Key Points
Question
Does secondary speech surgery improve velopharyngeal insufficiency (VPI)-specific quality of life (QOL), as measured with the VELO instrument?
Findings
In this prospective study of 29 children and young adults, VELO scores were statistically significantly improved after speech surgery. The severity of perceptual speech impairment was significantly correlated with the VELO scores.
Meaning
The VELO instrument is further validated with inclusion of pharyngeal flap surgery, demonstrating that speech surgery improves VPI-specific QOL.
This study uses the Velopharyngeal Insufficiency Effects on Life Outcomes instrument to assess the association of improved speech with quality of life in patients who underwent secondary speech surgery.
Abstract
Importance
Patients with cleft palate and other causes of velopharyngeal insufficiency (VPI) suffer adverse effects on social interactions and communication. Measurement of these patient-reported outcomes is needed to help guide surgical and nonsurgical care.
Objectives
To further validate the VPI Effects on Life Outcomes (VELO) instrument, measure the change in quality of life (QOL) after speech surgery, and test the association of change in speech with change in QOL.
Design, Setting, and Participants
Prospective descriptive cohort including children and young adults undergoing speech surgery for VPI in a tertiary academic center. Participants completed the validated VELO instrument before and after surgical treatment.
Main Outcomes and Measures
The main outcome measures were preoperative and postoperative VELO scores and the perceptual speech assessment of speech intelligibility. The VELO scores are divided into subscale domains. Changes in VELO after surgery were analyzed using linear regression models. VELO scores were analyzed as a function of speech intelligibility adjusting for age and cleft type. The correlation between speech intelligibility rating and VELO scores was estimated using the polyserial correlation.
Results
Twenty-nine patients (13 males and 16 females) were included. Mean (SD) age was 7.9 (4.1) years (range, 4-20 years). Pharyngeal flap was used in 14 (48%) cases, Furlow palatoplasty in 12 (41%), and sphincter pharyngoplasty in 1 (3%). The mean (SD) preoperative speech intelligibility rating was 1.71 (1.08), which decreased postoperatively to 0.79 (0.93) in 24 patients who completed protocol (P < .01). The VELO scores improved after surgery (P<.001) as did most subscale scores. Caregiver impact did not change after surgery (P = .36). Speech Intelligibility was correlated with preoperative and postoperative total VELO score (P < .01) and to preoperative subscale domains (situational difficulty [VELO-SiD, P = .005] and perception by others [VELO-PO, P = .05]) and postoperative subscale domains (VELO-SiD [P = .03], VELO-PO [P = .003]). Neither the VELO total nor subscale score change after surgery was correlated with change in speech intelligibility.
Conclusions and Relevance
Speech surgery improves VPI-specific quality of life. We confirmed validation in a population of untreated patients with VPI and included pharyngeal flap surgery, which had not previously been included in validation studies. The VELO instrument provides patient-specific outcomes, which allows a broader understanding of the social, emotional, and physical effects of VPI.
Level of Evidence
2.
Introduction
Velopharyngeal insufficiency (VPI) is a disorder that results in improper closing of the soft palate against the pharyngeal wall during speech. This is one aspect of the broader term velopharyngeal dysfunction (VPD). Velopharyngeal insufficiency allows air to escape from the nose during speech, resulting in a hypernasal speech that is difficult to understand. The causes of VPI can be multifactorial but often include some neuromuscular dysfunction or structural (anatomic) abnormality in the velum. Any child with cleft palate is at risk for VPI owing to the structural abnormalities of the palate. The cleft affects the musculature responsible for coordinated closure during speech and swallowing. Even after surgical repair, residual deficits often remain. In fact, the most common cause of VPI is a history of cleft palate or submucous clefting.
The most appropriate treatment of children with orofacial clefts is with a multidisciplinary cleft team, as supported by the American Cleft Palate Association. Team members include speech/language pathologists, (facial) plastic surgeons, otolaryngologists, audiologists, nurses, social workers, dentists, orthodontists, geneticists, pediatricians, and oral surgeons. Children born with orofacial clefts require multiple surgical procedures, complex medical treatments, and long-term speech therapy. Facial plastic surgeons not only repair the cleft lip and palate deformities but also treat the functional aspects of speech over the course of the child’s development. Surgical therapy (eg, palatoplasty) is performed typically around age 10-14 months in children with cleft palate. The goal of surgery is to provide a more normal anatomic framework by the time toddlers are developing speech. Many children can develop near normal speech patterns following palatoplasty with adjunctive speech therapy. However, even after repair, 20% to 30% of children with cleft palate will have persistent VPI.
