[Clinical significance and changes of fibrillation potential amplitude following denervation of laryngeal muscles].

OBJECTIVE: To evaluate the value of clinical application of examination of fibrillation potential amplitude of laryngeal electromyogram. METHOD: Fifty-four patients (65 sides) with recurrent laryngeal nerve paralysis were examined and only the maximum fibrillation potential amplitudes were recorded in the posterior cricoarytenoid muscles and thyroarytenoid muscles. RESULT: There was no significant difference between sexes, ages and sides. The fibrillation potential amplitude was maximum at 3 to 4 months after denervation of the posterior cricoarytenoid muscle or at 5 to 6 months after denervation of the thyroarytenoid muscle and still remained at certain level for years in some patients. Significant difference was showed in complete and incomplete nerve injuries groups, but changes of amplitude with time in incomplete nerve injuries group were small. CONCLUSION: The changes of fibrillation potential amplitude might indicate that the changes from muscle denervation was still reversible and might be more accurate than traditional method of examination.