Comparison of the Degradability of Hyaluronic Acid by Ovine and Recombinant Human Hyaluronidase.

Abstract

Background: The mainstay of treatment in HA filler adverse events is the use of hyaluronidase; however, the dose and dilution are not standardized.

Objectives: The objective of this study is to examine differential dilutions and concentrations of HYAL, as well as comparing the effectiveness of ovine to human HYAL.

Methods: Fillers were selected for study based on a variety of rheologic factors. 0.2ml of product was selected for use based on prior studies. Degradation was assessed comparing both ovine and recombinant HYAL at differential concentrations and dilutions.

Results: In the 2:1 group, by 50 minutes, Restylane Lidocaine degraded with 100U of ovine HYAL. No other complete degradation of fillers was noted. In terms of partial degradation, Restylane Lyft was noted to have partial degradation by 1 hour with 100U of HYAL. In both the 3:1 and 4:1 dilutions, RS and RL fillers were most susceptible to degradation, dissolving within 30 minutes with 100 units of recombinant HYAL and within 40 minutes with 100 units of ovine HYAL. Juvéderm and RHA fillers were the most resistant, requiring 300 units of HYAL for degradation within one hour. Beyond a 3:1 dilution ratio, no further improvement was observed.

Conclusions: This study demonstrates that 300 units of hyaluronidase are sufficient to degrade 0.2mL of the most resistant HA fillers within one hour. Importantly, a minimum dilution of 3:1 should be used to provide adequate fluid for dissolving filler. Lastly, ovine HYAL may be just as effective as recombinant HYAL in terms of dissolving product.