Prevalence,Cause,and Location of Palatal Fistula in Operated Complete Unilateral Cleft Lip and Palate: Retrospective Study

Abstract

Objective

To evaluate the prevalence of fistulas after palate repair and analyze their location and association with possible causal factors.

Design

Retrospective analysis of patient records and evaluation of preoperative initial photographs.

Setting

Tertiary craniofacial center.

Participants

Five hundred eighty-nine individuals with complete unilateral cleft lip and palate that underwent palate repair at the age of 12 to 36 months by the von Langenbeck technique, in a single stage, by the plastic surgery team of the hospital, from January 2003 to July 2007.

Interventions

The cleft width was visually classified by a single examiner as narrow, regular, or wide. The following regions of the palate were considered for the location: anterior, medium, transition (between hard and soft palate), and soft palate.

Main outcome measures

Descriptive statistics and analysis of association between the occurrence of fistula and the different parameters were evaluated.

Results

Palatal fistulas were observed in 27% of the sample, with a greater proportion at the anterior region (37.11%). The chi-square statistical test revealed statistically significant association (P ≤ .05) between the fistulas and initial cleft width (P = .0003), intraoperative problems (P = .0037), and postoperative problems (P = .00002).

Conclusions

The prevalence of palatal fistula was similar to mean values reported in the literature. Analysis of causal factors showed a positive association between palatal fistulas with wide and regular initial cleft width and intraoperative and postoperative problems. The anterior region presented the greatest occurrence of fistulas.

Keywords

cleft lip cleft palate surgery plastic

The primary palatoplasty aims to reconstruct the anatomical structures that separate the nasal and oral cavities. When performed in proper time, it can achieve good outcomes in speech development, nasal resonance, and velopharyngeal competence (Bertier et al., 2007; Diah et al., 2007; Phua and Chalain, 2008; Losken et al., 2011) as well as hearing, dental arch shape, and facial growth (Chait et al., 2002; Parwaz et al., 2009; Landheer et al., 2010).

The von Langenbeck technique is the palatoplasty technique most known and used (Bertier et al., 2007; Agrawal, 2009), accounting for 60% of all palatoplasties performed around the world (Billmire, 2008). It is performed by the approximation of mucoperiosteal flaps with the aid of wide lateral releasing incisions. Closure is performed in three layers, namely nasal floor, muscle tissue, and oral mucosa.

One of the complications of palatoplasty is the occurrence of fistula, a failure of the primary repair to heal (Lohmander-Agerskov et al., 1997), with different dimensions and shapes. It may compromise speech (hypernasality and articulation problems) as well as cause discomfort to the patient because of outflow of liquids through the nose (Amaratunga, 1988; Muzaffar et al., 2001; Wilhelmi et al., 2001; Smith et al., 2007).

Several factors may influence the occurrence of fistulas, including the type of surgical technique employed for palate closure (Amaratunga, 1988; Carstens et al., 2011; Landheer et al., 2010; Losken et al., 2011), initial cleft width (Parwaz et al., 2009; Landheer et al., 2010; Losken et al., 2011), early or advanced age at surgery (Emory et al., 1997; Andersson et al., 2008), and plastic surgeon's experience (Emory et al., 1997; Andersson et al., 2008; Phua and Chalain, 2008). Fistulas may occur anywhere along the palate and are more frequent in the hard palate and the transition between hard and soft palate (Oneal, 1971; Amaratunga, 1988; Cohen et al., 1991).

The prevalence of fistula after primary palatoplasty reported in the literature ranges from 2% to 45% (Berkman, 1978; Åbyholm et al., 1979; Amaratunga, 1988; Cohen et al., 1991; Emory et al., 1997; Gunther et al., 1998; Wilhelmi et al., 2001; Yu et al., 2001; Bresnick et al., 2003; LaRossa et al., 2004; Inman et al., 2005; Bekerecioglu et al., 2005; Helling et al., 2006; Diah et al., 2007; Smith et al., 2007; Phua and Chalain, 2008; Agrawal, 2009; Parwaz et al., 2009; Landheer et al., 2010; Carstens, 2011; Losken et al., 2011).