Correcting cleft speech is very important for the child’s future ability to live independently and to participate fully in society. Children with orofacial clefts have been shown to have greater behavioral problems and overall social and academic problems, increased symptoms of depression, and are more likely to be teased. A recent expert consortium has called for quality of life (QOL) studies as a priority for future research for orofacial clefts. Cost-effectiveness research has demonstrated that exorbitant health care costs are spent on immediate and long-term health (eg, VPI) and socioeconomic well-being in this patient population.
Most studies focusing on children with orofacial clefts make their argument for surgical therapy using objective measures, such as anatomic measurements, photodocumentation, morbidity, and mortality. However, there are few studies using validated instruments that assess if surgical, medical, and speech therapy provide positive outcomes in these children’s QOL. Even more rare are studies that compare improved objective measures of cleft-related speech with improved QOL.
Several QOL questionnaires that address this issue have been developed over the years. Eckstein et al investigated how these questionnaires were validated in the cleft lip and palate population. A paucity of validated questionnaires related to cleft lip and palate was discovered, especially related to speech. Prior investigations have demonstrated that administration of speech surveys provides a reliable means of determining speech-related QOL. The VPI Effects on Life (VELO) questionnaire is an instrument that was developed to capture the effects of VPI on QOL in children and young adults with VPI. It has been shown to correlate with prior validated speech-specific QOL surveys, as well as with patient-reported and objectively measured outcomes. This tool adds a patient-oriented, subjective outcome to the objective outcomes that our team currently follows in treating children with VPI before and after speech surgery. The previous validation, though, used a heterogeneous sample of VPI patients, some who had previously had VPI surgery and some who had not. The previous studies on improving VPI-specific QOL were done at a center that exclusively used Furlow Palatoplasty and sphincter pharyngoplasty.
While previous studies have helped to describe the change in VELO for categories of parent-reported change, interpreting a change of 20 points remains elusive. Clinicians have more clinical understanding of categorical change in perceptual speech analysis ratings. The relationship of change in perceptual speech ratings and change in VELO has yet to be defined. Our aims were to add to the growing body of literature on how surgery, in combination with speech therapy, relates to each patient’s QOL in the setting of VPI surgery.
We sought to measure the QOL changes in children and young adults with VPI after speech surgery. The objectives of the project were to confirm the previous validation of the VELO at a different institution, to measure the change in QOL after speech surgery, and examine the relationship between VELO scores and the perceptual speech rating by the speech language pathologist (at baseline and postoperatively). Our research questions were formed as follows: (1) to test for improvement in VPI-specific QOL using the VELO instrument in patients undergoing speech surgery (primarily pharyngeal flap); (2) test the association of preoperative and postoperative VELO total (and subscales) with the preoperative and postoperative speech ratings by perceptual speech assessment; and (3) test the association of the change in VELO with change in speech intelligibility.
Methods
After obtaining University of California Davis institutional review board approval, we began prospective enrollment of all patients aged 3 to 21 years with VPI who underwent speech surgery at the University of California Davis Cleft and Craniofacial Team between December 2013 and July 2016. Informed consent was obtained from parents for children younger than 18 years, and from the patient if aged 18 years or older. Participant inclusion was voluntary and no compensation was provided for their participation. Exclusion criteria included severe intellectual disability or speech surgery within 6 months prior to enrollment. Data points included: age, cleft type, and standardized preoperative and postoperative perceptual speech assessment. Three surgeons on the cleft panel participated in contribution of their patients.
