Acoustic and Physiological Voice Assessment And Maximum Phonation Time In Patients With Different Types Of Dysarthria

Objective: To compare the maximum phonation time of /a/, acoustic glottal source parameters, and physiological measures in patients with dysarthria.

Method: Thirteen patients were classified according to dysarthria type and divided into functional profiles (hypofunctional, hyperfunctional, and mixed). Assessments of maximum phonation time of /a/, glottal source parameters, electroglottography, and nasometry were performed. Results were compared between groups using ANOVA and Tukey posthoc tests.

Results: The highest fundamental frequency differed significantly between groups, with the hyperfunctional profile showing higher values than the other participant groups. Reductions in the maximum phonation time of /a/ and alterations in acoustic glottal source parameters and electroglottography measures were observed in all groups, with no significant differences between them. The remaining measures did not differ between groups.

Conclusion: The maximum phonation times for /a/ were reduced in all participant groups, suggesting air escape during phonation. The presence of alterations in several glottal source parameters in all participant groups is indicative of noise, tremor, and vocal instability. Lastly, the high fundamental frequency in patients with a hyperfunctional profile reinforces the presence of vocal instability. These findings suggest that, although the characteristics observed in the assessments were consistent with expectations of patients with dysarthria, it is difficult to perform a differential diagnosis of this condition based on acoustic and physiological parameters alone.