Thomas W. Guyette

Changes in Speech following Maxillary Distraction Osteogenesis

OBJECTIVE The purpose of this study was to describe changes in articulation and velopharyngeal function following maxillary distraction osteogenesis. DESIGN This is a descriptive, post hoc clinical report comparing the performance of patients before and after maxillary distraction. The independent variable was maxillary distraction while the dependent variables were resonance, articulation errors, and velopharyngeal function. SETTING The data were collected at a tertiary health care center in Chicago. PATIENTS The data from pre- and postoperative evaluations of 18 maxillary distraction patients were used. OUTCOME MEASURES The outcome measures were severity of hypernasality and hyponasality, velopharyngeal orifice size as estimated using the pressure-flow technique, and number and type of articulation errors. RESULTS At the long-term follow-up, 16.7% exhibited a significant increase in hypernasality. Seventy-five percent of patients with preoperative hyponasality experienced improved nasal resonance. Articulation improved in 67% of patients by the 1-year follow-up. CONCLUSIONS In a predominately cleft palate population, the risk for velopharyngeal insufficiency following maxillary distraction is similar to the risk observed in Le Fort I maxillary advancement. Patients being considered for maxillary distraction surgery should receive pre- and postoperative speech evaluations and be counseled about risks for changes in their speech.

Evaluation of cleft palate speech

Children born with palatal clefts are at risk for speech/language delay and speech problems related to palatal insufficiency. These individuals require regular speech evaluations, starting in the first year of life and often continuing into adulthood. The primary role of the speech pathologist on the cleft palate/craniofacial team is to evaluate whether deviations in oral cavity structures, such as the velopharynx, negatively impact speech production. This article focuses on the assessment of velopharyngeal function before and after palatal surgery.

Pressure-flow measurements for selected oral and nasal sound segments produced by normal adults.

Pressure-flow data are often used to provide information about the adequacy of velopharyngeal valving for speech. However, there is limited information available concerning simultaneous pressure-flow measurements for oral and nasal sound segments produced by normal speakers. This study provides normative pressure, flow, and velopharyngeal orifice area measurements for selected oral and nasal sound segments produced by 10 male and 10 female adult speakers. An aerodynamic categorization scheme of velopharyngeal function, including one typical category and three atypical categories (open, closed, and mixed) is proposed.

Pressure-flow differences in performance during production of the CV syllables/pi/ and /pa/

Inconsistencies in velopharyngeal function were observed to have been reported in pressure-flow reports. This article introduces our findings from a sample of pressure-flow records and discusses possible implications for management. A retrospective review of the pressure-flow records for 51 patients was completed. All patients had been evaluated at the Craniofacial Center, University of Illinois at Chicago. Records were selected based on the following criteria: patients were referred for evaluation of velopharyngeal function and had no secondary surgeries on the velopharyngeal mechanism, no fistulae, no neurologic disorders, and no compensatory articulations. At the time of testing, patients ranged in age from 4 to 38 years with most being under 18 years of age. Velopharyngeal orifice areas were obtained using the pressure-flow technique during repeated CV syllables, including /pi/ and /pa/. Our results show that 8 of 51 patients exhibited a specific type of inconsistent velopharyngeal function (i.e., they exhibited velopharyngeal closing during /pa/ repetitions, but had openings during /pi/ repetitions). The reverse finding was not observed among any of the 51 patients. We concluded that the velopharyngeal incompetence observed during utterances involving /i/ may have been due to the downward pull on the palate of the palatoglossus muscle, which could not be counteracted by the already maximized levator activity in borderline patients.

Laryngeal airway resistance in cleft palate children with complete and incomplete velopharyngeal closure.

OBJECTIVE This study investigated the effect of velopharyngeal insufficiency on aerodynamic measures of laryngeal function in children with cleft palate. DESIGN Data were analyzed using analysis of covariance. The independent variable was velopharyngeal closure, and the dependent variables were laryngeal resistance, laryngeal airflow, and transglottal pressure. Age and gender were covariates. SETTING The data were collected at The Craniofacial Center, University of Illinois, a tertiary health care center located in Chicago. PATIENTS Thirty-six children with cleft palate were recruited from among the patients at The Craniofacial Center. Ten children with velopharyngeal areas >5 mm2 during oral speech were placed in the incomplete closure group, while 26 children with areas <1 mm2 were placed in the complete closure group. OUTCOME MEASURES The three dependent variables (transglottal pressure, transglottal airflow, and laryngeal resistance) were measured. RESULTS Laryngeal resistance and transglottal pressure were significantly higher, and transglottal airflow was significantly lower in the group with complete closure. CONCLUSIONS In summary, cleft palate patients with complete velopharyngeal closure exhibited higher laryngeal resistances than those with incomplete closure.