Patient-Reported Outcomes
The VELO instrument is a VPI-specific quality-of-life instrument. The VELO includes a 26-item parent version and 23-item youth version. The parent version was given to all parents, and the youth version was given to the patient if he/she was older than 8 years. The response format is a 5-point Likert-type scale ranging from never (0) to almost always (4). The VELO is divided into 5 subscales:
Speech limitation (VELO-SL),
Swallow problems (VELO-SP),
Situational difficulty (VELO-SiD),
Emotional impact (VELO-EI), and
Perception by others (VELO-PO).
Caregiver impact (VELO-CI) was measured by an additional 3 parent questions. Surveys were given to the patient or their parent prior to speech surgery and again at their 3-month postoperative speech evaluation.
Speech Assessment
Standardized preoperative perceptual speech assessment and velopharyngeal dysfunction assessment with nasopharyngoscopy were documented by the cleft team speech-language pathologist and surgeon. While surgery addresses hypernasality, speech intelligibility was used as our primary speech measure because it has been shown to have a higher correlation with VPI-specific QOL and may be a better overall measure of cleft speech-related problems. Speech intelligibility impairment was graded by assessing the nasal air emission and resonance severity using a validated scale: 0, within acceptable limits; 1, mild; 2, moderate; 3, severe. This was completed at baseline and 3 months after surgical treatment.
The velopharyngeal closure pattern was assessed with standardized nasopharyngeal endoscopy and the treatment plan was jointly formulated. At our institution, the speech surgical plan is developed by the consistent, interdisciplinary cleft team evaluation which includes, but is not limited to the review of the following factors: perceptual speech evaluation, velopharyngeal closure pattern seen on nasopharyngeal endoscopic examination, previous surgical treatments, palatal length, comorbidities, and airway obstruction symptoms.
The velopharyngeal closure pattern and size of velopharyngeal gap are 2 objective factors that guided surgical options, which include: (1) pharyngeal flap, (2) Furlow palatoplasty (double opposing z-plasty), and (3) sphincter pharyngoplasty. In our cleft team, the pharyngeal flap is typically used for large central gap with sagittal closure patterns and adequate lateral wall movement. A Furlow palatoplasty is used when a small central gap is noted, especially when a notched soft palate is seen on endoscopy, which indicates levator veli palatini malpositioning. A sphincter pharyngoplasty is chosen when a primarily coronal closure pattern is noted and levator veli palatini is transversely oriented.
Statistical Analysis
The 3 hypotheses were tested using linear regression modeling to test the relationship while controlling for a priori hypothesized confounders. Change from baseline (preoperative) total VELO score (without VELO-Caregiver Impact questions) and VELO subscale scores were analyzed using a linear model, adjusting for baseline speech intelligibility rating, age, and cleft type as covariates. The VELO total and subscale scores were likewise analyzed as a function of speech intelligibility rating using linear models, adjusting for age and cleft type by including these as covariates. The change in speech intelligibility was estimated using the paired student t test. The correlation between VELO subscale/total scores and speech intelligibility was estimated using the polyserial correlation, a measure of correlation between a continuous variable and an ordered categorical variable. Analyses were conducted using the statistical software environment R (version 3.2.5, R Foundation).
Results
Patient Demographics
After exclusion criteria, 29 patients with VPI were enrolled and completed the VELO instrument before surgery. Three parents elected against surgery. Among the 26 who had VPI surgery, 24 patients (92%) completed surgery and the postoperative VELO survey with 2 not included because 1 moved away before the surgery and 1 after the surgery.
Table 1 shows demographic and surgery characteristics for all patients. Speech surgery consisted of pharyngeal flap in 14 patients (51%), Furlow palatoplasty in 12 (44%), and sphincter pharyngoplasty in 1 patient (3%). The mean (SD) age was 7.9 (4.1) years (range, 4-20 years.), including 13 (45%) males and 16 (55%) females. Most (23 patients, 80%) had orofacial clefts, whereas 6 (20%) patients had VPI from non-cleft etiology. Most patients with clefts had isolated cleft palate (n = 6) or submucous clefting (n = 7), (total, 43.3%), while 5 (16.7%) patients had unilateral cleft lip and palate, and 5 (16.7%) patients had bilateral cleft lip and palate. Three (10%) patients had 22q.11 deletion syndrome, whereas 3 (10%) other patients had velar dysfunction of unknown etiology.
