Precise evaluation is helpful in determining the best course of treatment for each patient. In neurologic injuries, the degree of glottic incompetence will predict the value of arytenoid adduction as a supplement to vocal cord medialization. Electromyography has been helpful in these cases by detecting recovery earlier, and by identifying synkinesis which might be helped by botulinum toxin therapy. In cases of spasmodic dysphonia, the pre-treatment EMG establishes the degree of impairment and identifies the muscles most involved in the dystonia. This information has been useful especially in patients who do not respond to the usual doses of botulinum toxin.
Additional resources are important for the evaluation of some voice disorder patients.
Gastroesophageal reflux has been clearly implicated in numerous disorders such as muscle tension disorder, vocal cord erythema, and vocal cord thickening. While conclusive studies have not been done, there is speculation that reflux can be contributory to the etiology of malignant laryngeal lesions. A thorough history, and if needed, an evaluation by gastroenterology, are important adjuncts to the laryngologic examination. The larynx is also occasionally involved initially in numerous neurological disorders. Parkinson's Disease, myasthenia gravis, amyotrophic lateral sclerosis, as well as other entities can be first diagnosed during a laryngeal evaluation.