On the use of opening phase slopes of the glottal signal to characterize unilateral vocal folds paralysis

This paper deals with vocal folds paralysis and the way to identify the pathology by voice analysis. More precisely, it first aims to discriminate between healthy voice and the one produced with unilateral paralyzed vocal folds and secondly to differentiate between different position of “immobile” vocal fold. For such purposes, adequate features are proposed. They are the slopes of the first and the second opening phases. Simulation results validate the features and show that slopes are higher for pathological voices than those of healthy voices. Besides, we remark a decrease in slopes values from median paralyzed (adducted) voice to totally abducted one.