Device and method for combining a treatment agent and a gel

A method comprising:

• positioning a delivery device at a location in a blood vessel;
• advancing the delivery device a distance into a wall of the blood vessel to a treatment site;
• and
• after advancing the delivery device, introducing a treatment agent and a gel material at the treatment site.

An apparatus comprising:

• a first annular member having a first lumen disposed about a length of the first annular member and a first entry port at a proximal end of the first annular member adapted to accept a treatment agent;
• and
• a second annular member coupled to the first annular member having a second lumen disposed about a length of the second annular member and a second entry port at a proximal end of the second annular member adapted to accept a treatment agent,
• wherein collectively the first annular member and the second annular member have a diameter suitable for placement at a treatment site within a mammalian body, and wherein a distal end of each of the first annular member and the second annular member are positioned to allow a combining of treatment agents introduced through each of the first annular member and the second annular member at the treatment site.