Embolization systems

#Embodiments of the present disclosure relate to devices and systems for embolization.

#Migration of conventional embolization coils occurs 4-14% of transcatheter embolizations [2,3]. Non-target embolization is an outcome of coils migration, the impact of which depends on the final location of the coils. In the venous system, the consequences can be catastrophic with literature indicating that coils can migrate into the renal vein, right atrium of the heart, lung (pulmonary artery). Percutaneous retrieval of the coils is technically very challenging and frequently cannot be attempted as the coils are often entrapped within the organs and tissue.

#Coil migration occurs for various reasons: Technical error: release of a coil or coil pack too distal or proximal to an adjoining larger vessel or plexus [6,7] High blood flow areas can cause the coil to migrate. Coil: vessel mismatch. The coils are undersized, hence will not injure the vessel wall, will not induce thrombosis, and are likely to migrate. Or the coils are oversized and will act like a guide-wire and pass further distally into the vessel [8,9]. Vessel dilation: coil migration can occur due to a disparity in the size of coils and dilated vessels, which can change in their diameters depending on vessel hemodynamics [5]. Coils impart a very low radial (anchor) force on the lumen, once a clot forms within the coil, blood flow can force it to migrate.

#The accompanying drawings illustrate certain exemplary embodiments of the present disclosure and, together with the description, serve to explain the principles of the present disclosure. As such, those skilled in the art will appreciate that the conception upon which this disclosure is based may readily be used as a basis for designing other structures, methods, and systems for carrying out the several purposes of the present disclosure. It is important, therefore, to recognize that the claims should be regarded as including such equivalent constructions insofar as they do not depart from the spirit and scope of the present disclosure.

#FIG. 1 is an illustration of a bristle device according to the invention with two types of bristles having different diameters;

#FIG. 2 illustrates the device of FIG. 1 loaded into a tube;

#Referring to the drawings and initially to FIGS. 1 to 8 thereof there is illustrated a bristle device for delivery into a body lumen. The bristle device comprises a longitudinally extending stem 1 and a plurality of bristles extending generally radially outwardly from the stem. In the invention there are at least two different groups or types of bristles.

#In one case a prosthesis with two or more bristle fibre diameters is provided to ensure a low profile for the device when loaded in the catheter 5, and with sufficient anchor force to prevent migration. Smaller diameter fibre bristles 2 are intended primarily to promote and enhance thrombogenicity, while larger diameter fibre bristles 3 are intended primarily to anchor the device in the lumen to prevent migration.

#Lumen occlusion occurs due to thrombogenicity of the device, which is a function of its surface area and its ability to cause stasis. For a given volume of fibre material, many small fibres 2 can be more efficiently fitted into a catheter than few larger fibres 3.