Author: Dayasiri, Kavinda Chandimal
Date published: June 6, 2011
Vocal nodules are a frequently occurring type of voice disorder. Vocal abuse, misuse, and overuse are frequently claimed to be the causes of vocal nodules and their incidence appears to be related to occupation. It is widely believed that the primary aetiologic factor to vocal nodules is trauma to the vocal fold tissues.1 Clinicians use a variety of therapy approaches to treat vocal nodules. A main goal of the treatment techniques is to reduce muscle tension and hyperfunction and optimise vocal behaviour to reduce the trauma to the vocal folds, so that the aerodynamic forces and acoustic properties approach normal values. 1
In Sri Lanka, around 6,000 patients with dysphonia receive voice therapy annually at the ENT clinic of the National Hospital of Sri Lanka. The authors in this study have assessed the therapeutic outcome of voice therapy techniques for patients with dysphonia.
The study was of interventional design, and included pre- and post-assessments to evaluate the effectiveness of voice therapy. Twenty-five female patients (age range 18-60 years) diagnosed with bilateral vocal nodules of any size, and location were included in the study. Initial assessment was followed with regular reassessments by the speech therapist using a previously validated rating scale to evaluate the dysphonia quality. This study included several voice therapy approaches in a broad aspect through 10 voice therapy sessions over a period of six months. A combination of voice therapy approaches are used together to elicit their effectiveness on voice quality and the vocal fold status. The major approaches used in this study were:
1. Vocal hygiene and voice conservation
2. Direct facilitation
4. Easy phonation
5. Yawn sigh
Ethical approval for the study was obtained from the ethics review committee of the National Hospital of Sri Lanka.
Of the 25 participants recruited at the pre-assessment stage, 20 patients completed the voice therapy programme and were available for the post-interventional assessment.
All patients were shown to improve in voice quality to a variable extent after voice therapy (mean pre-voice quality 3.25 compared to mean post-voice quality 8.25; p<0.001). The average difference between pre- and posttherapy was 5 (SND=3.95, p<0.01). The voice therapy had made a significant positive effect to the voice quality of all clients.
Fibre optic laryngoscopy (FOL) or video stroboscopy examinations were conducted to evaluate the vocal fold status of all the patients after completing the 10 sessions of voice therapy. Figure 1 exhibits the vocal fold status for the 20 patients before and after the voice therapy.
All the patients had bilateral vocal nodules at pre-intervention level and most either disappeared bilaterally (60%) or unilaterally (25%) at the post-intervention stage. Only a minority (15%) was left in their initial state, but without any increase of their initial size (Figure 2).
This study result showed that after therapy, the majority of the nodules (85%) had disappeared, and hyper-functional vocal behaviour decreased. The study findings concurred with overseas studies which reported that similar voice therapy for adults significantly reduced, and eliminated vocal-fold nodules and resolved symptoms.2
Although voice therapy is effective in improving voice quality and tissue health, it does not necessarily result in complete resolution of pathology. Therefore, it needs to be considered as part of the treatment regimen for patients with vocal nodules. The high agreement among the investigators as well as the significant parameter changes across voice therapy in this study suggests that perceptual evaluations of voice quality can be made reliable and should have a clinical value. The combined results from perceptual and stroboscopic/FOL evaluations of improved voice quality and absence of vocal nodules suggest that voice therapy had a positive effect in voice quality and vocal fold status.
The combination of therapy approaches shows that it is an effective method of treatment for patients with vocal nodules. Therefore, combined therapy can be established as a voice therapy protocol for patients with vocal nodules.
1. Hillman RE, Hammarberg B, Sodersten M, Doyle P, Holmberg EB. Efficacy of behaviourally based voice therapy protocol for vocal nodules. J Voice. 2001; 15(3):395-412.
2. Cohen SM, Garrett CG. Utility of voice therapy in the management of vocal fold polyps and cysts. Otolaryngol Head Neck Surg. 2007; 136(5):742-6.
Dr.Kavinda Chandimal Dayasiri
Sudharshan T1, Dayasiri MBKC2, Dayasena RP3.
1Senior Speech Therapist, Department of Otolaryngology, National Hospital of Sri Lanka, Sri Lanka.
2Research Officer, Department of Otolaryngology, National Hospital of Sri Lanka, Sri Lanka.
3Consultant ENT Surgeon, Department of Otolaryngology, National Hospital of Sri Lanka, Sri Lanka.