Infusion device and method for drug delivery

A method of infusing a drug, cells, nanoparticles or liposomes in vivo within tissue of an organ of a patient, comprising the steps of:

• inserting a medical device (10) within the patient adjacent the organ, the medical device (10) including an outer cannula (12) having a distal end (14) and a proximal end (16), a handle (18) to which the proximal end (16) of the outer cannula (12) is fixed, and a plurality of microcannulas (20, 22, 24) each defining a lumen extending within a length of said outer cannula (12), distal ends (28) of said microcannulas (20, 22, 24) being retracted within said outer cannula (12) during said inserting step, the handle (18) including an actuator interconnected to the proximal ends (26) of the plurality of microcannulas (20, 22, 24) and movable relative to the outer cannula (12) for advancing and retracting the plurality of microcannulas (20, 22, 24) lengthwise relative to the outer cannula (12), the actuator comprising a plunger (30) extending from a free end of the handle (18) and being slidable relative to and within said handle (18) and not extending within said outer cannula (12), the handle (18) including a longitudinally-extending slot (34) and the plunger (30) including a lateral extension (36) that extends within the slot (34) such that the slot (34) and lateral extension (36) limit the extent of sliding motion of the plunger (30) relative to the handle (18) along a linear path, and the proximal ends (26) of the plurality of microcannulas (20, 22, 24) are interconnected to the lateral extension (36) and extend through the lateral extension (36) such that the proximal ends (26) of the microcannulas (20, 22, 24) and the lumens thereof extend out of and exit the handle (18) through the lateral extension (36) of the plunger (30) and thus through and out of the slot (34) in which the lateral extension (36) extends;
• moving said plurality of microcannulas (20, 22, 24) lengthwise relative to said outer cannula (12) to an extended position by sliding the plunger relative to the handle such that the distal ends (28) of the microcannulas (20, 22, 24) extend beyond the distal end (14) of the outer cannula (12), the outer cannula (12) remaining in a fixed location relative to the organ during said moving step and the plurality of microcannulas (20, 22, 24) being flexible and splaying from each other and the distal end (14) of the outer cannula (12) during said moving step;
• and after said moving step, infusing a pressure-driven drug, cells, nanoparticles or liposomes into the organ simultaneously from the plurality of microcannulas (20, 22, 24).