Plasma gel as a new augmentation material for injection laryngoplasty in rabbit model: Histologic analysis

Objectives. Currently, a variety of materials are available for the treatment of glottal insufficiency. Ideal injection materials should be inexpensive, easily obtainable, nontoxic, and biocompatible. Plasma gel has recently been developed as an injectable, autologous material used in plastic surgery. The aim of this study was to evaluate the histological changes in rabbit vocal folds (VFs) after an injection of plasma gel, compared with collagen (Artecoll) or hyaluronic acid (Reviderm Intra). Study Design. Experimental prospective animal study. Setting. Animal laboratory. Subjects and Methods. Blood samples were collected from 12 New Zealand rabbits. Plasma collected from each rabbit was centrifuged and processed using a gel heating system. All rabbits received a 0.05 ml injection of plasma gel into the right VF, while an equivalent volume of Artecoll or Reviderm Intra was injected into the left VFs of each 6 rabbits randomly. The larynges were collected 2, 4, and 8 weeks after injection, and the tissues were stained for histological analysis. Results. In comparison with left VFs injected with Artecoll or Reviderm Intra, there was significantly less inflammatory response and foreign body reaction in the plasma gel injected right VFs (P ≤ .05). Multinucleated foreign body type giant cells were also more prevalent in the left VFs. There were no quantitative differences in the rates of neovascularization or collagen deposition between groups. Conclusion. Plasma gel is a biologically compatible material that may serve as a suitable augmentation material in injection laryngoplasty. Further studies that examine the longterm effects in a larger number of subjects are needed.