BACKGROUND

Many procedures are intended to change the surface appearance of the skin by reducing lines and wrinkles. Some of these procedures involve injecting fillers or stimulating collagen production. More recently, pharmacologically based therapies for wrinkle alleviation and other cosmetic applications have gained in popularity.

Botulinum toxin type A (BOTOX) is an example of a pharmacologically-based therapy used for cosmetic applications. It is typically injected into the facial muscles to block muscle contraction, resulting in temporary paralysis of the muscle. Once the muscle is disabled, the movement contributing to the formation of the undesirable wrinkle is temporarily eliminated. Another example of pharmaceutical cosmetic treatment is mesotherapy, in which a cocktail of homeopathic medication, vitamins, and/or drugs approved for other indications is injected into the skin to deliver healing or corrective treatment to a specific area of the body. Various cocktails are intended to affect body sculpting and cellulite reduction by dissolving adipose tissue, or skin resurfacing via collagen enhancement. Development of non-pharmacologically based cosmetic treatments also continues. For example, endermology is a mechanical based therapy that utilizes vacuum suction to stretch or loosen fibrous connective tissues, which are implicated in the dimpled appearance of cellulite.

While BOTOX and/or mesotherapies can temporarily reduce lines and wrinkles, reduce fat, or provide other cosmetic benefits they are not without their drawbacks, particularly the dangers associated with injection of a known toxic substance into a patient, the potential dangers of injecting unknown and/or untested cocktails, and the like. Additionally, while the effects of endermology are not known to be potentially dangerous, they are brief and only mildly effective.

In light of the above, it would be desirable to provide improved medical devices, systems, and methods, particularly for treatment of wrinkles, fat, cellulite, and other cosmetic defects. It would be particularly desirable if these new techniques provided an alternative visual appearance improvement mechanism which could replace and/or complement known bioactive and other cosmetic therapies, ideally allowing patients to decrease or eliminate the injection of toxins and harmful cocktails while providing similar or improved cosmetic results. It would also be desirable if such techniques were performed percutaneously using only local or no anesthetic with minimal or no cutting of the skin, no need for suturing or other closure methods, no extensive bandaging, and limited or no bruising or other factors contributing to extended recovery or patient “down time”.

SUMMARY

The present invention is directed to targeted delivery of a cold slurry underneath a patient's skin to improve the cosmetic appearance of the skin. The appearance of undesirable wrinkles or lines in the skin can be caused by the contractions of muscle tissue that underlie the skin. Tissue that is the target of cold slurry treatment can be a muscle, a nerve that innervates a muscle or a combination of muscle and innervating nerve. Cooling the muscle and/or nerve with the cold slurry can inhibit the muscle from contracting, thereby reducing the appearance of wrinkles or lines. The target tissue can also be adipose tissue that causes overlying tissue to sag and to form wrinkles or lines. The cold slurry cools the adipose tissue and induces apoptosis, which reduces the size of the tissue. The cold temperature simultaneously causes connective tissue supporting the skin to thicken and tighten, thereby reducing the wrinkles or lines. Cold slurry can also be used to treat cellulite and acne.

Skin can also be tightened by way of a cold slurry injection into the dermis layer of the skin or within the layers of the oral mucosa. When injected into loose skin, the cold slurry induces the production of connective tissue around the injection site, which may be due to stimulated collagen production, new elastin formation, fibrosis, or tissue compaction. The skin tightening effect can, for example, reduce the appearance of baggy skin after a patient loses weight. The cold slurry injection is non-invasive and can be done on an out-patient basis making it a convenient way of treating loose skin around a patient's flanks, abdomen, thigh, upper arm, and submental area under the chin, for example. In another example, inducing connective tissue production in the oral mucosa with cold slurry can make the oral mucosa more resistive to collapsing when a patient sleeps. As such, cold slurry is an ideal treatment for obstructive sleep apnea.

The cold slurry can be provided to the target tissue with a delivery device having a cannula. An example of such a device includes a syringe. The cold slurry can be generated within the device itself or within a separate chamber, both of which produce a cold slurry at the point of care using a cooling source and an injectable fluid. Preferably, the cold slurry comprises water, 0.1% to about 20% glycerol, and 0.1% to about 20% salt. The mean temperature of the cold slurry can be about +10° C., about +7° C., about +5° C., about +4° C., about +3° C., about +2° C., about +1° C., about 0° C., about −1° C., about −2° C., about −3° C., about −4° C., about −5° C., about −10° C., about −15° C., about −20° C., about −30° C., about −40° C., or about −50° C. The cold slurry can have ice particles that are preferably spherical or round in shape with a diameter of about 1 mm to about 0.01 mm.