Table 1. Demographic and Surgery Characteristics in 29 Patients.
| Descriptor | Patients, No. (%) |
|---|---|
| Age, y | |
| Mean (SD) | 7.9 (4.1) |
| Median (range) | 6 (4-20) |
| Sex | |
| Male | 13 (44) |
| Female | 16 (55) |
| Diagnosis | |
| Isolated cleft palate | 13 (43.3) |
| Unilateral cleft lip-palate | 5 (16.7) |
| Bilateral cleft lip-palate | 5 (16.7) |
| 22q.11 deletion | 3 (10) |
| Unknown etiology | 3 (10) |
| Velopharyngeal gap | |
| Normal | 0 (0) |
| Mild | 16 (55.1) |
| Moderate | 8 (27.6) |
| Severe | 2 (6.8) |
| Unable to perform | 3 (10.3) |
| Type of surgery | |
| Furlow palatoplasty | 12 (44) |
| Pharyngeal flap | 14 (51) |
| Sphincter | 1 (3) |
Speech Outcomes
Complete presurgery and postsurgery perceptual speech data sets were available for 24 patients. The mean (SD) baseline speech intelligibility rating (0-3 scale) was 1.71 (1.08), which decreased to 0.79 (0.93) (P < .01). Only 2 patients remained in the severe category postoperatively. The number of patients in the normal category increased from 4 (16.7%) before surgical treatment to 11 (36.7%) after, whereas the number of patients in the mild category increased from 6 (25.0%) preoperatively, to 7 (23.3%) postoperatively. The number of patients in the moderate group improved from 7 (29.1%) before surgical treatment to 4 (13.3%) after, and the total in the severe category improved from 7 (29.1%) preoperatively to 2 patients (6.7%) after the intervention. All patients but 1 had either a decrease (improvement) or no change in speech intelligibility impairment after surgery. The 4 patients rated normal had intermittent nasal air emission and hypernasality amenable to speech surgery, but not poor intelligibility on examination.
Patient-Centered Outcomes
The results of the linear model for change from baseline in VELO total and each subscale domain, adjusting for baseline VELO score, age, and cleft type showed that total VELO (without VELO-CI questions) scores increased significantly after surgery by a mean of 19.6 points (range, 13.6-25.6; P < .001). All subscale domains also improved except caregiver impact. The change from baseline in VELO subscale domains from linear modeling are presented as the mean with (95% CIs). The VELO subscale scores change estimate were as follows: speech limitation, 19.5 (95% CI, 9.8 to 29.3; P < .001); swallow problems 6.7 (95% CI, 2.8 to 10.7; P = .002); situational difficulty, 26.2 (95% CI, 15.3 to 37.1; P < .001); emotional impact, 22.1 (95% CI, 14.1 to 30.1; P<.001); perception by others, 16.3 (95% CI, 9.4 to 23.2; P<.001). Caregiver impact did not change after surgery estimated change 15.2 (95% CI, −20.7 to 51.2; P = .36). These are demonstrated in Table 2.
Table 2. VELO Score and Subscale Domains Scores Shown Presurgery and Postsurgery.
| VELO Domain | Presurgery (n = 29) | Postsurgery (n = 24) | Change in VELO (n = 24)a |
|---|---|---|---|
| VELO total | |||
| Mean (SD) | 58.4 (18.6) | 77.7 (13.1) | 19.6 (13.4) |
| Median (range) | 57.6 (13 to 93.5) | 81 (50 to 98.9) | 18.5 (0.2 to 60.9) |
| Speech limitations | |||
| Mean (SD) | 46.4 (10.7 to 92.9) | 64.3(32.1 to 96.4) | 21.5 (18.1) |
| Median (range) | 43.7 (21.4) | 64.3 (18.8) | 17.9 (−10.7 to −50) |
| Swallow problems | |||
| Mean (SD) | 89.7 (14.7) | 95.8 (6.5) | 7.3 (14.4) |
| Median (range) | 100 (41.7 to 100) | 100 (83.3 to 100) | 0 (−8.3 to −58.3) |
| Situational difficulty | |||
| Mean (SD) | 40.9 (24.1) | 68.1 (22.1) | 26.9 (18.5) |
| Median (range) | 40 (5 to 95) | 70 (20 to 100) | 27.5 (0 to 70) |
| Emotional impact | |||
| Mean (SD) | 64.9 (27.3) | 85.9 (15.8) | 21.6 (21.4) |
| Median (range) | 62.5 (0 to 100) | 93.8 (50 to 100) | 15.6 (0 to 75) |
| Perception by others | |||
| Mean (SD) | 77.2 (23.9) | 91.4 (10.9) | 14.8 (24.9) |
| Median (range) | 81.2 (18.8 to 100) | 96.9 (68.8 to 100) | 12.5 (−25 to 75) |
| Caregiver impact | |||
| No. | 18 | 13 | 13 |
| Mean (SD) | 54.6 (17.9) | 73.7 (13.1) | 21.2 (23.2) |
| Median (range) | 54.2 (13 to 93.5) | 75 (33.3 to 100) | 16.7 (−33.3 to 58.3) |
For hypothetical patient with baseline score and age equal to mean and cleft type 1.