Changes in speech following unilateral mandibular distraction osteogenesis in patients with hemifacial microsomia.

OBJECTIVE The purpose of this study was to describe changes in articulation, resonance, and velopharyngeal function following mandibular distraction osteogenesis. DESIGN This is a descriptive, post hoc study comparing the performance of patients on measures of articulation, resonance, and velopharyngeal function before and after mandibular distraction. SETTING The data were collected at a tertiary health care center located in Chicago. PATIENTS The clinical data from preoperative and postoperative evaluations of seven mandibular distraction patients were used. OUTCOME MEASURES The outcome measures were number of articulation errors, severity of hypernasality and audible nasal emission, and velopharyngeal orifice size as estimated using the pressure-flow technique. RESULTS Immediately after distraction, 28% (2/7) experienced a temporary deterioration in articulation and 42% (3/7) experienced a deterioration in nasal resonance. But by the long-term follow-up evaluation, all had returned to their preoperative levels. Pressure-flow test results generally support the perceptual findings. CONCLUSIONS Patients being considered for mandibular distraction surgery should receive preoperative and postoperative speech evaluations and be counseled about risks for changes in their speech following surgery.

Component Approach for Partitioning Nasal Airway Resistance: Pharyngeal Flap Case Studies

Individuals with craniofacial anomalies often have nasal cavity and/or velopharyngeal constriction. The purpose of this clinical report was to illustrate a technique for partitioning nasal airway resistance into its nasal cavity and velopharyngeal components. This information would be helpful in determining intervention to reduce high nasal airway resistance as well as in providing information about the outcome of corrective procedures to establish velopharyngeal competence for speech. Data from two pharyngeal flap patients seen before and after surgery were utilized in this illustration. These case studies illustrate the usefulness of component resistance measures in quantifying nasal airway patency before and after corrective surgery for velopharyngeal function.

Partitioning Nasal Airway Resistance in Normal Adults

A rhinomanometric method that partitions nasal airway resistance into its nasal cavity and velopharyngeal components is described. Nasal cavity resistance, velopharyngeal resistance and total nasal airway resistance is reported for 20 normal subjects (10 women and 10 men). During expiration, mean nasal cavity resistance for women (1.52 cm H2O/[liters per second] L/s) was 76.3% and mean velopharyngeal resistance (.64 cm H2O/L/s) constituted 23.7% of the total nasal airway resistance. For men, mean nasal cavity resistance (1.50 cm H2O/L/S) made up 70.2% and mean velopharyngeal resistance (.85 cm H2O/L/S) was 29.8% of the total nasal airway resistance. During inspiration, the mean nasal cavity resistance for women (1.47 cm H2O/L/s) was 75.8% and mean velopharyngeal resistance (.44 cm H2O/L/s) was 24.2% of total nasal airway resistance. For men, mean nasal cavity resistance (1.30 cm H2O/L/s) constituted 73.9% and mean velopharyngeal resistance (.83 cm H2O/L/s) made up 26.1% of total nasal airway resistance. The importance of this method in clinical practice is discussed.

Effect of septal perforations on measures of nasal resistance

OBJECTIVE The purpose of this investigation was to determine the effect of septal perforations on posterior and anterior rhinomanometric measures of nasal resistance in an analog model. DESIGN The data were analyzed using a repeated-measures ANOVA. Nasal resistance was the dependent variable, while type of rhinomanometry, septal perforation size, and position of resistance (proximal vs. distal) were nominal scale independent variables. PARTICIPANTS The analog model used in this study was similar to that described by Warren and Devereux (1966), except that the nasal cavities of the model were modified to create septal perforations. OUTCOME MEASURES The main dependent measure was nasal resistance. RESULTS An Important finding of this investigation was that septal perforations resulted in large differences (> 3 cm H2O/L/sec) between posterior and anterior nasal resistance values in the bilateral proximal resistor condition. CONCLUSIONS Anterior rhinomanometry may underestimate true nasal resistance when a septal perforation is present, because the septal perforation prevents accurate measurement of nasopharyngeal pressure. Posterior rhinomanometric measures should accurately reflect nasal resistance despite septal perforations, because the perforation does not invalidate the estimate of nasopharyngeal pressure.