Impact of Maxillary Advancement on Speech and Velopharyngeal Function in Patients with Cleft Lip and Palate

Does Distraction Lower Risk of VPI Compared to Conventional Maxillary Advancement? A Retrospective Cohort Study of Adolescents with Cleft Palate

OBJECTIVE

To determine whether method of maxillary advancement in adolescents with cleft palate with or without cleft lip (CP ± L) influences post-operative velopharyngeal function.

DESIGN

Retrospective cohort.

SETTING

Pediatric Tertiary Care Hospital.

PARTICIPANTS

One hundred and ninety-nine patients with CP ± L after LeFort I osteotomy for maxillary advancement at our institution between January 2007 and June 2019.

INTERVENTIONS

LeFort I osteotomy via distraction osteogenesis (DO) or conventional osteotomy (CO).

MAIN OUTCOME MEASURES

Patients who underwent DO or CO were compared for the presence of new velopharyngeal insufficiency (VPI), as measured by perceptual rating by a craniofacial speech-language pathologist.

Of the 199 patients who underwent maxillary advancement, 126 were available for analysis. The DO group was younger, male, and had more severe maxillary hypoplasia. Following surgery, 17/41 (41.5%) of the DO group had new VPI, compared to just 23/85 (27.1%) of the CO group. After adjusting for cleft type and predicted maxillary advancement, however, there was not sufficient evidence to reject the null hypothesis of no difference in risk of post-operative VPI between the two surgical groups (prevalence ratio [PR] 1.40, 95% CI 0.68-2.90). Increased prevalence of VPI after DO versus CO was primarily observed among patients with a pre-operative velopharyngeal need ratio < 0.8 (PR = 2.01, 95% CI 0.79-5.10) and patients with normal velopharyngeal function pre-operatively (PR = 2.86, 95% CI 0.96-8.50).

Our results suggest an increased rather than decreased risk of VPI following DO relative to CO. This association is primarily seen among those with a smaller velopharyngeal ratio or perceptually normal velopharyngeal function pre-operatively.

Long-term speech outcome after anterior distraction osteogenesis of the maxilla in patients with cleft lip and palate

Advancement of the maxilla may increase the distance between the soft palate and the posterior pharyngeal wall in patients with cleft lip and palate, implying a risk of velopharyngeal dysfunction. The aim was to evaluate long-term speech outcome in a consecutive series of patients treated with distraction osteogenesis (DO). Fourteen out of the 16 patients agreed to participate. A long-term speech follow-up was performed 1.5 to 13.5 years after DO. For two participants, audio recordings before DO were missing, and for another one, it was incomplete. The percentage of consonants correct (PCC) based on phonetic transcription and perceived velopharyngeal competence rated on a three-point scale were assessed before and after DO by three independent judges, based on audio recordings of reading of standardised sentences. Also, the participants were asked how they perceived their speech after DO. Changes in PCC were insignificant. Four participants perceived deteriorated speech related to DO. In two cases, the subjective deterioration did not correlate to results from perceptual assessment. In two others, the subjective deterioration correlated with the perceptual assessment, and the velopharyngeal function was judged as being incompetent after DO. After secondary velopharyngeal surgery, velopharyngeal function improved to competent in one case and marginally incompetent in the other. The results need to be interpreted with caution due to methodological limitations but indicate that some patients develop deteriorated velopharyngeal function after DO. The impact on articulation needs to be further explored. It is important that patients are informed before treatment of the risk of velopharyngeal dysfunction after DO.

How differences in anatomy and physiology and other aetiology affect the way we label and describe speech in individuals with cleft lip and palate

BACKGROUND

Speech in individuals with cleft lip and/or palate (CLP) is a complex myriad of presenting symptoms. It is uniquely associated with the structural difference of velopharyngeal insufficiency (VPI), together with a wide and heterogeneous range of other aetiologies which often co-occur. The nature of the speech sound disorder (SSD) including VPI may also change over the course of an individual's care pathway. Differences in terminology and approaches to analysis are currently used, resulting in confusion internationally. Additionally, current diagnostic labels and classification systems in SSD do not capture the complexity and full nature of speech characteristics in CLP.

