Patent ID: 8380299

Claim:
A process for controllably delivering a treating composition to a tissue structure along an entry track comprising: providing a backflow limiting device, said device having a multilumen catheter including at least one first lumen to provide at least one cryoseal about a catheter-tissue interface at a distance from an injection site, said cryoseal sized and shaped to seal said catheter to said tissue structure, said first lumen in fluid connection with at least one cryogenic source effective for lowering at least a portion of said tissue structure to a temperature within the range of at or about a tissue freezing point to form said cryoseal, and at least one second lumen in fluid communication with a treating composition delivery source and having a delivery end for providing at least one treating composition to an interstitial space within said tissue structure, said delivery end positioned a distance from said cryoseal to allow administration of said at least one treating composition to said tissue at a location which is distal from said cryoseal; said multilumen catheter being constructed and arranged for injecting said at least one composition to a treatment region within said tissue structure prior to, subsequent to, or concurrently with formation of said cryoseal; positioning said backflow limiting device within or proximate to said tissue treatment region; securing said backflow limiting device to said tissue structure by delivering cryogenic agent to a portion of said multilumen catheter lumen, whereby at least one cryoseal is formed proximal to a point of delivery of said treating composition and which is effective to minimize or prevent backflow of said treating composition; maintaining said cryoseal; and delivering said treating composition to said treatment region within said tissue structure by injection; whereby backflow of said treating composition through the entry track is prevented.