US Patent 10105525 Fluid delivery catheter with pressure-actuating needle deployment and retraction

A fluid delivery catheter that uses micro-needles for fluid delivery though a vessel wall. The catheter may provide fluid delivery therapy for various procedures, such as, for example, delivery of tumescent fluid or renal denervation. The catheter includes an elongate member with deployable and retractable needles disposed about a distal end of the elongate member. The needles may be disposed radially about the distal end and/or along a length of the distal end.