title: Histologic Evaluation of Micronized AlloDerm After Injection Laryngoplasty in a Rabbit Model.
abstract: Micronized AlloDerm is a commonly used injectable material for injection laryngoplasty; however, the histologic response to laryngeal implantation and resorption rate over time have not been elucidated. This study aimed to evaluate the in vivo response of micronized AlloDerm over time after laryngeal implantation using a rabbit model.
  
  
  
  Animal model.
  
  
  
  The left recurrent laryngeal nerve was sectioned in five New Zealand White rabbits to create a vocal cord paralysis. Two weeks later, injection laryngoplasty was performed with 100 μL of micronized AlloDerm. Animals were sacrificed 4 (two rabbits) and 12 (three rabbits) weeks after injection. Histologic sections were stained and evaluated by a single pathologist. Volume estimates were made by assuming the implant took an ellipsoid shape using dimensions calculated from histologic slides.
  
  
  
  In all cases, histological analysis revealed a lymphocytic inflammatory response infiltrating the peripheral margins of injection. After 4 weeks, the volume of injected material remaining in two rabbits was 404 and 278 mm3(average 341 mm3). After 12 weeks, the volume of injected material remaining in three rabbits was 0, 61, and 124 mm3(average 62 mm3), an 82% difference in volume of material between animals sacrificed at 4 weeks versus 12 weeks.
  
  
  
  Injection laryngoplasty using micronized AlloDerm induces a lymphocytic inflammatory response after injection in a rabbit model. Though a significant amount of material remains after 4 weeks, by 12 weeks the majority has been reabsorbed.
  
  
  
  NA Laryngoscope, 127:E166-E169, 2017.
authors: Department of Otolaryngology-Head and Neck Surgery, Mayo Clinic School of Medicine, Rochester, Minnesota, U.S.A.
authors: Michael S
authors: MS
authors: Oldenburg
authors: Department of Otolaryngology-Head and Neck Surgery, Mayo Clinic School of Medicine, Rochester, Minnesota, U.S.A.
authors: Jeff
authors: J
authors: Janus
authors: Department of Otolaryngology-Head and Neck Surgery, Mayo Clinic School of Medicine, Rochester, Minnesota, U.S.A.
authors: Steve
authors: S
authors: Voss
authors: Department of Otolaryngology-Head and Neck Surgery, Mayo Clinic School of Medicine, Rochester, Minnesota, U.S.A.
authors: Serban
authors: S
authors: San Marina
authors: Department of Anatomic Pathology, Mayo Clinic School of Medicine, Rochester, Minnesota, U.S.A.
authors: Tiffany
authors: T
authors: Chen
authors: Department of Anatomic Pathology, Mayo Clinic School of Medicine, Rochester, Minnesota, U.S.A.
authors: Joaquin
authors: J
authors: Garcia
authors: Department of Otolaryngology-Head and Neck Surgery, Mayo Clinic School of Medicine, Rochester, Minnesota, U.S.A.
authors: Dale
authors: D
authors: Ekbom
mesh_terms: D000818:Animals; D003094:Collagen / Q000008:administration & dosage*; D004195:Disease Models, Animal; D007267:Injections; D058753:Laryngoplasty / Q000379:methods*; D011817:Rabbits; D012009:Recurrent Laryngeal Nerve / Q000601:surgery*; D013997:Time Factors; D014826:Vocal Cord Paralysis / Q000601:surgery*
chemical_list: C440568:Alloderm; D003094:Collagen
keywords: Micronized AlloDerm; histologic fate; vocal cord paralysis