The overt submucous cleft palate possesses the classic triad of bifid uvula, hard palate notching, and zona pellucida, as described by Calnan in 1954.1 The levator veli palatini muscle is variably clefted, with a less effective levator sling, and sometimes culminates in abnormal speech. In addition, the clefted muscle is misaligned anteriorly in a sagittal orientation. The most common symptom of submucous cleft palate is velopharyngeal dysfunction, which leads to hypernasal speech, grimacing, abnormal nasal emission, altered intraoral air pressures, altered speech sound development, and secondary phonatory symptoms and is believed to occur in 5 percent to 10 percent of cases.2,3 Occult submucous cleft palate, described by Kaplan in 1975, lacks features of Calnan’s triad, but the levator veli palatini muscle is similarly clefted and misaligned.4,5 True incidence of submucous cleft palate is unknown; early work by Weatherly-White et al.6 estimated the incidence of overt cases as approximately 0.08 percent in their study of more than 10,000 school children. The incidence of occult submucous cleft palate is unknown. Because patients will not be diagnosed until they are investigated for velopharyngeal dysfunction, the incidence is likely to be much higher than that encountered at cleft centers.7 Occult submucous cleft palate is harder to diagnose due to its lack of anatomical features. A number of imaging techniques are available, including magnetic resonance imaging and nasoendoscopy, but they are cumbersome and expensive.4,7 The study center has considerable experience in the diagnosis and management of occult submucous cleft palate. Over time, the authors found that the misaligned levator veli palatini results in an inverted, V-shaped, velar vaulting upon gag. This clinical sign can be identified during the initial examination and anatomically correlated at the time of surgery8 (Fig. 1).
The decision to surgically treat submucous cleft palate depends on thorough assessment by a speech pathologist to assess hypernasality and expose deviant compensatory articulation patterns, as well as intraoral examination with or without the use of videofluoroscopy or nasopharyngoscopy.3,9 The Furlow double-opposing Z-plasty has numerous advantages, as it (1) lengthens the palate while simultaneously anatomically repositioning the aberrantly oriented levator veli palatini muscles; (2) prevents the longitudinal scarring and velar shortening found with straight-line repairs; and (3) produces a built-in pharyngoplasty by narrowing the velopharyngeal port.2,10 The authors utilize this technique to repair both overt and occult submucous cleft palate.11
A large-sample study of Furlow palatoplasty repair of occult submucous cleft palate does not exist. The objectives of this study were to (1) evaluate the complication rate; (2) describe differences in outcome between overt and occult submucous cleft palate patients; and (3) identify features associated with surgical failure, such as age, syndromic status, and preoperative veli palatini function, as measured by the Pittsburgh Weighted Speech Score.
PATIENTS AND METHODS
Patients undergoing Furlow palatoplasty repair of symptomatic submucous cleft palate at the study center who had complete electronic medical records were collated. Data pertaining to demographics, surgery, complications, and preoperative and postoperative Pittsburgh Weighted Speech Score were stored in a secure electronic database. The Pittsburgh Weighted Speech Score, first reported in 1979, is a subjective assessment performed by speech pathologists trained in its use. Syndromic patients were identified, and need for secondary speech surgery, age at palatoplasty, and preoperative and postoperative speech scores were compared with those of the nonsyndromic cohort. Speech assessment was performed by speech pathologists experienced in the use of the Pittsburgh Weighted Speech Score. The attending surgeon performed an intraoral examination before and after surgery. Of particular interest was the morphology of velar elevation, specifically, the inverted, V-shaped, vaulted elevation pattern resulting from levator veli palatini malposition found in a submucous cleft palate.8
Submucous cleft palate exists on a spectrum, ranging from overt to occult. For the purposes of comparison in this study, classification was based on the presence or absence of features originally described by Calnan.1 Patients were classified as having an overt submucous cleft palate if they had a bifid uvula and zona pellucida. The study center has found hard palate notching to be a subjective examination finding, and different providers were not consistent in its identification. Consequently, its documentation is inconsistent; some providers choose not to look for it, whereas others decline to record it. It was excluded, therefore, from analysis. Patients were classified as having an occult submucous cleft palate if they lacked a zona pellucida and bifid uvula but demonstrated evidence of levator veli palatini muscle sagittal malposition on examination, with or without imaging.