Table 3 shows the polyserial correlation between VELO scores and speech intelligibility, with P values from a linear model for VELO score by speech intelligibility, age, and cleft type. Both preoperative and postoperative total score were significantly correlated with speech intelligibility. The Figure shows boxplots of preoperative and postoperative VELO scores by presurgery speech intelligibility, respectively. Postsurgery, the VELO-SL, VELO-SiD, VELO-PO subscales and the total score are significantly correlated with speech intelligibility.
Table 3. Correlation Between VELO Subscales and Speech Intelligibility.
| Variable | Presurgery Polyserial Correlation (95% CI) | Presurgery P Value | Postsurgery Polyserial Correlation (95% CI) | Postsurgery P Value | Changes in VELO Polyserial Correlation (95% CI) | Changes in VELO P Value |
|---|---|---|---|---|---|---|
| VELO total | 0.71 (0.51 to 0.91) | .008 | −0.64 (−0.88 to −0.40) | .006 | −0.39 (−0.76 to −0.02) | .07 |
| Speech limitation | −0.49 (−.78 to −0.20) | .24 | −0.61 (−0.86 to −0.36) | .02 | −0.03 (−0.48 to 0.42) | .73 |
| Swallow problems | −0.38 (−0.73 to −0.03) | .16 | −0.11 (−0.54 to 0.32) | .53 | 0.01 (−0.46 to 0.44) | .92 |
| Situational difficulty | −0.7 (−0.88 to −0.52) | .005 | −0.54 (−0.83 to −0.25) | .03 | −0.34 (−0.71 to 0.03) | .14 |
| Emotional impact | −0.65 (−0.87 to −0.43) | .01 | −0.46 (−0.79 to −0.02) | .08 | −0.46 (−0.79 to −0.13) | .06 |
| Perception by others | −0.58 (−0.83 to −0.33) | .05 | −0.58 (−0.85 to −0.31) | .003 | −0.44 (−0.79 to −0.09) | .10 |
| Caregiver impact | −0.34 (−0.79 to 0.11) | .18 | −0.39 (−0.90 to 0.12) | .16 | −0.11 (−0.70 to 0.48) | .23 |
Figure. Preoperative and Postoperative Speech Intelligibility.
The boxes indicate the 25th to 75th percentile with bold lines marking the median. The whiskers show the smallest and largest observations lying within 1.5 interquartile ranges of the box edges. Observations outside this range are indicated by an open circle. A, Association of preoperative speech intelligibility with quality of life. B, Association of postoperative speech intelligibility with quality of life.
Table 3 (right column) also shows the polyserial correlation between changes in VELO scores and changes in speech intelligibility, with P values from a linear model for change in VELO score by change in intelligibility, age, and cleft type. A relationship between the amount of change in any of the total VELO or subscale scores with the change in speech intelligibility was not found.
Discussion
The results of this QOL study are consistent with and extend from previous reports on the effectiveness of speech surgery to improve the QOL in children with orofacial clefts, further confirming the previous validation of the VELO at a different institution. The applicability of the VELO instrument as a patient-reported outcome for VPI is further supported by finding that that VPI-specific QOL was improved after speech surgery.
