Volumetric grafts for treatment of fistulae and related methods and systems
View Patent ↗Described are devices, methods, and systems useful in the treatment of fistulae, and in certain embodiments those having openings extending into the alimentary canal, such as anorectal fistulae. Illustratively, an anorectal fistula can be treated by placing a volumetric construct within the primary opening of the fistula. In certain embodiments, the volumetric construct can include a rolled remodelable material processed to form a substantially unitary body. Advantageous such remodelable materials can include collagenous extracellular matrix materials, such as small intestine submucosa.
1. A method for treating a fistula having a primary fistula opening, comprising:
delivering to the fistula a molded graft construct that comprises one or more pieces of sheet-form collagenous extracellular matrix material, wherein the one or more pieces of sheet-form collagenous extracellular matrix material are in a rolled or layered configuration defining contacting layer portions, wherein said contacting layer portions of the rolled or layered configuration are sufficiently dehydrothermally bonded to each adjacent layer portion to provide said molded graft construct as a substantially unitary structure, wherein said molded graft construct includes a generally conical longitudinal segment for lodging within and filling the primary opening with remodelable extracellular matrix material, wherein said one or more pieces of sheet-form collagenous extracellular matrix material include lyophilized collagenous material, wherein said molded graft construct prior to delivering to the fistula has a plurality of passages formed therein with each formed passage including a generally coherent passage wall that extends from an exterior surface of the molded graft construct through contacting layer portions defined by the rolled or layered configuration and into interior regions of the molded graft construct, wherein said plurality of passages are formed in the molded graft construct prior to said contacting layer portions being dehydrothermally bonded to one another so as to enhance uniformity of the matrix structure of said bonded layer portions and said lyophilized collagenous material;
wherein the plurality of passages have a diameter from about 0.1 mm to about 1.0 mm; and
wherein said plurality of passages remain intact after delivering said molded graft construct to the fistula so as to have a coherent passage wall comprising said contacting layer portions.
2. The method of claim 1 , wherein said plurality of passages includes a plurality of elongate cylindrical voids.
3. The method of claim 2 , wherein the elongate cylindrical voids have diameters ranging from about 0.10 mm to about 5 mm.
4. The method of claim 1 , wherein the lyophilized collagenous material in the molded graft construct is substantially uniformly lyophilized.
5. The method of claim 1 , wherein the molded graft construct comprises a plurality of integrally formed protuberances of said collagenous extracellular matrix material on the exterior surface of the molded graft construct.
6. The method of claim 1 , wherein the fistula has a primary opening in an alimentary canal.
7. The method of claim 1 , wherein the fistula is an anorectal fistula, and wherein said delivering comprises lodging said conical longitudinal segment within the primary opening of the anorectal fistula.
8. The method of claim 1 , wherein said one or more pieces of sheet-form collagenous extracellular matrix material are in a rolled configuration.
9. The method of claim 1 , wherein said one or more pieces of sheet-form collagenous extracellular matrix material are in a layered configuration; and
wherein said one or more pieces of sheet-form collagenous extracellular matrix material are in a randomly packed configuration.
10. The method of claim 1 , wherein the collagenous extracellular matrix material retains at least one native growth factor from a source tissue for the collagenous extracellular matrix tissue.
11. The method of claim 10 , wherein the at least one growth factor is Fibroblast Growth Factor-2.
12. The method of claim 1 , wherein the generally conical longitudinal segment tapers from a cross-sectional dimension of about 5 mm to 10 mm to a cross-sectional dimension of about 0.5 mm to 3 mm.