Summary Lesions to Vagus nerve and its branches

Summary: Lesions to Vagus nerve and its branches 1. Lesions above pharyngeal branch: Adductor paralysis with palatopharyngeal paralysis.

Vagus nerve (all branches) paralysis summary Unilateral: breathiness or whispered voice quality, hoarseness (due to asynchronous vibration), reduced loudness (inefficient glottal closure) and low pitch with possible pitch breaks, occassionally diplophonia; mild-to-moderate hypernasality and nasal emission (due to impaired VP function). Bilateral = severe breathiness or aphonia (if bilateral paralysis is total); weak cough or glottal attack; hypernasality/nasal emission more severe; both folds fixed in abductor position; PROTECTION of airway is of primary concern. ASSOCIATED SYMPTOMS: Depend on extent of weakness and whether involvement is unilateral or bilateral –Difficulty swallowing—due to palatal and pharyngeal muscle involvement –Nasal regurgitation—VP incompetence –Aspiration of secretions—due to palatopharyngeal and laryngeal involvement. Tracheostomy may be necessary if aspiration becomes a problem.

SLN paralysis summary ETIOLOGY: Surgical trauma, accidental trauma, benign thyroid disease. UNILATERAL Lesion: Both folds adduct on phonation, but fold on affected side will appear shorter, and an asymmetric lateral shift of epiglottis and anterior larynx toward unaffected side is seen. VOICE: mild breathiness and hoarseness, normal or mildly reduced loudness, and mild inability to alter pitch often only noticeable when pt attempts to sing. Pt may complain of vocal fatigue. ASSOCIATED SYMPTOMS: laryngeal anesthesia can result in mild postdeglutition cough, choking, or aspiration, or a mild cough after swallowing; often symptoms aren’t constant or obvious thus may not be reported by pt. Bilateral lesion = absence of tilt of thyroid cartilage on cricoid cart. during phonation, folds appear shorter than normal, epiglottis will overhang and obscure anterior portion of folds, will be bowing of folds. Voice = breathiness, hoarseness (mild to moderate), loudness will be reduced, ability to alter pitch will be moderately to severely impaired (serious prob. with singing). Pt may complain of vocal fatigue.

RLN paralysis summary Unilateral Abductor paralysis—affected VF in paramedian position due to action of CT. CT exerts stretch on folds anteroposteriorly, acts as adductor, thus pulling v. folds closer to midline; abductor muscle nonfunctioning, so cannot pull VFs and widen glottis. May have weak cough or glottal attack. ETIOLOGY: Intrathoracic malignant tumor, aneurysms, mital stenosis which causes left auricle to enlarge and impinge on Vagus, trauma to neck, idiopathic (80% resolve within 6 months to 1 year). VOICE: voice usually not affected because both VFs can approximate at midline. If voice affected, will have mild breathy and mild hoarse quality, with slightly reduced loudness and occasional diplophonia. ASSOCIATED SIGNS: May experience shortness of breath during physical activities due to narrowed airway (during periods of deep respiration). MEDICOSURGICAL—delay for 6 -12 months. Rarely is surgery indicated in unilateral abductor paralysis. Voice TX: generally doesn’t require tx. Pts who use voice professionally may require instructions on increased breath control, how to increase intensity, and how to maintain a relaxed vocal tract. Bilateral AB paralysis: breathing for life is an issue; may sacrifice voice for breathing.