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Updated: Aug 14, 2026

Subcutaneous Neurotrophin 4 Infusion Using Osmotic Pumps or Direct Muscular Injection Enhances Aging Rat Laryngeal Muscles
Published on: June 13, 2017
Transnasal, endoscopic vocal fold augmentation
Douglas K Trask1, D Luke Shellenberger, Henry T Hoffman
1Department of Otolaryngology-Head and Neck Surgery, University of Iowa Health Care, Iowa City, Iowa 52242, USA. douglas-trask@uiowa.edu
Abstract:
The practice of injection laryngoplasty under local anesthesia has become more common as both the indications for the procedure and the number of injectable substances increased. Modifications to the injection techniques used for vocal fold augmentation have been described over the last decade that reflect changes in the established percutaneous and transoral approaches. These percutaneous and transoral injection techniques for the treatment of dysphonia secondary to glottic incompetence are well described and provide an adequate approach for most cases. However, these traditional methods may be difficult to master, require great patient tolerance, and may be impossible to perform when anatomic or physiologic barriers exist. We describe a new application of the fiberoptic transnasal endoscope to perform laryngeal injection using a flexible needle through a port in the endoscope. This technique is easily mastered and readily tolerated by patients who would not be candidates for the other injection techniques under local anesthesia. We present our favorable experience with this technique and identify its shortcomings coupled with recommendations to address future technical modifications.
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