Inform clients and caregivers about voice disorders. Provide guidance on how to reduce symptoms’ impact while increasing communication.
Provide insight into how dysarthria symptoms may progress over time and recommend appropriate services, including augmentative and alternative communication such as augmentative and alternative communication services provided by ASHA through its Practice Portal resource on Augmentative and Alternative Communication. Identify whether an underlying condition such as cancer or stroke might be contributing to voice dysfunction.
Physiology
Resonant voice therapy employs behavioral strategies designed to improve voicing. The goal is easy phonation with high amplitude vibration (louder sounds) and reduced vocal fold impact stress. Resonant voice therapy has proven particularly useful for treating children diagnosed with cleft palate or VPD speech disorders; however, its applicability extends further – as evidenced by professional singers and actors using it effectively to improve vocal quality.
SLPs can identify potential resonance disorders and provide appropriate assessment, intervention and evaluation services. Screening should involve gathering a comprehensive medical history on the disorder to understand its onset, course and surgical history before conducting an acoustic analysis to ascertain its aetiology – such as hypernasality or nasal emission symptoms – along with any other issues impacting vocal quality or function that require medical intervention.
Acoustic analysis should also be undertaken, to ascertain whether the cause is from VPM or other factors, such as anatomy of pharynx and nasal cavity, presence of other craniofacial issues or hearing loss. Such information can help in both differential diagnosing the disorder as well as selecting the most effective treatment approach.
Referral to a craniofacial or cleft palate team may be necessary in some instances for surgical or prosthodontic management; when this occurs, the SLP can act as an advisor and collaborator on behalf of this team to ensure anatomically based speech and swallowing problems are identified and corrected as soon as possible.
Treatment options for children who struggle to articulate include altering vowels and consonants in their language to alter the resonance pattern of their voice, while techniques like adduction and barely abducted glottal configurations have shown increased vibration amplitude with reduced vocal fold impact during phonation, thus making phonation simpler for them.
Resonant voice therapy and diaphragmatic breathing techniques are often utilized by children with cleft palate/VPD to reduce nasal emissions and enhance their voice sound. Complying with voice programs may prove difficult in this population, yet their physical outcomes – decreased fatigue, pain and effort while speaking can motivate kids to engage with treatment programs.
Symptoms
People suffering from voice disorders may exhibit various symptoms. These may include difficulty speaking at normal volume levels, reduced or lost intelligibility, or increasing effort required to produce sound (i.e. vocal fatigue). An experienced clinician can distinguish between symptoms and disorders based on what causes their dysfunction.
An accurate medical history is key to understanding the origin and course of a problem, surgical history and associated conditions. For instance, intermittent dysphonia with airway distress could be indicative of gastroesophageal reflux disease while persistent hoarseness that requires increased effort can indicate vocal cord nodules.
VPD may have structural causes. These may include an overt or submucous cleft palate; an open adenoid space; large tonsils that intrude into the pharynx and prevent closure; scar tissue post-adenectomy that intrudes into their tonsils, deep pharynx (palatopharyngeal disproportion), deep pharynx depth or even vocal fold granulomas as possible sources.
Behavioral speech therapy cannot address resonance disorders caused by structural abnormalities; however, changes to articulation placement can have positive results when implemented. Please see ASHA’s Practice Portal page on Cleft Lip and Palate for more information on changing placement of affected sounds. Hyponasality is another symptom of VPD which includes decreased nasal resonance and energy on vowels, sonorants and nasal consonants – this may occur alongside denasalization, which involves making them sound more oral in nature (e.g. /b/ for /m/ and /n/).
Other therapies to help reduce or improve VPD include Smith Accent Technique, which helps coordinate vocal fold vibration with air pressure and airflow; Expiratory Muscle Strength Training (EMST), which strengthens muscles of the chest and abdomen; Lee Silverman Voice Treatment LOUD specifically tailored for people living with Parkinson’s disease; as well as changing how one speaks in order to make their voice more powerful and clear – for instance resonant voice therapy was successful in helping one fifth grade boy who experienced voice loss and fatigue use resonant therapy to decrease his reliance on vocal rest behaviors while simultaneously developing phrased productions as part of his productions during dialogues between two people interacting in conversations.