Some researchers consider the palatal fistula only when it is located in the secondary palate (Emory et al., 1997; Parwaz et al., 2009; Landheer et al., 2010), called true fistulas (Phua and Calain; 2008), including fistulas of the anterior palate, hard palate, transition between hard and soft palate, and soft palate (Amaratunga, 1988; Emory et al., 1997; Diah et al., 2007; Andersson et al., 2008; Parwaz et al., 2009; Landheer et al., 2010). However, others also include fistulas in the primary palate (Åbyholm et al., 1979; Cohen et al., 1991; Phua and Chalain, 2008; Murthy, 2011), classified as pre-alveolar, post-alveolar, or anterior fistula (Phua and Chalain, 2008; Murthy, 2011).

This marked variation of data on palatal fistulas differs between authors, either in the definition or classification, often without a clear distinction between fistulas caused by a failure of surgery and those intentionally maintained. Suggestions of classifications were reported, yet without consensus in the literature (Cohen et al., 1991; Muzaffar et al., 2001).

The presence of palatal fistulas compromises the treatment quality and is a great challenge in the rehabilitation of individuals with cleft lip and palate.

Therefore, the professional team at the Hospital for Rehabilitation of Craniofacial Anomalies (HRAC-USP), committed with the rehabilitation of these individuals, aimed to expand the knowledge on palatal fistulas by evaluation of their prevalence in addition to analyzing the association with possible causal factors.

Material and Methods

Prior to its start, this study was approved by the Institutional Review Board of HRAC-USP (protocol n. 211/2011).

This retrospective study evaluated the consecutive records of 921 patients with complete unilateral cleft lip and palate, without syndromes or associated malformations, of both sexes, regardless of ethnicity. Patients underwent primary palatoplasty in the period from January 2003 to July 2007, and the study sample included 589 patients meeting the following inclusion criteria: palate repair at the age of 12 to 36 months in a single stage using the von Langenbeck technique by the plastic surgery team of the institution, which was composed of 11 plastic surgeons during the study period.

The occurrence of fistula and intraoperative and postoperative problems was assessed from the patient records. The initial cleft width was evaluated by analysis of preoperative intraoral photographs from the files and visually classified as narrow, regular, or wide as suggested by Ozawa (2001). The cleft was considered narrow if it was smaller than 1/5 of the total width of the palate; regular, if the cleft width was greater than 1/5 and smaller than 3/5 of the total width of the palate; and wide, if the cleft width was larger than 3/5 of the total width of the palate. Because this is a subjective evaluation, in order to assure the correct and reliable classification of the initial cleft width, three photographic images predefined as narrow, regular, and wide, were selected to serve as parameter for the classification (Figs. 1, 2, and 3, respectively).

Figure 1

Narrow cleft lip and palate.

Figure 2

Medium cleft lip and palate.

Figure 3

Wide cleft lip and palate.

The initial cleft width was assessed by a single examiner, a specialist in pediatric dentistry. To determine the reliability of data collected on the initial cleft width, the intra-examiner agreement was evaluated by the kappa test, which revealed a value of .92. The results of prevalence of fistula and association with causal factors were analyzed by descriptive statistics and the chi-square test, at a significance level of 5%.

Results

Data were obtained from 589 patients, including 376 (63.84%) boys and 213 (36.16%) girls, with cleft on the right side in 199 (33.79%) cases and on the left side in 390 (66.21%). Simonart's band was observed in 137 (23.26%) individuals. Data on initial cleft width are presented in Figure 4.

Figure 4

Proportions and numerical distributions of initial cleft width.

The mean age on accomplishment of palatoplasty was 17.3 months. The prevalence of fistulas in this sample was 27% (n= 159), and their location according to information available on the patient records is presented in Table 1.

Table 1

Numeric and Percentage Distributions of Location of Fistulas Observed per Individual in the Study

Location	n	%
Anterior palate	59	37.11
Medium region of the palate	51	32.08
Transition between hard and soft palate	32	20.12
Soft palate	8	5.03
Medium region of the palate/transition region	1	0.63
Medium region of the palate/soft palate	1	0.63
Not mentioned	7	4.40
Total	159	100

Intraoperative problems were reported in 236 (40.06%) cases, depicted in Table 2. Postoperative problems were observed in 218 (37%) cases, with 161 (73.85%) being mediate (occurring 2 hours or more after completion of surgery) and 57 (26.15%) being immediate (occurring in the period up to 2 hours after surgery) (Table 3).

