title: Dynamic high-resolution ultrasound in vivo imaging of hyaluronic acid filler injection.
abstract: BACKGROUND
  High-resolution ultrasound (HRU) imaging is a useful tool to study hyaluronic acid (HA) filler injected in the face.
  
  
  OBJECTIVE
  To observe real-time injection of HA using HRU and describe behavior of the gel injection in various anatomic layers and the effect of massage.
  
  
  METHODS
  Deep (preperiosteal), intermediate (subdermal), and superficial (dermal) injections of HA were performed in the supraclavicular area under ultrasonography visualization on a healthy volunteer. Videos were obtained during injection and static images at several time points, including during injection, immediately after injection, 5 minutes after massage of the treated area, and at 2 weeks after injection.
  
  
  RESULTS
  During injection, dermally injected HA stayed within the dermis, increasing its echogenicity; subdermally injected HA formed multiple anechoic pearls; and preperiosteal HA produced a single anechoic bubble with diffuse margins. No vertical transection of the planes was observed during injection or after massage. Two-week postinjection imaging showed persistence of the varying HA morphology in each plane.
  
  
  CONCLUSIONS
  High-resolution ultrasound allows in vivo study of HA injection behavior. HA adopts different morphology within the tissue depending on the density and compliance of the tissues in the plane of injection.
authors.affiliation: Division of Orbital-Facial Plastic and Reconstructive Surgery, Jules Stein Eye Institute, David Geffen School of Medicine, University of California at Los Angeles, Los Angeles, California.
authors.forename: Jocelyne C
authors.initials: JC
authors.lastname: Kohn
authors.forename: Alice S
authors.initials: AS
authors.lastname: Goh
authors.forename: Joseph L
authors.initials: JL
authors.lastname: Lin
authors.forename: Robert A
authors.initials: RA
authors.lastname: Goldberg
mesh_terms: D001672:Biocompatible Materials; D003357:Cosmetic Techniques; D003879:Dermatologic Agents / Q000627:therapeutic use*; D005145:Face / Q000000981:diagnostic imaging; D005782:Gels; D006801:Humans; D006820:Hyaluronic Acid / Q000008:administration & dosage*; D007271:Injections, Intradermal; D010865:Pilot Projects; D014463:Ultrasonography / Q000379:methods
chemical_list: D001672:Biocompatible Materials; D003879:Dermatologic Agents; D005782:Gels; D006820:Hyaluronic Acid