Subdermal cryogenic remodeling of muscles, nerves, connective tissue, and/or adipose tissue (fat)

A system for treating a target tissue of a patient, the system comprising:

• a body comprising a handpiece having a size and shape suitable for supporting in a hand of an operator, and at least one cooling fluid supply path disposed in the handpiece;
• a probe coupled to the body, the probe comprising a probe body and an array of tissue penetrating needles coupled thereto, wherein each tissue penetrating needle comprises a proximal portion, a distal portion, a lumen therebetween in fluid communication with the cooling fluid supply path, the array of tissue penetrating needles extending distally from the probe body and insertable into a target tissue of a patient through a skin surface, wherein at least some of the tissue penetrating needles comprise a fused silica supply tube extending into the tissue penetrating needle lumen;
• a cooling fluid source comprising a single-use cartridge contained in the handpiece, the cooling fluid source coupleable to the fluid supply path, such that when cooling is initiated, direct cooling fluid flows into the penetrating needle lumens so as to cool the target tissue below the skin surface to remodel the target tissue thereby temporarily inhibiting contraction of a muscle and reducing appearance of lines and wrinkles in the face associated with contraction of the muscle;
• and
• an electric heater element having a skin engaging surface, the heater element adjacent the distal end of one or more of the probes, the heater element directing heat energy into the skin to protect the skin surface from injury caused by the cooling.