Individuals with cleft lip and palate often demonstrate multiple problems such as early feeding difficulties, nutritional issues, developmental delays, abnormal speech and / or resonance, dentofacial and orthodontic abnormalities, hearing loss, and possibly, psychosocial issues. A coordinated team approach involving follow-up from infancy to adulthood is recommended for optimal outcomes.
In the past decade, there has been a significant increase in the number of surgeons who provide services for individuals with cleft lip and palate in India. It is well accepted that the primary purpose of palate repair is to facilitate speech production.Thus, there has been great interest in the measurement of surgical outcomes, candidacy for secondary surgeries for speech, and speech therapy. Speech-language pathologists evaluate language, speech, resonance, and velopharyngeal function in individuals with cleft lip and palate and make recommendations for appropriate treatment. They also provide intervention for communication disorders. This article provides an orientation for members of cleft care teams on speech and language disorders in this population.
Individuals with cleft lip and palate form a diverse group varying from those who have an isolated cleft, to those in whom cleft lip and palate is more of a feature of a syndrome. This diversity makes it difficult to make generalizations about the characteristic features of communication disorders in those with cleft lip and palate. D'Antonio and Scherer listed several factors: type and severity of cleft, age and time of palate repair, efficacy of repair, unrepaired residual cleft, presence of fistula, status of velopharyngeal function, hearing status, and socioeconomic and linguistic status that could impact communication in this population. They also emphasized the need to keep a developmental perspective in mind as the management (surgical, dental, or speech) is timed with reference to physical growth and development.
The first priority for a child born with cleft lip and palate is feeding. This is to ensure that the child meets the nutritional and growth requirements needed for surgery. There has been much debate and research in developed countries on delineating the most appropriate timing for palate repair that would be optimal for the development of speech without compromising orofacial growth. In many regions of the developing world, late palate repair is the rule rather than an exception because of the paucity of trained manpower and resources. A child with a cleft of lip and palate may never be referred to a speech pathologist, or be referred only if and when a problem in communication becomes evident. Furthermore, speech pathology may be nonexistent as a profession or be in its infancy in many of these countries.
There have been several reports that children with cleft lip and palate show delayed expressive language, evidenced by slower acquisition of sounds and words and restricted inventory of sounds in early infancy. It was also believed that they catch up by the age of three, usually after palate repair. Recently, a number of studies have documented that the children with cleft lip and palate show delays in language development that may encompass both receptive (comprehension) and expressive (production) language. Some reports suggest that these early difficulties in the acquisition of language may persist into childhood in some individuals. In the light of such evidence, it is important for infants and young children with repaired / unrepaired cleft lip and palate to be assessed for language development.
In the past decade, there has been a paradigm shift in the approach towards the management of communication disorders in very young children with cleft lip and palate. There is an increasing emphasis on the identification of “at risk” children. The recognition of differences in language and speech development in infants and young children with cleft lip and palate has resulted in several investigators exploring early intervention models that incorporate language stimulation techniques involving play therapy and parent infant programs. It has been demonstrated that these intervention models not only improve language skills, but also promote speech sound production. Scherer, D'Antonio, and McGahey reported reduction in compensatory errors, a finding that has important implications in underserved regions of the world where a “prevention model” may be easier and more practical to implement.
Even with early surgical repair, a majority of preschoolers demonstrate delays in speech sound development and have typical cleft palate speech. The term, ‘cleft palate speech’ is used to describe phenomena such as atypical consonant productions, abnormal nasal resonance, abnormal nasal airflow, altered laryngeal voice quality, and nasal or facial grimaces. A profile of communication disorders in 129 individuals with repaired cleft of lip and / or palate above the age of three years from a district in South India, revealed that 38% had normal and age-appropriate communication skills. The majority of those with normal communication skills had isolated cleft of the lip. Forty-three percent of the 129 individuals exhibited abnormalities in articulation and resonance, 12% had only articulation deviations, and 3% only abnormalities in resonance. Another 3% of these individuals exhibited delays in language development. In order to appreciate the effect of cleft on speech, it is essential to understand the mechanism of speech production.
