Related Experiment Video
Updated: May 9, 2026

Synthetic, Multi-Layer, Self-Oscillating Vocal Fold Model Fabrication
Published on: December 2, 2011
Serial computed tomographic and positron emission tomographic properties of injection material used for vocal fold
Tack-Kyun Kwon1, Ji-Eun Lee, Won Jae Cha
1Department 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.
Objectives/Hypothesis:
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.
Study Design:
Retrospective Case Series.
Method:
Retrospective chart and imaging analysis of patients who underwent HA or CAHA injection laryngoplasty.
Result:
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.
Conclusion:
These findings support previous clinical studies on CAHA longevity and provide proper radiological interpretation on injection materials in the vocal folds.
Level Of Evidence:
IV (Case series).
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