Abstract
Calcium phosphate bone paste (BIOPEX®) is a material for medical use to cover bone defects. It changes from a paste form to hydroxyapatite solid form with time and offers many advantages as a material for vocal fold injection. Preparation and injection procedures are easy because the material is provided in a kit and is a paste form when injected. As material absorption is minimal over a long period, therapeutic effect is stable for long duration. In addition, its solidity after injection enables this material to be used in patients with large posterior glottal gap. The technique we established calls for injection of the material into the lateral side of the vocal process to the adduct arytenoid cartilage using an expandable laryngoscope (FK or Weerda type) and video laryngo-pharyngoscope system. Holding with forceps after injection, to keep the cartilage in good position for a few minutes until the material solidifies, makes this procedure more successful. We also invented a novel trans-oral vocal fold closing method by injecting BIOPEX into both vocal folds taking advantage of arytenoid adduction. Vocal fold injection with BIOPEX in this trans-oral technique has effect similar to thyroplasty type I and arytenoid adduction.
