title: Serial computed tomographic and positron emission tomographic properties of injection material used for vocal fold augmentation.
abstract: OBJECTIVE
  This study aimed to demonstrate the radiological properties of hyaluronic acid (HA) and calcium hydroxylapatite (CAHA) on serial computed tomography (CT) and positron emission tomography (PET) scan.
  
  
  METHODS
  Retrospective Case Series.
  
  
  METHODS
  Retrospective chart and imaging analysis of patients who underwent HA or CAHA injection laryngoplasty.
  
  
  RESULTS
  Total of 243 patients who underwent more than one CT of PET after last injection laryngoplasty were included. Sixty-eight patients received HA injection and 175 patients received CAHA injection. In all cases HA showed hypo-density in CT and no abnormal uptake on PET. CAHA showed bright calcific density on CT scan and high uptake on PET but had disappeared with time in 18 months if injected less than 0.85 mL in amount.
  
  
  CONCLUSIONS
  These findings support previous clinical studies on CAHA longevity and provide proper radiological interpretation on injection materials in the vocal folds.
  
  
  METHODS
  IV (Case series).
authors.affiliation: Department of Otorhinolaryngology-Head and Neck Surgery, Seoul National University, College of Medicine, Seoul, South Korea; Research Center for Sensory Organs, Seoul National University Medical Research Center, Seoul, South Korea.
authors.forename: Tack-Kyun
authors.initials: TK
authors.lastname: Kwon
authors.forename: Ji-Eun
authors.initials: JE
authors.lastname: Lee
authors.forename: Won Jae
authors.initials: WJ
authors.lastname: Cha
authors.forename: Chang Myeon
authors.initials: CM
authors.lastname: Song
authors.forename: Myung-Whun
authors.initials: MW
authors.lastname: Sung
authors.forename: Kwang Hyun
authors.initials: KH
authors.lastname: Kim
mesh_terms: D001672:Biocompatible Materials / Q000008:administration & dosage*; D017886:Durapatite / Q000008:administration & dosage*; D006801:Humans; D006820:Hyaluronic Acid / Q000008:administration & dosage*; D007089:Image Enhancement; D058753:Laryngoplasty / Q000379:methods*; D064847:Multimodal Imaging; D049268:Positron-Emission Tomography; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed; D014826:Vocal Cord Paralysis; D014827:Vocal Cords / Q000000981:diagnostic imaging / Q000187:drug effects*
chemical_list: D001672:Biocompatible Materials; D006820:Hyaluronic Acid; D017886:Durapatite
keywords: Computed tomography; calcium hydroxylapatite; hyaluronic acid; medialization laryngoplasty; positron emission tomography