AIMS

This paper aims to explore the different aetiologies of cleft palate/VPI speech and to relate aetiology with speech characteristic(s). In so doing, it attempts to unravel the different terminology used in the field, describing commonalities and differences, and identifying overlaps with the speech summary patterns used in the United Kingdom and elsewhere. The paper also aims to explore the applicability of current diagnostic labels and classification systems in the non-cleft SSD literature and illustrate certain implications for speech intervention in CLP.

METHODS AND PROCEDURES

The different aetiologies were identified from the literature and mapped onto cleft palate/VPI speech characteristics. Different terminology and approaches to analysis are defined and overlaps described. The applicability of current classification systems in SSD is discussed including additional diagnostic labels proposed in the field.

OUTCOMES AND RESULTS

Aetiologies of cleft palate/VPI speech identified include developmental (cognitive-linguistic), middle ear disease and fluctuating hearing loss, altered oral structure, abnormal facial growth, VPI-structural (abnormal palate muscle) and VPI-iatrogenic (maxillary advancement surgery). There are four main terminologies used to describe cleft palate/VPI speech: active/passive and compensatory/obligatory, which overlap with the four categories used in the UK speech summary patterns: anterior oral cleft speech characteristics (CSCs), posterior oral CSCs, non-oral CSCs and passive CSCs, although not directly comparable. Current classification systems in non-cleft SSD do not sufficiently capture the full nature and complexity of cleft palate/VPI speech.

CONCLUSIONS AND IMPLICATIONS

Our attempt at identifying the heterogeneous range of aetiologies provides clinicians with a better understanding of cleft palate/VPI speech to inform the management pathway and the nature and type of speech intervention required. We hope that the unravelling of the different terminology in relation to the UK speech summary patterns, and those used elsewhere, reduces confusion and provides more clarity for clinicians in the field. Diagnostic labels and classification require international agreement.

WHAT THIS PAPER ADDS

What is already known on the subject Speech associated with cleft palate/velopharyngeal insufficiency (VPI) is a complex myriad of speech characteristics with a wide and heterogeneous range of aetiologies. Different terminology and speech summary patterns are used to describe the speech characteristics. The traditional classification of cleft palate/VPI speech is Articulation Disorder, although evidence is building for Phonological Disorder and contrastive approaches in cleft speech intervention. What this paper adds to existing knowledge This paper explores the range of aetiologies of cleft palate/VPI speech (e.g., altered oral structure, abnormal facial growth, abnormal palate muscle and iatrogenic aetiologies) and attempts to relate aetiology with speech characteristic(s). An attempt is made at unravelling the different terminology used in relation to a well-known and validated approach to analysis, used in the United Kingdom and elsewhere. Complexities of current diagnostic labels and classifications in Speech Sound Disorder to describe cleft palate/VPI speech are discussed. What are the potential or actual clinical implications of this work? There needs to be a common language for describing and summarising cleft palate/VPI speech. Speech summary patterns based on narrow phonetic transcription and correct identification of aetiology are essential for the accurate classification of the speech disorder and identification of speech intervention approaches. There is an urgent need for research to identify the most appropriate type of contrastive (phonological) approach in cleft lip and/or palate.

Differences in craniofacial morphology between platybasic and nonplatybasic patients with velopharyngeal dysfunction and control subjects

INTRODUCTION

This study aimed to identify the characteristics of cranial-base morphology in platybasic and nonplatybasic patients with palatal anomalies and velopharyngeal dysfunction (VPD) compared with control subjects to investigate structural factors related to craniofacial morphology that affect the nasopharyngeal space and may influence velopharyngeal function, and to develop precise treatments for specific patients with VPD.

METHODS

Three hundred eighty-six patients with VPD and various palatal anomalies were studied retrospectively. The control group included 126 healthy patients with normal speech. Lateral cephalometric images assessed craniofacial morphology.

RESULTS

Nonplatybasic patients and control subjects had larger SNA, S-Ba-Ptm, and N-Ba-PP angles (in the craniomaxillary complex), and platybasic patients had larger nasopharyngeal ANS-Ptm-Ve and Ba-S-Ptm angles and longer Ve-T and Ve-Ba distances than the nonplatybasic patients. All study patients had larger ANB, Gn-Go-Ar, and PP-MP angles (in the craniomandibular complex). Nonplatybasic patients had smaller Ba-SN angles than platybasic patients and controls because of more acute N-S-Ptm angle. Among the nonplatybasic patients, Ve-T length tended to be shorter (with no significant difference between groups) and located more inferiorly (because of the smallest ANS-Ptm-Ve angle) in relation to the maxilla. Thus, the nasopharynx was narrower horizontally but longer vertically than in patients with platybasia.