Table 2

Numeric and Percentage Distributions of Intraoperative Difficulties Reported in the Sample

Types of difficulties	n (%)
Excessive tissue handling	9(1.53)
Tearing	29 (4.92)
Fibrous tissue	01 (0.17)
Suture under tension	41 (6.96)
Large tissue displacement	163 (27.67)
Formation of dead spaces	97 (16.47)
Excessive bleeding	34 (5.77)
Transudation	50 (8.49)

Table 3

Numeric Distribution of the Types of Postoperative Problems Reported in the Sample, Grouped in Immediate and Mediate

Types of problems	Immediate (up to 2 hours after surgery), n (%)	Mediate (2 hours or more after completion of surgery), n (%)
Tooth at the fistula region	—	21 (7.31)
Hemorrhage	22 (7.66)	17 (5.93)
Vomiting	28 (9.76)	87 (30.32)
Fever	10 (3.48)	62 (21.60)
Airway pathologies	09 (3.13)	19 (6.62)
Necrosis	—	03 (1.05)
Intensive Care Unit	08 (2.79)	01 (0.35)

The chi-square test was applied to analyze the association between presence of fistulas and the following variables: sex, cleft side, presence of Simonart's band, initial cleft width, age of child on primary palatoplasty, intraoperative problems, surgeon performing the palatoplasty, and postoperative problems. The results are presented in Table 4.

Table 4

Association Test Between the Occurrence of Fistula and the Variables Studied

Variables	P
Sex	.209
Cleft side	.187
Simonart's band	.512
Cleft width	.0003^*
Age at palatoplasty	.148
Surgeon	.019^*
Transoperative problems	.0037^*
Postoperative problems	.00002^*

Significant values (P ≤ .05).

There was a statistically significant association between the presence of fistula and the initial cleft width. This association was confirmed when data were crossed between wide X narrow clefts (P= .00002) and regular X narrow (P= .0012).

After observation of the statistically significant association between intraoperative problems and fistulas, each of the problems was analyzed individually, showing that excessive tissue handling, presence of fibrous tissue, excessive bleeding, and presence of transudations during surgery did not present association, with values of P = .234, P = .099, P = .468, and P = .867, respectively. The occurrence of tears (P = .02), large tissue displacement (P = .02) in the surgical technique, as well as suture under tension (P = .01) and formation of dead spaces (P = .003) demonstrated statistically significant associations with fistula occurrence, with values of P < .05 (Table 5).

Table 5

Association Test Between the Occurrence of Fistula and Each Intraoperative Problem Analyzed

Intraoperative problems	P
Excessive tissue handling	.234
Mucosal tearing	.02^*
Fibrous tissue	.099
Suture under tension	.01^*
Wide tissue displacement	.02^*
Dead spaces	.003^*
Hemorrhage	.468
Transudations	.867

Significant values (P ≤ .05).

The statistically significant association between the prevalence of fistulas and postoperative problems (P = .00002) showed a predominance of mediate problems (P = .000002), occurring 2 hours or more after completion of the surgical procedure.

Considering each of the postoperative problems individually associated with the presence of the cleft, it was observed that hemorrhage (P = .015), fever (P = .0003), airway pathologies (P = .0002), and tissue necrosis (P = .004) had statistically significant associations with the occurrence of fistula. This was not observed for the occurrence of vomiting (P = .99) (Table 6).

Table 6

Association Test Between the Occurrence of Fistula and Each Postoperative Problem Analyzed

Postoperative problems	P
Hemorrhage	.015^*
Vomiting	.99
Fever	.0003^*
Airway pathology	.0002^*
Necrosis	.004^*

Significant values (P ≤ .05).

Discussion

This study was conducted on a large-sized sample with a single type of cleft and submitted to palate repair by the same surgical technique, thus standardizing the sample to reduce the number of interfering factors as much as possible.

A ratio of 2:1 for affected males versus females and for clefts on the left versus right side a ratio of 2:1 for affected males versus females and for clefts on the left versus right side observed in this study agrees with data in the literature for complete unilateral cleft lip and palate (Silva Filho et al., 2000; Freitas et al., 2004; Silva Filho and Freitas, 2007).

