Vocal fold paralysis (VFP) is due to an injury of the vagus nerve or one of its branches and may cause dysfunctions in the glottic competence. The Maximum Phonation Time (MPT) is a test usually applied on dysphonic patients to assess glottic efficiency, mainly in patients with VFP and a decreased phonation time. The clinical classification of the VFP as median, paramedian, intermedian, abduction or cadaveric is controversial. AIM: To check association and correlation between Maximum Phonation Time (MPT) with position and with the displacement angle of the paralyzed vocal fold (PVF), to measure the distal angle of the PVF in different positions from median line, correlating it with the clinical classification. STUDY DESIGN: Chart review. MATERIAL AND METHOD: Records of 86 PVF individuals were reviewed, videoendoscopic exams were analyzed and a computer program measured the distal angle of the PVF. RESULTS: The MPTs for each position of paralyzed vocal fold have statistical significance only for /z/ in the median position. There is a relationship between the MPT of /i/, /u/ with PVF distal angle. Correlation and association of the displacement angle with clinical position demonstrate statistical significance when the PVF is in abduction. CONCLUSION: By the present study it was impossible to classify positions of the paralyzed vocal fold using either MPT or the displacement angle measurement.
larynx; vocal fold paralysis; voice; glottis
