Does hyaluronidase injected in periocular area change skin ultrastructure?: Standardized in vitro analysis

Treatment with hyaluronic acid (HA) fillers as a strategy for rejuvenation has experienced a significant growth in recent years, accompanied by a parallel increase in its complications, the treatment of which, such as hyaluronidase, we must be aware of.14 patients (28 eyes) had indication for upper blepharoplasty surgery in the Hospital Universitario y Politécnico La Fe. After surgery, periocular skin of one eye of each patient was infiltrated with 300 U of hyaluronidase (14 cases) while the skin of the fellow eye was preserved untreated (14 controls). All samples were studied by the Pathology department, and finally, 6 variables (skin structure alteration, degeneration of elastic fibers, deposits, collagen fibers destructuring, inflammation, and other findings) were analyzed.No differences in skin structure, elastic fibers, and collagen dermal fibers were found between hyaluronidase-treated skin and controls. A significant association between ex vivo application of hyaluronidase in periocular skin and the presence of amorphous extracellular deposits within the dermis was found.Hyaluronidase applied ex vivo to periocular skin led to presence of deposits within the extracellular matrix compared to control eyelid skin but elastin and collagen dermis structure remained unaltered.