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Published on: June 13, 2017
Single-operator flexible nasolaryngoscopy-guided transthyrohyoid vocal fold injections
1Department of Otolaryngology-Head and Neck Surgery, Division of Laryngology, Stanford University School of Medicine, Stanford, CA 94305-5739, USA.
Objectives:
A number of laryngeal injection techniques have been described for performing vocal fold medialization or delivery of medications, including peroral and percutaneous approaches. Although flexible nasolaryngoscopy-guided injection (FNGI) improves visualization and patient tolerance over rigid endoscopy, the technique requires an assistant to manipulate the laryngoscope. The efficacy and patient tolerance of a novel, single-operator technique for FNGI are evaluated.
Methods:
Patients who required laryngeal injection for vocal fold medialization or for administration of cidofovir or steroids were included in this study. Indications included vocal fold paresis or paralysis, sulcus deformities, recurrent respiratory papillomatosis, vocal fold polyps, and laryngeal granulomas. All procedures were performed in the office setting with topical and local anesthesia with the patient awake. The surgeon performed flexible nasolaryngoscopy with the nondominant hand while using the dominant hand to perform transthyrohyoid injection with a 25-gauge needle with proximal and distal bends.
Results:
Twenty-six patients underwent a total of 42 single-operator FNGI procedures; 19 unilateral and 23 bilateral injections were performed. All but 1 of the procedures were completed with adequate visualization and placement of injectant and good patient tolerance.
Conclusions:
Single-operator FNGI via a transthyrohyoid approach is a viable and versatile laryngeal injection technique for a variety of indications. It provides access to the anterior, middle, and posterior parts of the larynx. It eliminates the need for an assistant experienced in nasolaryngoscopy and allows the surgeon to adjust and optimize visualization in a fashion analogous to endoscopic sinus surgery.
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