Methods for embolizing vascular sites with an embolizing composition

• US 20040087930A1
• Filed: 10/20/2003
• Published: 05/06/2004
• Est. Priority Date: 05/21/1999
• Status: Abandoned Application

• Current Assignee: Micro Therapeutics, Inc. (Medtronic Plc)
• Original Assignee: Micro Therapeutics, Inc. (Medtronic Plc)
• Inventors: Roth, Noah Michael, Moret, Jacques, Tran, Chinh Ngoc, Hayman, Douglas Ray, Greff, Richard J., Whalen, Thomas J. II
• Application Number:
  US10/689,791
• Publication Number:
  US 20040087930A1
• Time in Patent Office: Days
• US Class Current: 604/509
• CPC Class Codes: A61K 49/0419 Microparticles, microbeads, microcapsules, microspheres, i.e. having a size or diameter higher or equal to 1 micrometer
• CPC Class Codes: A61L 24/001 Use of materials characterised by their function or physical properties
• CPC Class Codes: A61L 24/046 obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds A61L24/043 takes precedence
• CPC Class Codes: A61L 24/06 obtained by reactions only involving carbon-to-carbon unsaturated bonds A61L24/043, A61L24/046 take precedence
• CPC Class Codes: A61L 24/08 Polysaccharides A61L24/043 takes precedence
• CPC Class Codes: A61L 2430/36 for embolization or occlusion, e.g. vaso-occlusive compositions or devices
• CPC Class Codes: A61M 2025/1052 for temporarily occluding a vessel for isolating a sector
• CPC Class Codes: C08J 3/091 characterised by the chemical constitution of the organic liquid
• CPC Class Codes: C08L 29/04 Polyvinyl alcohol; Partially hydrolysed homopolymers or copolymers of esters of unsaturated alcohols with saturated carboxylic acids

Abstract

Disclosed are novel techniques for embolizing blood vessels which are particularly suited for treating vascular lesions via catheter delivery of an embolic composition.

Claims

1. A method for embolizing a vascular site comprising an opening that is in communication with a vascular vessel by delivering via a catheter to said vascular site a composition comprising (1) a biocompatible polymer;

(2) a biocompatible water insoluble contrast agent; and

(3) a biocompatible solvent, said method includes;

(a) positioning the distal end of a delivery catheter in said vascular site wherein the delivery catheter is connected to a source of said composition and whereby said composition can be injected into the vascular site through the delivery catheter;

(b) positioning a flow arresting device (e.g., balloon) at the vascular site to be embolized;

(c) activating the flow arresting device at the vascular site to be embolized such that the activated device substantially arrests blood flow through the vascular site; and

(d) injecting said composition into the vascular site;

(e) deactivating said flow arresting device to permit sufficient blood flow through said vascular site to be embolized such that removal of the biocompatible solvent is facilitated and oxygenated blood is delivered to the tissue distal to said flow arresting device; and

(f) repeating procedures (c)-(e) at least once and as necessary to effect embolization of said vascular site.

2. The method according to claim 1 wherein procedure (c) comprises inflating a balloon so that the inflated balloon has a diameter that is greater than the inner diameter of the vascular vessel.

3. The method according to claim 2 wherein the balloon is inflated to a diameter that is about 100% to 130% of the inner diameter of the vascular vessel.

4. The method according to claim 1 wherein in procedure (e), the balloon is deflated until its diameter is about 10% to 90% of the diameter of the vascular vessel and allowing at least some of the biocompatible solvent to be removed from the vascular site by entrainment in bodily fluid and

15. The method according to claim 1 wherein the viscosity of the composition is at least 150 cSt at 40°

C.

5. A method for embolizing a vascular site comprising an opening that is in communication with a vascular vessel by delivering via a catheter into said vascular site a first embolic composition and then a second embolic composition wherein each embolic composition comprises (1) a biocompatible polymer;

(2) a biocompatible water insoluble contrast agent; and

(3) a biocompatible solvent, said method includes;

(a) positioning the distal end of a delivery catheter in said vascular site wherein the delivery catheter defines a channel that contains first embolic composition and the second embolic composition wherein the first embolic composition is situated adjacent the distal end and the second embolic composition is situated adjacent to the distal embolic composition and whereby said first and second embolic compositions can be injected into the vascular site through the delivery catheter and wherein the first embolic composition has a higher concentration or viscosity of biocompatible polymer than the second embolic composition;

(b) injecting the first embolic composition in said vascular site whereby substantially no axial mixing of the first and second embolic compositions occurs in the channel and, thereafter,

(c) injecting the second embolic composition into the vascular site.

