Imageable embolic microsphere

Abstract

This invention concerns imageable, radiopaque embolic beads, which are particularly useful for monitoring embolization procedures. The beads comprise iodine containing compounds which are covalently incorporated into the polymer network of a preformed hydrogel bead. The beads are prepared by activating pre-formed hydrogel beads towards nucleophilic attack and then covalently attaching iodinated compounds into the polymer network. The radiopaque beads may be loaded with chemotherapeutic agents and used in methods of embolizing hyperplastic tissue or solid tumors.

1 - 36 . (canceled) 
     
     
         37 . A radiopaque hydrogel microsphere comprising functional groups on a preformed hydrogel microsphere that have been reacted with an aromatic iodine containing compound. 
     
     
         38 . The radiopaque hydrogel microsphere according to  claim 37 , wherein the iodine containing compound is an iodinated benzyl or phenyl alcohol or is an iodinated benzoic acid. 
     
     
         39 . The radiopaque hydrogel microsphere according to  claim 37 , wherein the iodine containing compound is 2,3,5-triiodobenzoic acid. 
     
     
         40 . The radiopaque hydrogel microsphere according to  claim 37 , wherein the hydrogel microsphere is pre-formed from a polymer comprising alcoholic hydroxyl substituents or acylated derivatives thereof. 
     
     
         41 . The radiopaque hydrogel microsphere according to  claim 37 , wherein the hydrogel microsphere is pre-formed from a polymer comprising a crosslinked polyvinyl alcohol. 
     
     
         42 . The radiopaque hydrogel microsphere according to  claim 37 , wherein the hydrogel microsphere is pre-formed from a crosslinked polyvinyl alcohol which has been formed by copolymerizing ethylenically unsaturated polyvinyl alcohol macromer with ethylenically unsaturated comonomer. 
     
     
         43 . The radiopaque hydrogel microsphere according to  claim 37 , wherein the ethylenically unsaturated polyvinyl alcohol macromer comprises pendant ethylenic groups that are linked via cyclic acetal linkages with oxygen atoms from adjacent hydroxyl groups, that are formed by the reaction of N-acrylaminoacetaldehyde dimethyl acetal. 
     
     
         44 . The radiopaque hydrogel microsphere according to  claim 37 , wherein the hydrogel comprises polyvinyl alcohol partially acetalized with N-formylmethyl acrylamide copolymerized with 2-acrylamido-2-methylpropane sulfonate sodium salt. 
     
     
         45 . The radiopaque hydrogel microsphere according to  claim 37 , further comprising a pharmacologically active agent absorbed within the microsphere. 
     
     
         46 . The radiopaque hydrogel microsphere according to  claim 45 , wherein the pharmacologically active agent is a chemotherapeutic drug. 
     
     
         47 . The radiopaque hydrogel microsphere according to  claim 46 , wherein the chemotherapeutic drug is doxorubicin.