Patients were examined for active levator veli palatini muscle function as evidenced by active velar elevation upon vocalization and with gag. Examination also looked for the V-shaped velar vaulting pattern described previously8 (Fig. 1). Videofluoroscopy was used to assess for active palatal elevation and lateral pharyngeal wall motion when there was diagnostic doubt after multidisciplinary assessment. Nasopharyngoscopy is not favored at the study center due to its invasive nature and its unreliability as a diagnostic tool, although this is not a universally held view.12,13
All surgical procedures were performed by one of nine attending surgeons, with or without resident assistance, with the patient under general anesthesia. Surgeons with fewer than four documented cases were excluded from comparative analysis due to statistical saturation. This resulted in the loss of six of 351 patients (1.7 percent) from this section of analysis.
Operative success in treating velopharyngeal dysfunction secondary to submucous cleft palate is defined as nonstigmatized speech, as evidenced by a Pittsburgh Weighted Speech Score of less than 7 with no recommendation for secondary speech surgery. A score of 5 or greater corresponds to detectable velopharyngeal insufficiency, as reported earlier by this center.9 However, a child would need very turbulent speech distortion and audible nasal emission to be eligible for speech surgery with a score of 5. At the study center, children would require a score of 7 before surgery would be advocated. A few patients in this study did have scores below 7, but they represent the extremely low end of the scale where surgery would be offered.
Data were analyzed using SPSS software (IBM Predictive Software, Armonk, N.Y.). Chi-square analysis was used in most comparisons. Need for secondary speech surgery was further analyzed using logistic regression with Cox and Snell analysis of variance. Variables were further assessed for significance using the Wald test. Except for the need for secondary speech surgery, which was addressed separately, the complication rate was zero in both groups, indicating that the model for expected values in chi-square analysis included cells that are less than 5; therefore, Fisher’s exact test was utilized. Comparisons of mean lateral wall motions utilized the Mann-Whitney U test.
Demographics and Complications
Between January of 2004 and January of 2018, the electronic records of 393 patients who underwent Furlow palatoplasty for symptomatic submucous cleft palate were reviewed. The preoperative or postoperative Pittsburgh Weighted Speech Score was unavailable for 42 patients, who were excluded. Of the remaining 351 patients, the male-to-female ratio was 1.36, and there were 331 white patients (94.3 percent), nine African American patients, three Asian American patients, and eight of unknown ethnicity. Patients with occult submucous cleft palate were more common (226 patients, 64.4 percent) than patients with the overt type (125 patients, 35.6 percent) (Tables 1 and 2).
Table 1. -
Summary of Key Demographics
||No. of Patients
| 0 to <2 years
| 2 to <5 years
| 5 to <10 years
| 10 to <15 years
| ≥15 years
| 15q13.3 duplication
| Other (1 case each)
VCFS, velocardiofacial syndrome; NF1, neurofibromatosis 1; SMCP, submucous cleft palate.
Table 2. -
Salient Comparisons Described in the Study
||Age at Surgery (yr)
||Need for SSS (%)
|Need for SSS
||6.9 (p > 0.05)
||16.9 (p < 0.05)
||15.1 (p < 0.05)
|No need for SSS
||7.3 (p = 0.42)
||15.6 (p = 0.04)
||7.4 (p < 0.001)
||24.4 (p < 0.001)
||7.5 (p = 0.001)
||14.1 (p = 0.035)
||5.1 (p = 0.81)
||20 (p = 0.297)
PWSS, Pittsburgh Weighted Speech Score; SSS, secondary speech surgery.
Mean age at palatoplasty was 7.2 years and mean follow-up was 2.2 years (range, 0 to 13.6 years). The study took into account all patients who underwent Furlow palatoplasty since the start of electronic medical records use at the study center. A few of the patients are still being followed, and the range reflects this. The mean preoperative Pittsburgh Weighted Speech Score was 14.6, compared with the mean postoperative score of 5.2 (p < 0.001).
Sixty patients required secondary speech surgery (discussed below). There were no other perioperative complications, including postoperative fistulas.
Syndromic versus Nonsyndromic
There were 90 syndromic patients. Velocardiofacial syndrome was the most common syndrome (41.1 percent), followed by Down syndrome (8.9 percent) (Tables 1 and 2). Syndromic patients were more likely to require secondary speech surgery than nonsyndromic patients (24.4 percent versus 9.2 percent, p < 0.001). Syndromic patients had a higher preoperative Pittsburgh Weighted Speech Score than nonsyndromic patients (15.6 versus 14.1, p = 0.04) and a higher postoperative speech score (7.5 versus 4.3, p < 0.001). There was no difference in the age at palatoplasty (7.3 years versus 7.1 years, p = 0.416). Thirty-six of 90 syndromic patients (40 percent) had overt submucous cleft palate versus 56 (60 percent) who had occult. Eighty-nine of 261 nonsyndromic patients (34.1 percent) had overt submucous cleft palate versus 172 nonsyndromic patients (65.9 percent), with no significant difference found. These proportions did not differ significantly from the overall cohort (all compared, p = 0.602).