Assessment
Resonant voice therapy (Gartner-Schmidt, 2020) provides an inclusive treatment approach for muscle tension dysphonia (MTD). It involves teaching the vocal tract to tune properly with its sound source so as to allow vocal folds to move without tightness, producing a powerful yet clear voice. Resonant voice therapy includes various exercises ranging from simple to complex techniques and exercises that emphasize first formant tuning for improved sound quality and louder volume perception.
Speech-language pathologists must consider each person’s cultural and linguistic environment when diagnosing and treating resonance disorders. Some may have an emotional attachment to their native language and be reluctant to alter pronunciation for better communication; this can make someone sound foreign to others or lead to miscommunication. SLPs must also recognize that dialect differences may greatly vary acoustically – thus emphasizing the importance of evaluating each voice within normal parameters.
Perceptual assessments such as GRBAS scale and CAPE-V assessments are key in diagnosing velopharyngeal dysfunction; however, objective measures such as acoustic and aerodynamic evaluations offer additional documentation of changes to vocal quality over time. Such tools are especially beneficial in gauging severity of voice disorders as well as tracking effectiveness of interventions.
Clinical trials have assessed the efficacy of resonant voice therapy as a means to improve overall vocal quality in individuals. While results have varied from trial to trial, many have discovered that resonant voice therapy can significantly decrease breathy sounds while increasing clarity and intelligibility of speech while decreasing effortful speaking.
Other treatments for muscle tension dysphonia include Flow Phonation, which instructs patients to focus on airflow rather than tightness or muscle tension during phonation. This method has proven particularly successful against illness- or surgery-induced dysphonia as well as injury, aging or medical conditions causing muscular tension dysphonia in voice users. Unfortunately, its effectiveness can be difficult to gauge without knowing where their starting point was initially.
Treatment
Resonant voice therapy aims to relieve vocal fold impact stress and effort, as well as to enhance voice quality. Sessions often consist of diaphragmatic breathing, lip trills, stretching exercises, neck massage and laryngeal massage as treatment components; feedback methods and intensity levels vary widely between treatments sessions.
Speech and language pathologists utilize resonant voice therapy to treat patients suffering from various resonance disorders, including those related to cleft palate or velopharyngeal dysfunction (VPD). Treatment is focused on creating a strong, clean voice with minimum effort or strain placed upon it between vocal folds in order to minimize strain and prevent injury.
VPD may result from enlarged tonsils or adenoids limiting laryngeal closure, leading to increased vocal cord vibration and force between them, increasing force between them, as well as from overgrowth of vocal chord vibration fibers (Kotby & Fex, 1998). A granuloma may also contribute. A vocal thyroplasty procedure known as palatal implants may help people suffering from VPD due to anatomical causes like an abnormal tongue position or motor planning/execution issues leading to irregular opening/closing patterns during laryngeal closure.
Resonant voice therapy can also be an effective solution for treating stuttering, cluttering and other fluency disorders. For more information, see ASHA’s Practice Portal resources on Adult Dysphagia and Swallowing Disorders.
Resonant voice therapy can be a useful approach to treating dysarthria. Treatment typically entails repeating simple and complex syllables and words to assess apraxia and motor speech planning/programming (ASHA, 2018). Other possible therapies may include prosody – the use of variation in pitch, loudness, duration to convey emotion emphasis or language information (Freed, 2020). Speech therapists may use Lee Silverman Voice Treatment or LSVT LOUD to decrease high phonatory effort that affect intelligibility/voice quality as well as Pitch Limiting Voice Treatment to increase vocal volume without increasing pitch (de Swart et al., 2022).