Related Experiment Video
Updated: Dec 1, 2025

Minimally Invasive Murine Laryngoscopy for Close-Up Imaging of Laryngeal Motion During Breathing and Swallowing
Published on: December 1, 2023
Visual Neurolaryngology
1Voicedoctor.net, Portland, Oregon, USA, thomas@voicedoctor.net.
Abstract:
Visual diagnosis of laryngeal neurologic impairments is not only possible but is perhaps the most accurate method for evaluating the neurologic status of the upper airway. Precise assessments may lead to appropriate treatment without an EMG study. Principles of the neurolaryngology examination include: (1) each muscle has a single action; (2) that action can be elicited and to some degree isolated and visualized; (3) each muscle has an appropriate time to contract; (4) that timing can be compared to the opposite side; (5) inappropriate timing represents reinnervation; (6) inappropriate degree of motion represents reinnervation; (7) patients naturally compensate for any loss; (8) removing compensation during an exam reveals pathology. Some of the visual diagnostic findings available to the astute endoscopic examiner are (1) paralysis, (2) paresis, (3) synkinesis, (4) fixation, (5) tremor, (6) spasm, and (7) reinnervation.
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