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Published on: April 21, 2020
[Medialization of the vocal fold in unilateral paresis and paralysis]
S A Karpishchenko1, M A Ryabova1, M Yu Ulupov1
1Pavlov First Saint Petersburg State Medical University, Saint Petersburg, Russia.
Objective:
To evaluate the safety and efficacy of injection laryngoplasty using calcium hydroxyapatite in patients with unilateral laryngeal paresis or paralysis.
Material And Methods:
The study included a retrospective analysis of data from 27 patients (6 men, 21 women) who underwent this procedure between 2020 and 2025. In total, 39 procedures were performed in the study group under local or general anesthesia, 1-4 interventions per patient. The objective examination included computerized acoustic voice analysis with assessment of Jitter (%), Shimmer (%), and HNR (dB).
Results:
A statistically significant improvement in voice function was achieved: the median Jitter decreased from 2.4% to 1.0%, Shimmer from 12.7% to 5.2%, and HNR increased from 7.2 dB to 15.2 dB. Ultimately, permanent medialization was required in 3 patients due to unsatisfactory results; 1 patient developed a complication in the form of acute bacterial laryngitis with a pronounced systemic inflammatory reaction. In 8 cases, calcium hydroxyapatite injection was administered to patients in the early period (within 3 months) after the onset of vocal fold paresis. These patients had developed vocal fold paresis after thyroidectomy and required rapid voice restoration.
Conclusion:
Injection laryngoplasty using calcium hydroxyapatite significantly improves voice quality in patients with unilateral vocal fold mobility disorders.
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