Even though no studies have considered the cleft side as a variable in the occurrence of fistulas, this information was analyzed and revealed no positive association in the prevalence of fistula in right or left unilateral clefts (P = .18). No positive association was also observed in relation to sex, similar to the reports of Cohen et al. (1991), Emory et al. (1997), Muzaffar et al. (2001), Andersson et al. (2008), Phua and Chalain (2008), Parwaz et al. (2009), and Landheer et al. (2010). However, they disagree with the findings of Amaratunga (1998), who observed greater occurrence of fistula in males due to unknown reasons.

The presence of Simonart's band in 22% of the sample was similar to data in the literature (Semb and Shaw, 1991; Silva Filho et al., 1994), yet its presence was not associated with the prevalence of fistula (P = .512). The presence of this structure may be associated to the cleft width, making it narrower, possibly interfering with the final outcomes of surgical treatment. For this reason, some researchers suggest exclusion or separate analysis of individuals with Simonart's band (Nollet et al., 2005; Williams et al., 2011).

The initial cleft width in this study demonstrated association with the presence of fistula and wide and regular clefts compared to the narrow (P = .00002 and P = .0012, respectively). Though evaluated in different manners, the initial cleft width was also positively associated with the prevalence of palatal fistulas by some authors (Musgrave and Bremner, 1960; Amaratunga et al., 1988; Cohen et al., 1991; Muzaffar et al., 2001; Helling et al., 2006; Andersson et al., 2008), though others (Åbyholm et al., 1979; Emory et al., 1997; Wilhelmi et al., 2001) did not consider this possibility.

Cleft palate repair in this study was performed by the von Langenbeck technique, which accounts for nearly all palatoplasties performed at the institution, similar to other studies (Bertier et al., 2007; Billmire, 2008; Agrawal, 2009).

Some authors state that the ideal age for palate repair is around 12 months of age (Gunther et al., 1998; Helling et al., 2006; Andersson et al., 2008; Khosla et al., 2008; Phua and Chalain, 2008) or between 12 and 14 months (Chait et al., 2002; Bertier et al., 2007). The American Cleft Palate-Craniofacial Association (1993) recommends lip repair in the first 12 months of life and primary palatoplasty up to 18 months.

In the present sample the age at which the individuals underwent primary palatoplasty ranged from 12 to 36 months. Most individuals (84.38%) had primary palatoplasty performed at the age of 12 to 24 months, which includes the ideal period proposed by the American Cleft Palate-Craniofacial Association (up to 18 months) and extends 6 months beyond that. However, there was no statistically significant association between the prevalence of fistula and the age at palate repair (P = .148).

A statistically significant association (P = .019) suggests the surgeon's skill influences the surgical outcomes achieved. Some reports corroborate this statement, mentioning that surgeons who operate occasionally are subject to greater occurrence of fistula because of lower professional performance (Cohen et al., 1991; Emory et al., 1997; Losken et al., 2011). However, other studies did not observe a relationship between the plastic surgeon's skill and the occurrence of fistula (Muzaffar et al., 2001; Parwaz et al., 2009; Landheer et al., 2010). The institution where this study was conducted performs 150 to 200 surgeries for cleft repair per month on average. All surgeons had 15 to 20 years of clinical experience on average and the sample distribution among the surgeons was highly variable.

The intraoperative problems present in 40% of the sample presented statistically significant associations with the presence of fistula (P = .003). Among all problems, a statistically significant association was observed for the presence of fistulas in cases with occurrence of mucosal tear (P = .02), suture under tension (P = .01), large tissue displacement at the site of palate closure (P = .02), and formation of dead spaces (P = .003).

The literature does not address the occurrence of specific problems during surgical procedures, probably due to the lack of information of retrospective studies that show failures in the record at all stages of rehabilitation. In the institution where the study was conducted, plastic surgeons are expected to routinely record occasional intraoperative problems in a specific form in the record, as well as the procedure used to solve them. Any postoperative problems are reported by the nursing staff, which describes the occurrences and refers the patient to the responsible surgeon who will offer the needed assistance, either during hospitalization or later. Data in the present study were only available due to this standardized routine.

