Unilateral Cleft Lip Repair

Unilateral cleft lip is a common craniofacial anomaly, and its repair is a complex but often successful surgical procedure aimed at restoring both function and aesthetics. This comprehensive guide, drawing from extensive clinical experience, will break down the essential aspects of unilateral cleft lip repair, covering everything from initial diagnosis to advanced surgical techniques and long-term outcomes, ideal for students seeking to understand this vital medical process.

Understanding Unilateral Cleft Lip: A Comprehensive Overview

The effective treatment of unilateral cleft lip necessitates a multidisciplinary approach. This involves a team of specialists including surgeons, orthodontists, speech pathologists, pedodontists, prosthodontists, otolaryngologists, social workers, psychologists, and a photographer, all coordinated by a dedicated center coordinator. This integrated approach ensures comprehensive care for cleft patients from infancy through adulthood, addressing psychological, aesthetic, functional, and spiritual development.

Basic Science and Disease Process: Unilateral Cleft Lip Genetics

Prenatal Diagnosis of cleft lip is typically made after 16–20 weeks’ gestation using ultrasound. Advances in three-dimensional ultrasonography allow for more accurate visualization, which is invaluable for prenatal counseling. Surgeons use these images to provide information to parents regarding treatment protocols and expected outcomes.

The genetics of orofacial clefting are still partially understood but are crucial for counseling affected families. Isolated cleft palate is considered genetically distinct from unilateral cleft lip, with or without cleft palate. Both genetic and epigenetic factors contribute, evidenced by varying incidence rates across different ethnicities, geographic locations, and socioeconomic conditions. Twin studies confirm a strong genetic basis, with a 43% concordance rate in monozygotic twins versus 5% in dizygotic twins.

Incidence varies by ethnicity, with Amerindian populations showing the highest rate (3.6 per 1000 births) and African-Americans the lowest (0.3 per 1000 births). In white newborns, the incidence is approximately 1 in 1000. While over 250 syndromes are associated with orofacial clefting, most cases are nonsyndromic. Cleft lip/palate favors boys and affects the left side more often.

Recurrence risks for unaffected parents with one affected child are about 4%, increasing to 9% with two affected children. If one parent is affected, the risk is 4%, rising to 17% if both a parent and a child are affected. The risk also increases with the severity of the cleft.

Several candidate genes have been linked to cleft lip/palate, including transforming growth factor-α (TGFA), transforming growth factor-β3 (TGFB3), retinoic acid receptor-α (RARA), homeobox gene MSX1, and BCL3 proto-oncogene. However, interpreting these associations requires caution due to potential false-positives and the complex interplay of genes and environment.

Classifying Unilateral Clefts: A Numeric Approach

Historically, Veau classified clefts into four groups. However, a more accurate numeric system, modified from Kernahan's Y classification, is now widely used. This system assigns numbers (1–5 or 11–15 for the primary palate; 6–9 or 16–19 for the secondary palate) to specify left or right clefts and their extent. A letter coding system (e.g., LPC for Left Primary Complete) also simplifies communication and sorting.

Diagnosing and Selecting Patients for Unilateral Cleft Lip Repair

Diagnosis and patient selection involve simple anthropometric measurements with calipers to assess soft tissue deficiencies accurately. Surgeons also make an overall impression of cleft width, alar cartilage distortion, soft tissue deficiencies (including orbicularis muscle thickness), and underlying bony framework. Three-dimensional computed tomographic scans can record bone deficiencies in the maxilla and alveolus, although this is not always practical. These evaluations reveal a wide spectrum of bone and soft tissue deficiencies, supporting the concept that all clefts are unique.

Key areas of concern for surgeons include the amount of tissue medial to the ala base, the vertical height of the lateral lip, and the horizontal length of the lateral lip. Careful evaluation of skin lateral to the columella and medial to the alar base is also critical to prevent complications like a small nostril.

Surgical Techniques for Unilateral Cleft Lip Repair

The overall treatment plan, as practiced at centers like the Chang Gung Craniofacial Center, begins with prenatal diagnosis and pediatric evaluation at birth. Parents receive counseling on feeding and subsequent care. Presurgical nasoalveolar molding starts early, typically at 2 weeks of age.

Presurgical Alveolar and Nasoalveolar Molding: Preparing for Unilateral Cleft Lip Repair

Presurgical orthopedics aims to correct skeletal deformities of the cleft maxilla before surgery. This involves keeping the tongue out of the cleft and replacing the pulling force of separated lip muscles with tape traction. Techniques include:

• External Taping with or without Dental Plate: The simplest method, using Micropore tape to approximate upper lips and reposition maxillary segments. A dental plate keeps the tongue out of the cleft and prevents arch collapse.
• Liou’s Method: Utilizes a molding bulb attached to a dental plate to mold the nose simultaneously with external taping. The device is adjusted every 1–2 weeks for about 3 months.
• Grayson’s Method: Performs nasal molding after alveolar approximation to prevent overstretching nasal cartilage. The appliance includes an acrylic plate for the maxillary arch and a nasal stent. This method also requires careful monitoring every 1–2 weeks for 3–6 months.

Presurgical nasoalveolar molding significantly improves nasal shape and narrows the cleft, facilitating surgical reconstruction.

Adhesion Cheiloplasty: A Two-Stage Unilateral Cleft Lip Repair

An adhesion cheiloplasty is a preliminary procedure that changes a complete cleft into an incomplete one, often followed by a definitive cheiloplasty around 6 months later. It is indicated for wide alveolar clefts (>12–15 mm) or significant vertical height discrepancies. While it can narrow the cleft and decrease tension, its use has decreased due to improved presurgical orthopedics and single-stage techniques.