CONCLUSIONS

Cranial-base flexure influences the shape of the skull base and facial-skeletal structure and may alter the pharyngeal space between them. This finding should help improve preoperative planning regarding the effect of the pharyngeal flap height relative to the nasopharynx and oropharynx ratio that affects surgical outcomes, such as resonance and residual VPD. In patients with Class III malocclusion and maxillary constriction, careful planning of presurgical orthodontic treatment is needed in maxillary advancement procedures. Orthodontic and surgical collaboration can help prevent postoperative VPD, especially in platybasic patients.

The Impact of Maxillary Osteotomy on Fricatives in Cleft Lip and Palate: A Perceptual Speech and Acoustic Study

INTRODUCTION

Abnormal facial growth is a recognized outcome in cleft lip and palate (CLP), resulting in a concave profile and a class III occlusal status. Maxillary osteotomy (MO) is undertaken to correct this facial deformity, and the surgery can impact speech articulation, although the evidence remains limited and ill-defined for the CLP population.

AIMS

The aim of the study was to investigate the impact of MO on the production of the fricatives /f/ and /s/, using perceptual and acoustic analyses, and to explore the nature of speech changes.

METHODS

Twenty participants with CLP were seen 0-3 months pre-operatively (T1) and 3 months (T2) and 12 months (T3) after MO. A normal group (N = 20) was similarly recruited. Perceptual speech data was collected according to a validated framework and ratings made on audio and audio-video recordings (VIDRat). Spectral moments were centre of gravity (CG), standard deviation (SD), skewness (SK) and kurtosis (KU). Reliability studies were carried out for all speech analyses.

RESULTS

For the CLP group, VIDRat identified dentalization/interdentalization as the main type of pre-operative error for /s/ with a statistically significant improvement over time, χ2(2) = 6.889, p = 0.032. Effect sizes were medium between T1 and T3 (d = 0.631) and small between T2 and T3 (d = 0.194). For the acoustic data, effect sizes were similarly medium between T1 and T2 (e.g., SK, /f/ d = 0.579, /s/ d = 0.642) and small between T1 and T3 across all acoustic parameters. Independent t tests showed mainly statistically significant differences between both groups at all time points with large effect sizes (e.g., T2 CG, t = -4.571, p < 0.001, d =1.581), indicating that /s/ was not normalized post-operatively. For /f/, differences tended to be at T1 with large effect sizes (e.g., CG, t = -2.307, p = 0.028, d = 0.797), reflecting normalization.

CONCLUSIONS AND IMPLICATIONS

This is the first speech acoustic study on /f/ for individuals with CLP undergoing MO. The surgery has a positive impact on /f/ and /s/, which appear to stabilize 3 months post-operatively. Speech changes are an automatic and a direct consequence of the physical changes brought about by MO, effecting articulatory re-organization. The results of the study have direct clinical implications for the clinical care pathway for patients with CLP undergoing MO.

Are Vowels Normalized After Maxillary Osteotomy? An Acoustic Study in Cleft Lip and Palate

BACKGROUND

Maxillary hypoplasia is a common skeletal condition in cleft lip and palate (CLP). Maxillary osteotomy is typically used to reposition the maxilla in CLP with maxillary hypoplasia. Previous studies have suggested that vowel articulations are adjusted postsurgically due to altered vocal tract configuration and articulatory reorganization. This acoustic study aims to investigate whether vowels are normalized postoperatively and to explore the nature of articulatory reorganization.

METHODS AND PROCEDURES

A prospective study was conducted to examine the vowel production of a group of individuals with CLP (N = 17) undergoing maxillary osteotomy and a group of normal controls (N = 20), using speech acoustic data. The data were collected at 0 to 3 months presurgery (T1), 3-months (T2), and 12-months (T3) postsurgery. General linear model repeated measures and independent t-tests were undertaken on F1, F2, and vowel space area.

RESULTS

General linear model repeated measures revealed no main effects of time for F1 (F [2, 22] = 1.094, P = 0.352), F2 (F [2, 22] = 1.269, P = 0.301), and vowel space area (F [2, 28] = 0.059, P = 0.943). Independent t-tests showed statistically significant differences (P < 0.05) for all acoustic parameters and all vowels between the CLP and the normal groups at all time points.