The production of speech involves a series of coordinated movements that begins with airflow from the respiratory system. This airflow is modulated at the laryngeal, articulatory, and resonatory systems, producing different sounds. For precise production of various sounds, it is also necessary to have effective feedback and control, which requires an intact auditory and neuromotor system. Various sounds are produced across the vocal tract, depending on the place and the manner of these modulations. The vowel sounds are produced without any significant constriction made by the tongue / lip, and are classified based on the position and height of the tongue and rounding of the lips. For example, the vowel /a/ as in ‘arch’ is described as a low mid vowel; /i/ as in ‘inch’ is described as a high front vowel; while /u/ as in ‘soup’ is a rounded high back vowel. The consonants are classified as glottal, pharyngeal, velar, palatal, retroflex, alveolar / dental, labiodental, and bilabial, based on the place of articulation, i.e., the place where a constriction is made by the tongue / lip.
In individuals with cleft lip and palate, errors in speech production are noticed due to the abnormalities in oronasal structure / function, orofacial structure and growth, learned neuromotor patterns during early infancy, and / or disturbed psychosocial development. A wide variety of speech sound errors are noticed in these individuals. Comparatively, the pressure consonants (stops, fricatives and affricates) are more affected than the other sounds. Henningsson et al. summarized the various atypical consonant productions that can be observed in individuals with cleft lip and palate.
Abnormal nasal resonance is another characteristic feature in most individuals with cleft lip and palate. The resonance of speech is largely determined by the size and shape of the oral, nasal, and pharyngeal cavities, and the functioning of the velopharyngeal valve. The abnormal nasal resonance in cleft lip and palate could involve either hypernasality or hyponasality. Hypernasality refers to an excessive nasal resonance that is perceived for vowels and oral consonants. Hyponasality indicates a decreased nasal resonance for nasal consonants and vowels. In some individuals with cleft, hypernasality and hyponasality co-exist, resulting in a mixed nasality. Abnormal resonance can be caused by structural disturbances such as obstructions in the nasopharynx due to adenoid hypertrophy, swelling of the nasal passages secondary to allergic rhinitis, or hypertrophic tonsils (causing hyponasality), large oronasal fistula, and velopharyngeal dysfunction (causing hypernasality). Occasionally, hypernasality could be caused due to velopharyngeal mislearning, wherein only certain sounds are perceived to be hypernasal. This is referred to as phoneme-specific hypernasality, which occurs due to the incorrect placement of oral structures for certain sounds (e.g., ng/l, ng/r).
Conditions such as large oronasal fistula and velopharyngeal dysfunction (VPD) will also result in disturbed nasal airflow in addition to hypernasal resonance. These conditions result in air emission while attempting to produce pressure-sensitive sounds. The loudness of this emission is determined by the size of the opening (fistula or velopharyngeal port). Phoneme-specific nasal air emission can also be noticed due to velopharyngeal mislearning.
Very often, resonance and airflow disturbances in individuals with cleft lip and palate are due to VPD. Shprintzen reported that 10–20% of children undergoing primary palatoplasties before the age of 18 months have associated VPD. The occurrence of VPD may be much higher in children who undergo primary palate repair at later ages.
Individuals with cleft lip and palate may also exhibit dysphonia. This is characterized by breathiness, hoarseness, and low intensity of voice during speech tasks. This is usually due to increased respiratory and muscular effort, and hyper-adduction of vocal folds while attempting to close the velopharyngeal valve. The presence of dysphonia often masks nasality, making perceptual evaluation difficult.
Speech intervention for individuals with cleft lip and palate can begin even before the palate is repaired. In very young infants, the emphasis is on training the parent / caregiver to stimulate the child's ability to understand and use language. Studies have demonstrated the efficacy of early intervention models using parents in the prevention of compensatory errors. There is a need to apply and analyze the efficacy of such programs in the Indian scenario.
Older children (about age three) can be involved in direct therapy for the correction of errors in speech sound production (misarticulation). The goals are to establish the correct placement of the oral structures for speech sound production and directing the airflow appropriately. Goals are set depending on the error patterns and the age of the child. It should be kept in mind that errors due to structural defects cannot be corrected through speech therapy unless the structural deformity is corrected. Also, the structural correction should invariably be followed with speech therapy to correct the functioning/production of speech sounds. Appropriate feedback (using multiple modalities such as auditory, visual, tactile, etc.) is extremely important in the management of articulation and resonance disorders.
Elements of oromotor therapy (such as blowing, sucking, whistling, and electrical stimulation) are not useful in facilitating the correct production of speech sounds. It has been demonstrated that there are significant differences in the velopharyngeal closure patterns of speech and nonspeech activities. Furthermore, because individuals with cleft lip and palate have a structural deformity and not a muscle weakness, oromotor exercises should be avoided in this population.