Overt versus Occult
Patients with overt submucous cleft palate had a higher mean preoperative Pittsburgh Weighted Speech Score (15.7) than patients with occult type (14.1) (p = 0.035). The postoperative scores were significantly lower than preoperative scores for both groups (p < 0.001), but there was no significant difference between overt and occult submucous cleft palate (5.5 compared to 5.1) (p = 0.805). Change in mean speech score as a result of palatoplasty was 10.2 for overt submucous cleft palate versus 8.9 for patients with occult submucous cleft palate; the difference was nonsignificant (p = 0.175). Overt submucous cleft palate patients underwent palatoplasty at a younger age (6.5 years) than the occult group (7.5 years, p = 0.001). The mean follow-up of 2.2 years was similar for overt and occult submucous cleft palate (2.4 years compared to 2 years) (p = 0.172).
Secondary Speech Surgery
Sixty patients (17.1 percent) were recommended for secondary speech surgery. Forty-six of them underwent secondary surgery as recommended, one was given a palatal prosthesis, and 13 did not return for further follow-up. Of those who underwent the second surgery, 42 (91.3 percent) underwent pharyngoplasties (40 posterior pharyngeal flaps and two sphincter pharyngoplasties). The remainder underwent repeated Furlow palatoplasty (three patients) or a combination of palatoplasty and pharyngoplasty. There was no significant difference in requirement for secondary speech surgery rates between the overt and occult submucous cleft palate groups (25 patients/20 percent versus 34 patients/15.0 percent, respectively) (p = 0.313). Mean age at time of palatoplasty was not significantly different for those patients who required secondary surgery (6.9 years) versus those who did not (7.2 years) (p = 0.366). Mean preoperative and postoperative Pittsburgh Weighted Speech scores were higher (16.9 and 15.1, respectively) for patients who required secondary surgery compared with those who did not (14.2 and 3.4, respectively). Logarithmic regression showed a significant prediction for secondary speech surgery with increased preoperative score (p = 0.01). The same is true of postoperative score (p = 0.001). Of the six surgeons included in this study, secondary speech surgery rates varied from 0 to 22.77 percent (Table 3). No correlation was observed with time in practice or case volume.
Table 3. -
Absolute Numbers of Patients Requiring Secondary Speech Surgery by Surgeon
||Total No. of Cases
||No. of Cases Requiring SSS
||% of Cases Requiring SSS
SSS, secondary speech surgery.
Prepalatoplasty videofluoroscopy assessment was performed in 92 patients. Mean lateral wall motion was 65.4 percent. Active palatal motion without any limitation on lateral view was documented in 60 patients (65.2 percent). Patients who required secondary speech surgery had a prepalatoplasty lower mean lateral wall motion (58.6 percent) than those patients who did not need second surgery (68.2 percent), but the difference was not significant (p = 0.126). Documented impairment of active palatal motion was not correlated with secondary speech surgery (p = 0.522 by Fisher’s exact test).
V-shaped velar vaulting on gag elicitation during prepalatoplasty assessment was present in 208 patients (92 percent) with occult submucous cleft palate and 82 patients (65.6 percent) with overt submucous cleft palate.