Surgical Technique for Adhesion Cheiloplasty:

1. Markings: Similar to complete unilateral clefts, but vital landmarks like CPHL and CPHL′ must be preserved.
2. C-flap and Mucosal Flap Elevation: Incisions on the noncleft side lip create a mucosal C flap, based on the premaxilla, which is rotated and inserted behind the columella to mobilize the medial lip.
3. Lateral Lip Incisions: The free edge of the lateral lip is opened, preserving vermillion medial to CPHL′. Fibrous attachments between the lower lateral cartilage (LLC) and piriform rim are released.
4. Mucosal Flaps: A turbinate (T) flap and buccal mucosal (B) flap are elevated. The T flap is rotated to the piriform rim, and the buccal flap is folded and sutured to its edge.
5. Nostril Floor Closure: The folded buccal flap is advanced and sutured to the premaxilla periosteum. Buccal lip mucosa is advanced and sutured for complete mucosal closure.
6. Muscle and Skin Closure: Interrupted horizontal sutures secure the muscle, and skin is closed. No dissection between nasal skin and LLC dome is performed.

Rotation Advancement Cheiloplasty for Complete Unilateral Clefts

This technique involves several key principles for optimal correction, including Mohler’s rotation incision, mucosal flaps for nasal floor reconstruction, and muscle reconstruction to simulate the philtral column.

Key Surgical Concepts:

• Mohler’s rotation incision: A curving line from CPHL upward to the columella base, mimicking the philtral ridge.
• Mucosal flaps: Used for nasal floor reconstruction and correcting piriform area mucosal deficiency.
• Eliminating perialar incision: Limits scars around the ala base and nostril floor.
• Mobilization of alar base: Releases fibrous attachments of the LLC to the maxilla and ULC.
• Nasal floor reconstruction: Achieved with complete mucosal closure using L-flaps and T-flaps.
• Muscle release and reconstruction: Orbicularis peripheralis muscle is dissected, and abnormal paranasal muscle insertions are released. Muscle is approximated with overlapping mattress sutures to simulate a philtral column and anchored to the nasal septum to centralize the Cupid’s bow.
• Triangular vermillion flap: From the lateral lip, corrects central vermillion deficiency beneath the Cupid’s bow.
• Semi-open rhinoplasty: Uses a reverse U incision on the cleft side and a rim incision on the noncleft side for better visualization and repositioning of cartilages.
• Atraumatic dissection: To release fibrofatty tissue from LLCs.
• Advancement and fixation of LLC: The cleft side LLC is advanced and fixed to the noncleft side LLC and skin in an over-corrected position.
• Alar transfixion sutures: Define the alar-facial groove.

Detailed Steps for Unilateral Cleft Lip Repair:

1. Medial Incisions: Mohler’s rotation incision is marked. Adequate rotation ensures Cupid’s bow leveling. Back-cuts are avoided to prevent wide defects.
2. C-flap and Medial Crura: C-flap incisions extend along the skin-mucosa junction. Blunt-tip scissors release the footplate of the medial crura of the cleft side LLC.
3. Lateral Lip Incisions: An L-flap is marked based on the maxilla, preserving vermillion on the lateral lip. A triangular WSR (white skin roll) flap is designed.
4. L-flap and Inferior Turbinate Flap: An inferior turbinate (T) flap is elevated. Both L and T flaps allow mobilization of the LLC and lateral lip.
5. Orbicularis Muscle Dissection and Alar Base Mobilization: Orbicularis peripheralis muscle is released subdermally, releasing abnormal insertions of paranasal muscles from the alar base.
6. Elevation of Orbicularis Marginalis Flap: The OM flap (including muscle, vermillion, and mucosa) is elevated to its base beneath CPHL′.
7. Correction of Piriform Deficiency: LLC is repositioned and fixed to the ULC. The T-flap is rotated to fill the piriform rim defect.
8. Nasal Floor Reconstruction and Alar Base Repositioning: The L-flap is rotated medially and attached behind the columella. C-flap mucosa is rotated laterally and attached to the maxilla, providing mucosal coverage. The vestibular skin with the attached ala is advanced over the mucosal bridge.
9. Muscle Reconstruction: A key suture centralizes the Cupid’s bow, anchoring the lateral muscle to the nasal septum. Lateral muscle overlaps the medial muscle to simulate a philtral column.
10. Philtral Column Reconstruction: Mohler’s incision line, overlapping muscle sutures, and preserved skin laxity contribute to a bulging philtral column.
11. Incisions for Triangular Vermillion Flap: A triangular vermillion flap is incised from the OM flap to correct vermillion deficiency beneath the Cupid’s bow.
12. Closure of Free Border: Points CPHL and CPHL′ are approximated. Excess mucosa is trimmed, and the vermillion triangular flap is inserted. Incisions are closed with fine sutures.
13. Nasal Floor Incisions: Made to vertically lengthen the lip and level the alar base/Cupid’s bow. The nasal sill is carefully preserved.
14. Final Skin Closure: Advancement flap tip sutured, excess nostril floor skin excised, and lip skin closed. A small triangular WSR flap reconstructs the white skin roll.
15. Semi-Open Rhinoplasty: Reverse U incision on the cleft side and rim incision on the noncleft side. Fibrofatty tissue is released from LLCs, which are approximated with mattress sutures and over-corrected. Excessive skin below the reverse U incision is trimmed.
16. Alar Base Position: Abnormally attached paranasal muscles are released, and the alar base is advanced medially.
17. Alar-Facial Groove Creation: Alar transfixion sutures define the groove and address vestibular webbing.

Rotation Advancement Cheiloplasty for Incomplete Clefts

Incomplete clefts can be challenging, often misjudged as having a