Hyaluronidase: from clinical applications to molecular and cellular mechanisms.

Over the past 60 years, hyaluronidase has been successfully utilized in ophthalmic surgery and is now being implemented in dermatosurgery as well as in other surgical disciplines. The enzyme is considered a "spreading factor" as it decomplexes hyaluronic acid (also called hyaluronan, HA), an essential component of the extracellular matrix (ECM). When applied as an adjuvant, hyaluronidase enhances the diffusion capacity and bioavailability of injected drugs. Therefore, the enzyme has been used as a local adjuvant to increase the diffusion capacity of local anesthetics, increasing the analgesic efficacy, and the anesthetized area particularly in the first minutes following injection, resulting in diminished intra- and postoperative pain. In aesthetic medicine, the off-label use of hyaluronidase is considered the gold standard for the management of HA-filler-associated complications. Here, we review the clinical use, underlying biological mechanisms, and future directions for the application of hyaluronidase in surgical and aesthetic medicine.