This study took place at a single tertiary referral center where Furlow palatoplasty is the first-line technique for repair of submucous cleft palate. This surgical approach was effective in 82.9 percent of patients (80 percent with overt and 85 percent with occult submucous cleft palate) who met the center’s criteria for the correction of stigmatized speech (Pittsburgh Weighted Speech Score <7) with no recommendation for secondary speech surgery. Success rates were similar for both overt and occult submucous cleft palate, with no significant difference in the postoperative Pittsburgh Weighted Speech Score or the likelihood of having a recommendation for secondary speech surgery. The decision to recommend a second surgery is made on a case-by-case basis and is multifactorial but comprises three stages. In the first assessment, a patient must have a Pittsburgh Weighted Speech Score greater than 7 and continued stigmatized speech. In the second stage, these patients are discussed with the team, where possible confounding reasons for continued poor speech, including compensatory articulation patterns, neurological sequelae of any syndromic or systematic disease process, or social factors, are delineated. Finally, the patient and family are assessed to establish the social impact of continued speech pathology and the willingness to undergo secondary speech surgery. Stage 2 and this final stage may happen simultaneously. Higher preoperative Pittsburgh Weighted Speech Score and syndromic status were associated with a higher recommendation for secondary speech surgery. After an average follow-up of more than 2 years, Furlow palatoplasty was successful for more than 85 percent of patients. Except for the need for secondary speech surgery, there were no other complications and no fistulae documented in the medical records (0 percent). This is consistent with previous reports from the study center, which found a fistula rate of less than 1 percent.16
The Pittsburgh Weighted Speech Score dates back to 1979 and has been reported multiple times in the literature for the quantification of velopharyngeal dysfunction.9,14–16 As with all clinical assessments of velopharyngeal insufficiency, it is intrinsically subjective; however, it is utilized only by speech pathologists trained in its utilization. Furlow palatoplasty significantly reduced the mean Pittsburgh Weighted Speech Score, with patients achieving a mean postoperative score of 5.2, but this does indicate continuing borderline incompetent velopharyngeal insufficiency (score of 3 to 6) (Tables 1 through 3).9 This echoes the findings of previous studies that have also demonstrated high efficacy of the Furlow palatoplasty in the improvement of velopharyngeal insufficiency in submucous cleft palate, despite the inability to obtain normal perceptive resonance.3,17–20 One study of Furlow palatoplasty in the management of submucous cleft palate did utilize the Pittsburgh Weighted Speech Score as an assessment method. Swanson and colleagues18 reported mean postoperative scores of 1.7 for those patients undergoing palatoplasty under age 3 years, 2.3 for those aged 3 to 4 years, and 5.1 for those older than 5 years; however, it should be noted that their sample of patients had considerably lower preoperative scores (8.0 versus 14.6 in this study).
Mean age at time of palatoplasty was 7.2 years, which is not dissimilar to the mean age in the series reported by Mardini et al. (7.9 years) but older than that in the series presented by Ettinger et al., where the “late” cohort had a mean age of 6.4 years and the “early” cohort had a mean age of 2.4 years.21,22 Mean age in this study was significantly older in cases of occult submucous cleft palate (7.5 years) than in overt submucous cleft palate cases (6.5 years). Lack of visible features of a submucous cleft palate may delay diagnosis in occult cases.7 Other comparisons were nonsignificant, suggesting submucous cleft palate is a continuum rather than there being a clear distinction between overt and occult.
Age at intervention is based on timing of presentation, which is dependent on a range of factors (e.g., parental, geographic, school, primary/secondary care providers) outside the scope of this study. Optimal timing of submucous cleft palate repair is debated. Early literature advocated repair at any time from 16 to 18 months of age to 7 years, due to the risk of undesirable speech habits, which may persist postoperatively.20 In the study by Baek and colleagues,20 repair by Furlow palatoplasty after age 5.5 years was correlated with significantly poorer outcome (based on a universal assessment of hypernasality described by Henningsson et al.23); however, Baek et al. acknowledge that this was affected by the small sample size of patients over this age.20,23 Swanson et al.18 reported significantly higher postoperative Pittsburgh Weighted Speech scores in patients undergoing palatal repair over the age of 4 years. They noted several confounding factors in this finding; early referrals may reflect higher socioeconomic status and access to better speech therapy and educational opportunities.18 This study did not control for these factors either. Ettinger et al.21 and Mardini et al.22 found that timing of Furlow repair had no impact on speech quality.
In this study, 17.1 percent required secondary speech surgery after inadequate improvement in velopharyngeal insufficiency from Furlow palatoplasty. Patients who required secondary speech surgery had a significantly higher preoperative Pittsburgh Weighted Speech Score, but age at palatoplasty did not differ significantly from those not needing a second surgery. The secondary speech surgery rate was higher than that reported by some authors; Baek and colleagues20 reported no secondary speech surgery in their analysis of 74 patients, reporting that 87 percent of patients had achieved velopharyngeal competency. However, they utilized a different grading system than that used in this study (Pittsburgh Weighted Speech Score), making comparison difficult.20 Chen and colleagues17 assessed the 30 patients in their study using a perceptual assessment comprising nasal emission, nasal resonance, phonation, articulation and intelligibility, and/or videofluoroscopy. Classification of velopharyngeal insufficiency was a composite rating of the above (competent, marginal, incompetent), with 29 of the 30 patients graded as competent, but again, comparisons with this study are difficult to draw.17 Swanson and colleagues,18 who utilized the Pittsburgh Weighted Speech Score, reported a reoperation rate of 17.5 percent, with patients requiring secondary speech surgery trending toward a greater age at initial Furlow palatoplasty (p = 0.065). Syndromic patients’ significantly higher (24.4 percent versus 9.2 percent, p < 0.001) need for secondary speech surgery and neurological factors in some syndromic cases, such as Down syndrome and velocardiofacial syndrome, could be confounding. However, the decision-making process with the team, patient, and family involves distinguishing the pathology related to the cleft itself from other medical and social factors amenable to nonsurgical intervention.