6. The method according to claim 5 wherein procedure (b) comprises applying a first force into the channel to inject said first embolic composition into the vascular site and, procedure (c) comprises applying a second force into the channel to inject said second embolic composition into the vascular site wherein the first force is greater than the second force.

7. The method according to claim 5 wherein, following procedure (b), the first embolic composition forms a nidus (kernel) in the vascular site and following procedure (c) the second embolic forms a precipitate that emanates from the nidus, wherein the precipitate embolizes the vascular site.

8. A method for embolizing a vascular site comprising an opening that is in communication with said site by delivering via a catheter into said site a composition comprising (1) a biocompatible polymer;

(2) a biocompatible water insoluble contrast agent; and

(3) a biocompatible solvent, said method includes;

(a) positioning the distal end of a delivery catheter into the vascular site wherein the delivery catheter is connected to a source of said composition and whereby said composition can be injected into the vascular site through the delivery catheter;

(b) positioning a flow arresting device at the vascular site to be embolized;

(c) injecting DMSO into the catheter to fill the lumen of said catheter followed by injecting a first amount of said composition into said catheter thereby at least a portion of said DMSO is ejected from said catheter into the vascular site and washed downstream therefrom;

(d) activating a flow arresting device at the vascular site so that the activated device substantially seals the opening;

(e) injecting the first amount of said composition from said catheter into the vascular site to form a nidus (kernal) of the embolizing composition;

(f) inactivating the flow arresting device;

(g) determining the volume of the vascular site that has been embolized; and

(h) repeating procedures (e), (f), and (g) as needed to embolize the vascular site.

9. The method according to claim 8 wherein, prior to procedure (c) said method further comprises:

(i) inflating a balloon to a first size in the vascular vessel so that the opening is substantially sealed; and

, before procedure (e)

(j) deflating the balloon.

10. The method according to claim 8 wherein procedure (c) comprises:

(1) filling the catheter with biocompatible solvent (e.g., DMSO);

(2) connecting the catheter to the source of the embolic composition; and

(3) injecting the first amount of composition into the vascular vessel.

11. A method for embolizing a vascular site comprising an opening that is in communication with a vascular vessel by delivering via a catheter to said vascular site a composition comprising (1) a biocompatible polymer;

(2) a biocompatible water insoluble contrast agent; and

(3) a biocompatible solvent, said method includes;

(a) positioning the distal end of a delivery catheter in said vascular site wherein the delivery catheter is connected to a source of said composition and whereby said composition can be injected into the vascular site through the delivery catheter;

(b) activating a flow arresting device in the vascular vessel so that the activated device substantially seals the opening and does not occlude the delivery catheter; and

(c) injecting a single mass (bulk) of said composition into the vascular site wherein the single mass is sufficient to substantially fill the vascular site.

12. The method according to claim 11 wherein the volume of the vascular site to be embolized is measured prior to injecting the single mass in said site.

13. A method for embolizing a vascular site comprising an opening that is in communication with a vascular vessel by delivering via a catheter into said vascular site an embolizing composition including (1) a biocompatible polymer;

(2) a biocompatible water insoluble contrast agent; and

(3) a biocompatible solvent, said method includes;

(a) positioning the distal end of a delivery catheter into the vascular site wherein the delivery catheter is connected to a source of a first embolizing composition and second embolizing composition and whereby said first and second embolizing compositions can be injected into the vascular site through the delivery catheter and wherein the first embolizing composition has a higher concentration or concentration of biocompatible polymer than the second embolizing composition;

(b) injecting said first embolizing composition into said vascular site to form a nidus (kernel) of the first embolizing composition; and

, thereafter,

(c) injecting said second embolizing composition into said vascular site to form a precipitate emanating from the nidus that embolizes the vascular site.

14. The method according to claim 13 wherein, prior to procedure (a) the balloon is inflated in the vascular vessel so that the balloon when inflated seals the opening and does not occlude the delivery catheter, and/or (2) the balloon when inflated has a diameter that is greater than the inner diameter of the vascular vessel.