Further discussion is warranted on the correlation between the preoperative and postoperative VELO scores to the speech language pathologist’s perceptual speech assessment, although only 2 subscales of the VELO (VELO-SiD and VELO-PO) were significantly associated with the measured speech rating. Previous validation analyses of the VELO instrument used a convenience sample of patients with partially treated and untreated VPI. The analysis here extends on the previous validation analyses in a cohort of VPI patients before and after speech surgery. The associations shown herein help provide further evidence of the relationship between the VELO scores and speech ratings, further validating the QOL instrument.
The speech intelligibility ratings were chosen after careful consideration as the measurement of the severity of the child’s speech problem. There are several difficulties with using this possibly flawed but ultimately best available metric. The perceptual speech assessment includes items such as hypernasal resonance, nasal air emission, and speech acceptability. Four patients had normal speech intelligibility but significant nasal air emission that de facto could not improve from normal after surgery. In addition, a child with severely affected speech intelligibility may benefit more from surgery than a child with a mild preoperative rating. In response to this possibility, we are collecting further data to test the hypothesis that a dichotomized category could be developed, such as adequate and inadequate speech intelligibility.
The VELO QOL scores in this study effectively measured VPI-specific QOL and a correlation to the cleft team’s speech language pathologist’s speech rating. The parental VELO instrument includes 3 questions in the VELO-CI domain, which was the exception. The relationship between the parent perception of the child’s QOL and the severity of the child’s speech intelligibility was not detected. The arduous task of developing effective domain survey questions that capture the caregiver impact is difficult owing to the complexity of the effect of speech and communication on a child’s QOL. The parental perspective may also include other aspects, such as perceptions, inherent bias, or assignment of QOL changes based on situations not related to the child’s speech. The lack of correlation may also be owing to the limited sample size for VELO-CI domain (13 parents of children aged <8 years given the VELO-CI questions). Future outcomes are being collected from both parents and youth to better answer this question.
Strengths and Limitations
These data must be interpreted in the context of the study design. Completion of the study was completed by 82% of the patients owing to the parents deciding against surgery or moving away. Of those having surgery, more than 90% had follow-up, limiting the potential for bias. Also, as stated above, we relied on speech improvement assessment by our own cleft team members and the ratings may be biased by the knowledge that the child had surgery. Ideally, we can establish blinded evaluators to further validate our perceived improvement. In addition, there is no control group in this study of patients that did not undergo speech surgery. A recently published study that compared patients who underwent surgery with those who did not demonstrate similar point estimate improvement with surgery and a small improvement without surgery.
The treatment effectiveness identified in this study was owing, in large part, to pharyngeal flap surgery. The point estimate change in VELO in participants was similar to that found in previous studies. In this last study the change was from mean 55 preoperatively to mean 76 postoperatively. The 3 primary surgical treatments for VPI include Furlow palatoplasty, pharyngeal flap, and sphincter pharyngoplasty. Previous studies showing improvement in QOL with speech surgery did not include pharyngeal flap in their treatments. This study helps show the improvement in VPI-specific QOL with Furlow palatoplasty and pharyngeal flap surgery.
The VELO QOL instrument can be applied in future patient-reported outcome assessments of these patients. Examples of ongoing and upcoming studies include: (1) testing the factors that the VELO subscales best measure, (2) comparing VPI treatment paradigms between institutions, (3) validating a Spanish version of the VELO, and (4) testing the association of speech surgery success with speech therapy availability. This last research project extends from testing the effect of VPI surgery on QOL (as shown in this study) to include other factors in the entire care delivery process, such as compliance with follow-up, and availability of speech therapy. Currently the senior author is using the VELO instrument as a measure of the impact of augmenting speech therapy using iPad speech games for children in remote areas with obstacles to speech care.
Conclusions
Speech surgery improves the VPI-specific QOL. We confirmed validation of the VELO QOL instrument in a population of untreated VPI patients and included pharyngeal flap surgery, which has not been previously reported. The severity of speech was correlated with the VELO scores. VELO provides patient-specific outcomes, which allows a broader understanding of the social, emotional, and physical effects of VPI.
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