CONCLUSIONS

Vowels were not normalized after maxillary osteotomy despite positive anatomical changes within the oral cavity. Individuals with CLP tended to adjust their vowel articulatory gestures to match presurgical patterns. The nature of articulatory reorganization appears to be prompt, sensory-driven, complete, and permanent.

Videofluoroscopic Findings as Predictors of Velopharyngeal Insufficiency After Orthognathic Surgery in Patients With Cleft Lip and Palate

BACKGROUND

Midface retrusion is a common problem in patients with cleft lip and palate owing to the lack of adequate growth of the maxilla. Midface advancement surgery is a definite treatment for midface retrusion; however, the subsequent oropharyngeal airway changes might result in velopharyngeal insufficiency (VPI) in affected patients. Determining the predictors of VPI beforehand and modifying the surgical procedure would be beneficial.

MATERIALS AND METHODS

A retrospective review of 42 patients with cleft lip and palate who underwent orthognathic surgery from 2013 to 2014 was performed. A total of 25 patients met the inclusion criteria and had undergone complete pre- and postsurgery videofluoroscopy, nasopharyngoscopy (NPS), and speech assessment. We compared 2 groups of patients, those who showed NPS finding changes of more than 0.1 (8 patients) and those without changes (17 patients), by measuring the distances of the contact point to the tip of the velum, gap size at maximum closure (MC) and rest, contact area length, lateral wall closure rate, closure velocity, and 2 angles (from the velum to the hard palate and genu) at MC and rest. The amount of maxillary advancement was also recorded.

RESULTS

Among the 8 patients with NPS finding changes, 3 underwent Furlow palatoplasty for VPI. No significant difference was found in the amount of maxillary advancement between the groups (5.8 vs 5.7 mm). Significant differences were found in the preoperative gap size at MC and angle at the genu at MC (P = 0.035 and .012). These could be considered as the predictors before surgery. After surgery, a significant difference was found in the contact area, lateral wall closure rate, and gap size at MC (P = 0.005, 0.018, and 0.01).

CONCLUSION

Videofluoroscopy is a relatively applicable method of determining dynamic changes in the velum function. By performing videofluoroscopy before midface advancement surgery in patients with cleft lip and palate, we may predict the risk of VPI and consider alternative surgical strategies.

Velopharyngeal Space Assessment in Patients Undergoing Le Fort 1 Maxillary Advancement

Background:

The effects of maxillary advancement on velopharyngeal anatomy have primarily been studied using lateral cephalometric radiographs. However, with recent advances in orthognathic surgery, there is an increased need for more detailed and precise imaging such as computerized tomographic (CT) scan reconstructions, to help in surgical planning and to measure outcomes. The purpose of this study was to compare the pre- and post-operative velopharyngeal anatomic configuration modifications as measured on CT scans.

Methods:

This is a retrospective cohort study of 44 patients with and without cleft palate who were treated with maxillary advancement. The pre- and post-operative CT scans were compared with respect to pre-established landmarks. Linear distances, cross-sectional areas, and volumes were measured using 3-dimensional CT scan reconstructions.

Results:

For the linear distances measured, a statistically significant difference was found when comparing the pre- and post-operative measures of the narrowest part of the nasopharynx and the narrowest part of the retropalatal airway space (P = 0.001 and 0.026, respectively). Retropalatal cross-sectional areas, nasopharyngeal cross-sectional areas, and the volumetric assessment of the nasopharyngeal space showed no statistically significant differences when comparing pre- and post-operative scans (P < 0.05). Mean changes in the measures did not differ over time (pre- and post-operative) depending on whether there was a prior history of cleft palate repair.

Conclusions:

Although structural modifications of the pharyngeal space are inherent to maxillary advancement, its surface area and volume do not significantly change. The use of 3-dimensional reconstruction using CT scans should be the first choice for evaluation of the upper airway.

Effect of Maxillary Osteotomy on Speech in Cleft Lip and Palate: Instrumental Outcomes of Velopharyngeal Function

Objective:

To investigate the effect of maxillary osteotomy on velopharyngeal function in cleft lip and palate (CLP) using instrumental measures.

Design:

A prospective study.

