IMPLANTABLE DEVICES COMPRISING GRAFT MEMBRANES
The invention provides implantable devices and membranes suitable for implantation in a body lumen, as well as methods and processes for their preparation.
1 - 55 . (canceled)
56 . An implantable device for positioning a membrane in a body lumen, the device comprising a frame element and a membrane attached to the frame element, the device having a first, 2-dimensional spatial configuration, and a second, 3-dimensional spatial configuration, the frame element being switchable between the first and second configurations.
57 . The device of claim 56 , wherein the frame element is a closed-loop wire.
58 . The device of claim 56 , wherein in the device's first configuration, the frame element has a polygonal, oval or round 2-dimentional shape.
59 . The device of claim 56 , wherein in the second configuration, the device has a substantially tubular 3-dimentional spatial configuration.
60 . The device of claim 56 , wherein the device is switchable from said first configuration to said second configuration by folding about a longitudinal symmetry axis.
61 . The device of claim 56 , wherein in the device's second configuration, the frame is substantially helical.
62 . The device of claim 56 , wherein the membrane is (i) stretched over at least a portion of the area enclosed by the frame element, or (ii) stretched over the entire area enclosed by the frame element.
63 . The device of claim 56 , wherein the membrane is an animal or a human tissue graft membrane.
64 . The device of claim 63 , wherein said animal tissue graft is prepared from prenatal tissue, postnatal tissue, or adult tissue.
65 . The device of claim 63 , wherein said tissue graft is prepared from a pericardial tissue, a placental tissue, an amniotic membrane and an umbilical-cord tissue.
66 . The device of claim 56 , wherein said membrane having a secant tensile modulus at 20% elongation (E20) of at most 25 N/mm2, optionally wherein the secant tensile modulus at 20% elongation (E20) is between about 0.5 and 25 N/mm2.
67 . A method for obtaining an implantable device of claim 56 , comprising attaching a membrane to a frame element when the device is in its first, 2D configuration, such that the membrane is stretched over the entire area enclosed by the frame.
68 . The method of claim 67 , wherein the membrane is made of an animal tissue graft membrane.
69 . The method of claim 68 , wherein the attachment of the membrane to the frame element is carried out by gluing, suturing, or mechanical anchoring.
70 . The method of claim 68 , wherein the membrane is pre-treated by a de-cellularization process.
71 . The method of claim 68 , wherein the membrane is pre-treated by a process comprising:
(a) immersing the tissue graft in an aqueous solution of at least one cross-linking agent; and
(b) washing the tissue graft with a 0.9% saline solution and/or distilled water.
72 . The method of claim 71 , wherein said at least one cross-linking agent is at least one aldehyde.
73 . The method of claim 71 , wherein (i) said solution of step (a) comprises 0.01-0.4% (v/v) of said cross-linking agent; (ii) the immersion in the cross-linking agent solution is carried out for between about 30 seconds and 30 minutes; and/or (iii) the frame element is pre-treated by polishing, electropolishing, cleaning and/or priming prior to attachment of the membrane.
74 . A process of preparing a membrane suitable for implanting into a body lumen, the process comprising:
(a) providing an animal or human tissue graft;
(b) immersing the tissue graft in an aqueous solution comprising 0.01-0.4% (v/v) of at least one cross-linking agent for between about 30 seconds and 30 minutes, optionally wherein said at least one cross-linking agent is at least one aldehyde optionally selected from glutaraldehyde, formaldehyde, glyceraldehydes, paraformaldehyde, and any combination thereof; and
(c) washing the tissue graft with a 0.9% saline solution, thereby obtaining said membrane.
75 . The process of claim 74 , wherein said animal or human tissue graft is harvested from prenatal tissue, postnatal tissue, or adult tissue, optionally wherein said tissue graft is harvested from a pericardial tissue, a placental tissue, an amniotic membrane and an umbilical-cord tissue.