Methods of ablating tissue using a catheter injection system

A method of treating a target tissue, the method including:

• advancing an ablation system through a target vessel until a distal end of the ablation system lies near the target tissue, the ablation system including injection needles, the ablation system designed to allow injection of ablative fluid through the injection needles;
• centering the ablation system with respect to the target vessel by expanding an expandable structure, wherein the expandable structure comprises a balloon;
• advancing the injection needles at least partially through a wall of the target vessel and into the target tissue;
• and
• injecting ablative fluid into the target tissue through the injection needles.

A method of treating a target tissue, the method including:

• advancing an ablation system through a target vessel until a distal end of the ablation system lies near the target tissue, the ablation system including injection needles;
• centering the ablation system with respect to the target vessel by expanding a balloon of the ablation system outward toward a lumenal wall of the target vessel;
• advancing the injection needles at least partially through the lumenal wall and into the target tissue, wherein the balloon is configured to allow the injection needles to be centered with respect to the target vessel;
• and
• injecting ablative fluid into the target tissue through the injection needles.

A method of treating a target tissue, the method including:

• advancing an ablation system through a target vessel until a distal end of the ablation system lies near the target tissue, the ablation system including injection needles;
• centering the ablation system with respect to the target vessel by expanding a balloon of the ablation system, wherein the balloon is configured to enable the circumferential deployment of the injection needles;
• advancing the injection needles at least partially through the lumenal wall and into the target tissue;
• and
• injecting ablative fluid into the target tissue through the injection needles.