guidance of the present disclosure.

[0118] As shown in FIG. 6, the stent 122 may be a single sheet of material before application to the soft tissue site; flexible for being readily conformed to the soft tissue site and then being capable of becoming rigid to maintain the morphology of the site. For example, such a flexible single sheet of material 122 may be sized to adequately cover the breast and as explained above have one of its surfaces covered with adhesive or not. As shown in FIG. 7, the stent 122 may be woven or reinforced which can make it both easier to pre-mold into shape and also better hold its molded shape after it is cured or otherwise transformed into a rigid structure adhering to the breast. FIG. 8 depicts yet another representative shape for the stent 122. As shown therein, the stent 122 may be pre-molded into somewhat the shape of different breast cup sizes to minimize the possible introduction of wrinkles as the stent 122 is manipulated around the breast. Also, optionally, a flattened edge surface 126 to help form a seal at the edge of the stent 122 against the patient's chest.

[0119] As shown in FIG. 9, a Brava Bra® system 128 may include a breast cup 130 adhered around a breast and held in place by a vacuum created between them by a pump 132. The periphery may also have an adhesive applied to help hold it in place during wearing. Pump 132 could be either a low pressure pump for continuous use in accordance with the recommended protocol, or a higher pressure pump for recycling as explained above to distend the breast.

[0120] As shown in FIG. 10, the splint or stent 122 may be pre-formed in an approximately circular shape with a slit 134 to facilitate its being folded or collapsed around itself and thereby form the cone shape shown in FIG. 11.

[0121] The methods of use of the various inventions disclosed herein have been explained above as would be readily understood by those of skill in the art.

[0122] The invention has been illustrated through its preferred embodiments as shown in the drawing figures and as described in the description above. These preferred embodiments are not intended to be limiting in any way. Instead, the invention is intended to be limited solely by the scope of the claims appended hereto and their equivalents.