Utilization of the Labial Flap in Anterior Palatal Fistula Repair

Cleft lip and palate characterize the most common congenital facial malformations in the US, occurring in approximately 1 in 600 live births.¹ Although controversial, cleft palate surgery is usually performed around 9 to 18 months of age to restore separation of the oral and nasal cavities and assist in normal speech development while limiting impact of maxillary growth. Palatal fistulas are the most common postoperative complications in primary palatoplasty, with incidence rates ranging from 10% to 30% depending on severity of clefts, surgical techniques, and age of repair.² Functional indications for repair of these fistulas include food regurgitating from the nose, food impaction resulting in malodor, and hypernasality with speech. In a retrospective analysis, almost 66% of post palatoplasty fistulas were found to be anterior palatal fistulas (APFs).³ Probable cause for occurrence of APF is anatomically shorter lesser segment, wide palatal cleft defect with thin palatal shelves, improper reflection of subperiosteal flap, and improper closure.

APFs present a difficult reconstructive problem due to lack of available local tissue. Variety in presentation requires multiple different closure techniques, including local flaps (alveolar mucoperiosteal flaps and buccal mucosal flap), tongue flaps, and 2-flap palatoplasty. The choice of reconstruction is usually governed by the defect size as well as quality of surrounding native tissue.³ Of the wide array of APF closure techniques, one of the most successful in reconstruction is a 2-layer technique described by Abdel-Aziz et al, who observed a 91% success rate across 33 cases.⁴ In this method, an oral mucoperiosteum hinge flap and a myomucosal flap derived from the inner surface of the superior lip were used to reconstruct the nasal and oral sides, respectively. The method utilized in this paper both validates the previously mentioned technique and provides a modification of closure of the donor site. Here, we describe a case series of 3 patients with previous failed reconstructions who underwent anterior palatal fistula repair with a random pattern labial flap.

Three patients underwent repair of an anterior palatal fistula by the cleft team at University of Mississippi Medical Center from 2020 to 2021. The patients were aged 3, 5, and 17 years and had defects measuring 2.5 × 1.5 cm, 2 × 1 cm, and 3 × 2 cm, respectively (Figure 1). In all 3 patients, the anterior palatal fistula was a complication arising after primary palatoplasty repairs.

Utilizing the labial flap for reconstruction requires a 2-stage procedure with a 3-week delay after flap closure before separation. In the first operation, the nasal cavity is closed with local turnover flaps (Figure 1B). The labial flap is elevated on the free border of the superior lip pedicled superiorly in the submucosal plane. The flap is then advanced through a gap in dentition or alveolar cleft and sutured to the posterior edge of the palatal defect, covering the oral layer of the fistula (Figure 1C). The flap is then allowed to heal for 3 weeks before separation. In the second operation, the proximal portion of the lip flap is divided, which can provide additional tissue to cover alveolar defects. A buccal mucosa graft is used to line the donor site of the flap to prevent tethering of the gingivobuccal sulcus.

The overall size of fistulas ranged from 2 cm² to 6 cm², and all 3 were located in the anterior region of the hard palate posterior to the alveolar ridge. Out of the 3 cases performed from 2020 through 2021, 2 lip flaps were successful in providing full coverage to the naso-oral fistula at the 6-month follow-up evaluation. In the 3-year-old patient, recovery was complicated by the patient not cooperating with postoperative care. At the time of the second procedure, the lip flap was found to be partially dehisced from the posterior palate, leaving a small residual fistula. At the 6-month follow-up evaluation, however, this defect was asymptomatic.

Palatal fistulas are unfortunate complications after primary palatoplasty, with recurrence rates as high as 37%. Considerations for fistula formation include both extrinsic factors, such as deficiency of palatal segment, and intrinsic factors, such as inadequate mobilization of tissue, closure under tension, difficulty with obtaining a layered closure, and postoperative bleeding and infection.² Honnebier et al separated reconstruction into 2 main categories, depending on the location and quality of tissue: local mucoperiosteal flaps (most often used in the primary palatoplasty) and regional intraoral flaps.⁵

Regarding local flaps, which have been shown to be effective when there is adequate tissue availability and relatively smaller fistula formations, Rintala et al first described repair with a double hinge flap and bone grafting procedure, achieving physiological closure in 83% of cases.⁶ Denny and Amm reported that total elevation of the palatal gingivoperiosteum was associated with a 90% success rate across 60 patients over roughly 5 years.⁷

In cases where available local tissue is compromised due to scarring or inflammation, or merely insufficient to close a fistula of a larger size, various regional flaps have proven practical alternatives to local tissue. Lehman et al demonstrated this concept in 1978, performing closure of APFs with buccal mucosal flaps and bone grafts for bony defects in 19 patients.⁸ In similar fashion, Nakakita et al also utilized the buccal musculomucosal flap but only achieved closure of 36% across 42 patients when the palate involved an APF.⁹ Tiwari and Sarabahi utilized the orbicularis oris musculomucosal flap with a success rate of 92% across 25 patients, stating this flap has a more defined blood supply and no donor site morbidity.¹⁰ Using tissue from the tongue has likewise shown favorable outcomes, as Assunçao’s employment of the tongue flap technique demonstrated an 100% flap survival rate and roughly an 8% recurrence rate in fistula across 12 patients.¹¹ In contrast, Sohail et al demonstrated the efficacy of the facial artery myomucosal (FAMM) flap over techniques utilizing tongue tissue, with successful results in terms of speech and eating in 12 of 16 FAMM flap procedures compared with none of 23 patients undergoing tongue flap procedures.¹² Whereas the FAMM flap has been suggested for its strengths in decreasing operating time and postoperative complications,¹² concerns remain regarding speech, eating, and adequate venous drainage.¹³

The musculocutaneous labial flap (Figure 2) can provide an effective closure with minimal donor morbidity. In addition, this strategy is associated with minimal postoperative limitations compared with a tongue flap, which restricts speech, and a buccal or FAMM flap, which restricts mouth opening for prolonged periods. Although this case series examined a small sample of patients, results were comparable to the successful outcomes reported by Abdel-Aziz et al and further substantiate the random pattern labial flap approach.⁴ In addition, the method used at our center modifies their technique to utilize a buccal mucosa graft at the donor site to prevent gingivobuccal sulcus tethering.

In this case series, all 3 patients had previous palatal reconstructions that resulted in anterior palatal fistulas. While the labial flap is not a substitute for traditional palatal revisions with re-elevated mucoperiosteal flaps, it remains a dependable option for difficult reconstructions. Specifically, in isolated anterior palatal fistulas that may have failed a previous closure attempt, and in presence of alveolar cleft, this technique can prove useful. Said validation is supported by complete naso-oral fistula coverage observed in two of the 3 patients in this case series, with the remaining patient still achieving an asymptomatic result despite suboptimal outcome.

Anterior oral nasal fistulas are common postoperative complications in patients with primary palate repairs, and they present difficult reconstructions due to lack of local tissue flaps. For the 3 patients described in this case series, a 2-stage method utilizing a random pattern labial flap was used to provide oral fistula coverage. We recommend this procedure when multiple prior traditional attempts at closure have been performed unsuccessfully and the patient is mature enough to understand the procedure and comply with postoperative care.

Affiliations: Department of Plastic and Reconstructive Surgery, University of Mississippi Medical Center, Jackson, MS

Correspondence: Ian C. Hoppe, MD; ihoppe@umc.edu

Disclosures: The authors declare no conflicts of interest.