Is Patient's "Pitch Understanding" Critical to Better Vocal Outcomes Following Voice Therapy in Vocal Fold Sulcus?

Pitch perception is an individual's ability to distinguish sounds as high or low based on each sound's fundamental frequency (F0). In our voice clinic, F0 and maximum phonation time (MPT) are routinely measured in all patients. However, many of our patients presenting with voice disorders demonstrate poor 'pitch understanding'. Voice therapy is the first-line management for most benign vocal fold lesions, such as vocal fold sulcus. Our hypothesis is to study the role of "pitch understanding" in vocal outcomes following voice therapy, especially in a pathology like vocal fold sulcus where pitch is impacted.

To assess the improvement in vocal outcome measures (MPT and F0) after voice therapy in patients with vocal fold sulcus who understood the concept of pitch versus those who did not.

A 6-month retrospective study was conducted on patients with vocal fold sulcus. Patients with vocal fold sulcus were selected as the study group, as this condition typically presents with hoarseness and elevated pitch. Based on clinic records, patients were divided into two groups: Group A: patients who understood the concept of pitch, and Group B: patients who did not understand the concept of pitch. All patients underwent four sessions of voice therapy over 4-6 weeks. MPT and F0 were recorded before and after therapy. Data were analyzed for changes in outcome measures and compared within and between groups.

Group A included 10 patients who understood pitch concept, 50% (5/10) in this group were singers. Group B included 10 patients who did not understand the concept of pitch, and 0/10 were singers. This was a statistically significant (P = 0.033, P < 0.05) observation. Within Group A, analysis suggested that there was a significant difference in pre vs. post therapy MPT (t = 3.29, P = 0.009); F0 was not statistically significant. Group B analysis showed no significance for both MPT and F0 post therapy. Between Group A and Group B, comparison revealed no statistical significance for MPT and F0, but the effect size (Cohen's d = 0.98) was large for MPT in Group A, suggesting a clinically meaningful effect in this group.

Musical knowledge and training appear to significantly influence the understanding of the concept of pitch. Patients with vocal fold sulcus who understood the concept of pitch had a significant improvement in MPT following therapy as compared to the patients who did not. Incorporating pitch perception training into voice therapy may improve treatment effectiveness and vocal rehabilitation success in this group.