Participants:

A consecutive series of 20 patients with CLP undergoing maxillary osteotomy by a single surgeon were seen at 0 to 3 months presurgery (T1), 3 months (T2), and 12 months (T3) post-surgery.

Interventions:

Nasalance was measured on the Nasometer II 6400. For videofluoroscopy and nasendoscopy data, visual perceptual ratings, for example, palatal lift angle (PLAn), and quantitative ratiometric measurements, for example, closure ratio (CRa), were made using a validated methodology and computer software. Reliability studies were undertaken for all instrumental measures.

Main Outcome Measures:

Repeated measures analysis of variance (with time at 3 levels) for nasalance and each velar parameter. Planned comparisons across pairs of time points (T1-T2, T1-T3, and T2-T3) including effect sizes.

Results:

A significant difference over time was found for nasalance ( P = .001) and planned comparisons across pairs of time points were significant between T1 and T2 ( P = .008), T1 and T3 ( P = .002), but not between T2 and T3 ( P = .459) providing evidence that maxillary osteotomy can impact on nasalance adversely and that the changes seen are permanent and stable. There were also significant differences over time for PLAn ( P = .012) and CRa ( P = −.059) and planned comparisons for both velar parameters reflected similar findings to those of nasalance.

Conclusions:

Maxillary osteotomy can adversely affect velopharyngeal function in patients with CLP. The study provides evidence for a much earlier post-surgery review even as early as 3 months after surgery.

Speech of Patients With Unilateral Complete Cleft Lip and Palate: Comparison of Three Different Surgical Protocols for Primary Repair

BACKGROUND AND AIMS

Between 1997 and 2014, 3 protocols have been used in out cleft unit for primary repair of unilateral cleft lip and palate. During the Scandcleft randomized controlled trial closing the soft palate and lip at 4 months and the hard palate at 12 months (Protocol 1) was compared with closing the entire palate at 12 months (Protocol 2). Protocol 3 comprises closure of the lip and hard palate with a vomer flap at 4 months and the soft palate at 10 months. The purpose of this study was to compare subsequent velopharyngeal competence at age of 3 and 5 years.

PATIENTS AND METHODS

The study consisted of 160 non-syndromatic patients with a unilateral cleft lip and palate. Protocol 3 was retrospectively compared with Protocols 1 and 2 within the previously published Scandcleft study.

RESULTS

At 3 years of age, normal or borderline competent velopharyngeal function was found in 68% of patients in Protocol 1, 74% of patients in Protocol 2, and 72% of patients in Protocol 3. At 5 years of age, the corresponding figures were 84%, 82%, and 92%. 21% of patients in Protocol 1, 4% in Protocol 2, and 23% in Protocol 3 had palatal reoperations before the age of 5 years.

CONCLUSION

No significant differences emerged in velopharyngeal competence at age 3 years between the 3 protocols. Palatal reoperations were performed earlier in patient groups 1 and 3, explaining the difference in the velopharyngeal competence rate at the 5-year time-point.

Le Fort I osteotomy in cleft patients: Maxillary advancement and velopharyngeal function

BACKGROUND

Maxillary advancement may affect speech in cleft patients.

AIMS

To evaluate whether the amount of maxillary advancement in Le Fort I osteotomy affects velopharyngeal function (VPF) in cleft patients.

METHODS

Ninety-three non-syndromic cleft patients (51 females, 42 males) were evaluated retrospectively. All patients had undergone a Le Fort I or bimaxillary (n = 24) osteotomy at Helsinki Cleft Palate and Craniofacial Center. Preoperative and postoperative lateral cephalometric radiographs were digitized to measure the amount of maxillary advancement. Pre- and postoperative speech was assessed perceptually and instrumentally by experienced speech therapists. Student's t-test and Mann-Whitney's U-test were used in the statistical analyses. Kappa statistics were calculated to assess reliability.

RESULTS

The mean advancement of A point was 4.0 mm horizontally (range: -2.8-11.3) and 3.9 mm vertically (range -14.2-3.9). Although there was a negative change in VPF, the amount of maxillary horizontal or vertical movement did not significantly influence the VPF. There was no difference between the patients with maxillary and bimaxillary osteotomy.

CONCLUSIONS

The amount of maxillary advancement does not affect the velopharyngeal function in cleft patients.