Prepalatoplasty videofluoroscopy results were documented for 31.1 percent of patients included in this study. Use of objective tests varied by surgeon, with some choosing to use only clinical examination findings, particularly in more obvious cases of submucous cleft palate. In addition, patients varied in their ability to tolerate such tests. Over time, the use of objective tests, such as videofluoroscopy, decreased as the experience of the cleft team at the study center increased. Lateral wall motion varied greatly among patients, from 20 percent to 100 percent. Lateral wall motion tended to be lower for patients requiring secondary speech surgery, although not significantly. Previous literature has suggested that Furlow repair is most appropriate in patients with good lateral wall motion and short palates, which is not surprising given that the primary mechanism of the Furlow palatoplasty is to reduce the anterior-posterior velopharyngeal gap.2,4,24 However, other authors report no correlation between lateral wall motion and hypernasality after Furlow palatoplasty.25 Chen et al.17 preselected patients in their series based on small closure gaps on videofluoroscopy. Gosain et al.4 argued that these patients could have gained good speech outcomes had a pharyngoplasty been performed instead. Nearly all patients in this study undergoing secondary speech surgery had pharyngoplasty alone or in combination with repeated palatoplasty. Some advocate sphincter palatoplasty in cases of very poor lateral wall motion, as it brings tissue toward the center of the defect.2
Definitive diagnosis of occult submucous cleft palate requires dissection of the soft palate, with visualization of aberrantly oriented muscle fibers precluding accurate estimation of the incidence.4,7 It is possible that palatoplasty could be undertaken in the absence of palatal pathology, but in no cases did this occur. All palates demonstrated anomalies in the levator veli palatini muscle, ranging from frank clefting in overt variants to misaligned muscle fibers in occult types. The presence of inverted, V-shaped, velar vaulting upon gag has previously been discussed by the senior author (J.E.L.), who believes it to be a reliable diagnostic sign; however, it remains unvalidated.8 It was present on preoperative assessment in both occult and overt submucous cleft palate cases; however, it is routinely utilized only for assessing occult submucous cleft palate. Since overt clefts are more obvious, it was not performed or documented in many overt cases. In occult cases, it was documented in 92 percent of cases. It is possible it was present in the remainder of occult submucous cleft palate patients but not looked for or documented.
This is the largest study of patients undergoing Furlow palatoplasty for the repair of submucous cleft palate. Other studies comprise fewer than 80 surgical cases.3,17–20,26 The study was designed to report the experience of a high-volume tertiary center, not to advocate changes in practice.
Limitations include the fact that the study is retrospective and unable to define relative risk. It is reliant on previous documentation, so omissions in documentation will feed through into the study, as alluded to in the discussion of velar vaulting. It reviews outcomes of those patients who underwent Furlow palatoplasty and does not discuss the many patients with submucous cleft palate who are managed conservatively. Quantitation of velopharyngeal insufficiency was by the Pittsburgh Weighted Speech Score, which limits the study’s applicability to centers that do not utilize this measure. The possibility that mucosal flap necrosis occurred and healed before postoperative visits cannot be excluded. The 2.2-year mean follow-up with a large range may cause later complications and deteriorating speech quality to be missed.
Successful repair of submucous cleft palate with Furlow palatoplasty, defined as a resolution of stigmatizing speech, a Pittsburgh Weighted Speech Score of less than 7, and no recommendation for secondary speech surgery, was 82.9 percent at a mean follow-up of 2.2 years. Besides secondary speech surgery, there were no documented postoperative complications. Outcomes did not differ for occult or overt subtypes, even though the former presented later in life, on average, and with less severe velopharyngeal insufficiency. Syndromic status and higher preoperative speech scores were associated with the need for secondary speech surgery, but submucous cleft palate subtype and age at time of Furlow palatoplasty were not. An inverted, V-shaped, velar vaulting on gag was documented in 92 percent of patients with occult submucous cleft palate.
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