The postoperative problems present in 218 (37%) individuals of this sample may have influenced the surgical outcomes obtained in different manners, especially considering the mediate events (occurring 2 hours or more after completion of surgery), in which statistically significant associations were observed with the prevalence of fistula (P = .000002). Apparently, it seems that immediate problems (P = .903) were not as harmful, possibly because they occurred in a hospital environment and were better addressed. In contrast, mediate problems probably occurred when the patient was no longer under care at the hospital and may have been caused by inadequate care by the caretaker.

The present study revealed that postoperative problems related to hemorrhage (P = .015), fever (P = .0003), and airway pathologies (P = .0002) presented positive statistical association with the presence of fistula. Considering the occurrence of fever and airway pathologies, it may be inferred that the presence of infection in the postoperative period, with probable damage to an individual's immune system, affects the healing process of the palate.

The occurrence of palatal necrosis (P = .0042) in three individuals in the sample, described in the records as occurring immediately after completion of the surgical procedure, led to formation of palatal fistula.

The prevalence of palatal fistulas after primary palatoplasty observed in this sample, 27% of patients, is similar to data in the literature, with values ranging from 2% to 45% (Berkman, 1978; Åbyholm et al., 1979; Amaratunga, 1988; Cohen et al., 1991; Emory et al., 1997; Gunther et al., 1998; Wilhelmi et al., 2001; Yu et al., 2001; Bresnick et al., 2003; LaRossa et al., 2004; Inman et al., 2005; Helling et al., 2006; Diah et al., 2007; Smith et al., 2007; Phua and Chalain, 2008; Agrawal, 2009; Parwaz et al., 2009; Landheer et al., 2010; Losken et al., 2011).

Though the prevalence found in our study was concerning, it is difficult to compare with values in the literature because of the lack of standardized studies, related to the sample size; definition of what should be considered a fistula; and how to classify fistulas, name them, or even consider their location.

The present study considered the following location of fistulas: anterior region of the palate, medium region of the palate, and transition between hard and soft palate, revealing greater occurrence (37.11%) at the anterior region, followed by the medium region (32.08%) and transition between hard and soft palate. These regions are also reported in the literature as the most prevalent, mentioning the anterior region of the hard palate (Musgrave and Bremner, 1960; Åbyholm et al., 1979; Di Ninno, 2000; Muzaffar et al., 2001; Smith et al., 2007; Losken et al., 2011), medium region of the hard palate (Cohen et al., 1991), and transition between hard and soft palate (Amaratunga, 1988; Helling et al., 2006; Parwaz et al., 2009), the latter considered more susceptible to fistulas due to the greater tissue tension because of the greater cleft width at this region (Smith et al., 2007). Data on the size or shape of fistulas were not considered because of lack of information in the records for most individuals in the sample.

The continuous evaluation of treatment outcomes (Smith et al., 2007; Phua and Chalain, 2008) allows comparison with other centers in the search for best protocols with a minimum number of interventions and complications for the patients. However, the different evaluation methods found in the different centers precluded a comparison with the present results, because it is known that the clinical outcomes are strongly influenced by several variables in data collection, as well as by the different surgical protocols employed.

Determining the prevalence of palatal fistulas, which may limit and interfere with the function and quality of life of individuals with cleft lip and palate, is fundamental to allow the professional staff to assess its own outcomes. It allows a conscious and responsible evaluation of the care being delivered and the adequacy of the protocol if necessary, benefiting the several specialties involved in the rehabilitation of cleft lip and palate. It allows the reduction of costs for the hospital by reducing the number of secondary surgeries and consequently the anesthetic-surgical risk, as well as assuring the correct standardization and adequacy of the quality of treatment offered to the patients.

Conclusions

Considering the present results, the following could be concluded:

The prevalence of palatal fistula after primary palate repair in individuals with complete unilateral cleft lip and palate in this study was 27%.

Analysis of the causal factors showed positive associations between the prevalence of fistula and a.

initial wide and regular cleft width;

intraoperative problems, characterized by mucosal tearing, large tissue displacement, suture under tension, and formation of dead spaces;

postoperative problems, characterized by hemorrhage, fever, airway pathologies, and tissue necrosis;

surgeon's skill.

The anterior region of the palate had a greater occurrence of fistulas.

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