Predictors of Velopharyngeal Dysfunction in Individuals With Cleft Palate Following Surgical Maxillary Advancement: Clinical and Tomographic Assessments

Objective:

To investigate whether morphofunctional velopharyngeal aspects may be considered predictors of appearance or worsening of hypernasality in patients with cleft palate after surgical maxillary advancement (MA).

Design:

Prospective.

Setting:

National referral center for cleft lip and palate rehabilitation.

Participants:

Fifty-two patients with repaired cleft palate, skeletal class III malocclusion, and normal speech resonance completed speech audio recordings and cone-beam computed tomography examination before (T1) and, on average, 14 months after (T2) MA.

Interventions:

Hypernasality was rated by 3 experienced speech-language pathologists using a 4-point scale and morphofunctional aspects on a 3-point scale. Cone-beam computed tomography image measurements were performed using Amira and Dolphin 3D software. For each velopharyngeal morphofunctional aspect analyzed, patients were compared according to the absence (G1) and presence (G2) of postoperative hypernasality.

Main Outcome Measures:

Comparison of hypernasality scores between T1 and T2 and association between hypernasality and each velopharyngeal morphofunctional aspect.

Results:

Significant difference was observed between T1 and T2 for hypernasality ( P = .031) and between G1 and G2 ( P = .015) for velar mobility, with significant association between this variable and hypernasality on T2 ( P = .041).

Conclusions:

Levator veli palatini mobility influenced the appearance of hypernasality after MA.

Scandcleft Project, Trial 1: Comparison of Speech Outcome in Relation to Timing of Hard Palate Closure in 5-Year-Olds With UCLP

OBJECTIVE

To compare in-depth speech results in Scandcleft Trial 1 as well as reference data from peers without cleft palate (CP).

DESIGN

A prospective randomized clinical trial.

SETTING

A Danish and a Swedish CP center.

PARTICIPANTS

143 of 148 randomized 5-year-olds with unilateral cleft lip and palate. All received lip and velum closure at 4 months, and hard palate closure at 12 months (arm A) or 36 months (arm B).

MAIN OUTCOME MEASURES

A composite measure based on velopharyngeal competence (VPC) or velopharyngeal incompetence (VPI), an overall assessment of VPC from connected speech (VPC-Rate), Percentage of Consonants Correct (PCC-score), and consonant errors. Speech therapy visits, average hearing thresholds, and secondary pharyngeal surgeries documented burden of treatment.

RESULTS

Across the trial, 61.5% demonstrated VPC and 38.5% VPI. Twenty-two percent of participants achieved age appropriate PCC-scores. There were no statistically significant differences between arms or centers for these measures. In the Danish center, arm B: achieved lower PCC-scores (P = .01); obtained PCC-scores without s-errors below 79% (P = .002); produced ≥3 active oral cleft speech characteristics (P = .004) than arm A. In both centers, arm B attended more speech visits.

CONCLUSIONS

At age 5, differences between centers and treatment arms were not statistically significant for VPC/VPI, but consonant proficiency differed between treatment arms in the Danish center. Poor speech outcomes were seen for both treatment arms. Variations between centers were observed. As the Swedish center had few participants, intercenter comparisons should be interpreted with caution.

Validity of auditory perceptual assessment of velopharyngeal function and dysfunction - the VPC-Sum and the VPC-Rate

Overall weighted or composite variables for perceptual auditory estimation of velopharyngeal closure or competence have been used in several studies for evaluation of velopharyngeal function during speech. The aim of the present study was to investigate the validity of a composite score (VPC-Sum) and of auditory perceptual ratings of velopharyngeal competence (VPC-Rate). Available VPC-Sum scores and judgments of associated variables (hypernasality, audible nasal air leakage, weak pressure consonants, and non-oral articulation) from 391 5-year olds with repaired cleft palate (the Scandcleft project) were used to investigate content validity, and 339 of these were compared with an overall judgment of velopharyngeal competence (VPC-Rate) on the same patients by the same listeners. Significant positive correlations were found between the VPC-Sum and each of the associated variables (Cronbachs alpha 0.55-0.87, P < 0.001), and a moderately significant positive correlation between VPC-Sum and VPC-Rate (Rho 0.698, P < 0.01). The latter classified cases well when VPC-Sum was dichotomized with 67% predicted velopharyngeal competence and 90% velopharyngeal incompetence. The validity of the VPC-Sum was good and the VPC-Rate a good predictor, suggesting possible use of both measures depending on the objective.