Editing Cannula (section)

=={{Anchor|Blunt-tip}}Aesthetic medicine and anti-ageing==

In [[aesthetic medicine]], a blunt-tip cannula or microcannula (also called smooth tip microcannula, blunt tipped cannula, or simply microcannula) is a small tube with an edge that is not sharp and an extrusion port or pore near the tip which is designed for atraumatic subdermal injections of fluids or gels.

Depending on the size of the internal diameter, it can be used either for the injection of cosmetic wrinkle fillers like [[hyaluronic acid]], collagen, poly-L-lactic acid, CaHA, etc., or for fat transfer ([[Liposuction]]). The American Society for Aesthetic Plastic surgery notes additional soft tissue fillers like calcium hydroxy-apatite and polymethylmethacrylate.<ref>Wu K., Xie L., Wang M., Jiang Y., Tang Y., Wang H. Comparison of the microstructures and properties of different microcannulas for hyaluronic acid injection. Plast. Reconstr. Surg.. 2018;142(2):150E-159E. doi:10.1097/PRS.0000000000004573</ref> The advantage of using these is that they are less painful, have less risk of bruising, have less swelling, and a better safety profile. Accidental intravascular injections are more difficult with blunt-tip microcannulas, reducing the risk of skin necrosis, ulcers, and embolization to the retinal artery which can result in blindness.<ref>{{Cite web |url=http://aiam.us/definitions/blunt-tip-microcannula/ |title=Blunt tip Microcannula |access-date=2012-03-27 |archive-url=https://archive.today/20120707192810/http://aiam.us/definitions/blunt-tip-microcannula/ |archive-date=2012-07-07 |url-status=dead }}</ref> Indeed, in May 2015, the USA issued a warning of these risks as an FDA Safety Communication on the "Unintentional Injection of Soft Tissue Filler Into Blood Vessels In the Face".

In January 2012, the "Dermasculpt" microcannula was approved by the FDA for use in the United States for use with soft tissue fillers<ref>{{Cite journal | last1 = Zeichner | first1 = J. A. | last2 = Cohen | first2 = J. L. |url= https://jddonline.com/articles/dermatology/S1545961612P0070X | title = Use of blunt tipped cannulas for soft tissue fillers | journal = [[Journal of Drugs in Dermatology]] | volume = 11 | issue = 1 | pages = 70–72 | year = 2012 | pmid = 22206080}}</ref> followed by the "Magic Needle", "Softfil", "TSK STERiGLIDE™ by [[Air-Tite Products]]", and "Sculpt-face".<ref>{{cite web|url=http://sculpt-face-canule.fr/en/ |archive-url=https://web.archive.org/web/20160320211306/http://sculpt-face-canule.fr/en/ |url-status=dead |archive-date=2016-03-20 |title=Sculptface|website=sculpt-face.com}}</ref> The primary structural differences between microcannulas is the distance of the extrusion port or pore from the tip (closer is more precise), the bluntness of the tip (tapered blunt tip is easier for entry), and the flexibility of the shaft (enough flexibility to move around sensitive structures but enough rigidity for precise placement).<ref name="auto">{{cite journal|author=Garry R. Lee |url= https://assets.doctorlogic.com/Images/Sites/V/VIPMed/MasterPage/361234.pdf | title = Advanced Anti-Bruising Cosmetic Filler Techniques| journal = PRiME: International Journal of Aesthetic and Anti-Ageing Medicine|date=January–February 2015 | pages = 25–34 }}</ref>

Since microcannula tips are blunt, a Pilot or Introducer needle is required for entry through the skin and the technique is to thread the microcannula through this tiny opening. Microcannula cosmetic injection techniques have been developed on how to best place cosmetic wrinkle fillers such as the Long MicroCannula Double Cross-Hatched Fan and the Wiggle Progression techniques.<ref name="auto"/>

In April 2016, the concept of the use of microcannula to inject more than cosmetic fillers was first published. The technique of Microcannula Injected Local Anesthesia (MILA) was described on the use of microcannula to inject local anesthesia with less pain, bruising, and swelling.  Also introduced were Accelerated Healing After Platelet-Rich Plasma (AHA-PRP), Accelerated Healing After Platelet-Rich Fibrin Matrix (AHA-PRFM), and the use of microcannula to dissolve Sculptra nodules.<ref>{{cite book |author= Garry R. Lee |chapter= Other Microcannula Applications |title= First Book of Aesthetic Microcannula for Cosmetic Fillers and Local Anesthesia (MILA) |date= April 2016 |pages= 98–117  |publisher= CreateSpace Independent Publishing Platform |isbn= 978-1530871094 }} {{ISBN|1530871093}}.</ref>