Jan 24: Cleft Lip/Cleft Palate (updated 08/06) Jan 24: Cleft Lip/Cleft Palate (updated 08/06) Preceptor: ; Vacation Scott

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1 Jan 24: Cleft Lip/Cleft Palate (updated 08/06) Preceptor: ; Vacation Scott 1. (Amy) Discuss the incidence, causes and genetic aspects of cleft lips and palates (CL and CP). Cleft lip/palate deformities are the most common genetic anomalies in the head and neck. Cleft lip occurs in 1/1000 live births in the United states, while cleft palate occurs in 1/2000 live births. Cleft lip is more common in Asians ( 2.1/1000) and Native Americans (3.6/1000), and it is least common in blacks (0.41/1000). Cleft palate does not vary in incidence between ethnic groups and occurs in 0.5/1000 births. Males have more cleft lips (2:1), but females have more cleft palates (2:1). This is likely related to the palatine shelves fusing 1 week later in girls than in boys. Recurrence risks of having a child with CL/P are useful in counseling parents. Two unaffected parents with a child with CL/P have a 4.4% chance of having another child with a CL/P and a 2.5% chance of having a child with isolated CP. One parent with a cleft has a 3.2% and 6.8% chance of having a child with CL/P or isolated CP, respectively. Cleft lips and cleft palates are influenced by both genetic and environmental factors, and both may be either syndromic or nonsyndromic. Syndromic clefts may be transmitted by a single gene that is autosomal-dominant, autosomal-recessive, or X-linked. Approximately 70% of CL/P are thought to be nonsyndromic, while 50% of CP are nonsyndromic. Greater than 200 syndromes are associated with facial clefts. van der Woude syndrome: autosomal dominant, CL/P, most common syndrome associated with CL, lower lip pits Sickler Syndrome: autosomal dominant, cleft palate, retinal detachment, cataracts, early arthritis Treacher Collins symdrome: autosomal dominant, malformation of the malar and other facial bones, eye lid colobomas, middle ear ossicular abnormalities Apert Syndrome: autosomal dominant, cleft palate, acrocephaly, fused digits, stapes fixation Pierre Robin Sequence: micrognathia, cleft palate, glossoptosis Teratogens: ethanol, thalidomide, tobacco smoke, phenytoin, retinoic acid Environmental: maternal diabetes, amniotic band syndrome 2. (Dara) Review the normal embryologic development of the lip and palate. The primary and secondary palates are delineated according to embryological development. The primary palate or premaxilla is a triangular area of the anterior hard palate extending from anterior to the incisive foramen to a point just lateral to the lateral incisor teeth. It includes that portion of the alveolar ridge containing the four incisor teeth. The secondary palate consists of the remaining hard palate and all of the soft palate. The primary palate forms during the 4th to 7th weeks of gestation as the two maxillary swellings merge and the two medial nasal swellings fuse to form the intermaxillary segment. The intermaxillary segment is composed of a labial component (forms the philtrum), a maxilla component (forms alveolus and 4 incisors), and palatal component (forms the triangular primary palate). Normally during development of the primary palate, a cleft does not exist (unlike the secondary palate in which cleft formation occurs as a natural stage of development). The secondary palate forms during the 6th to 9th weeks of gestation, as the palatal shelves change from a vertical to horizontal position and fuse. The tongue must migrate away from the shelves in an anteroinferior direction for palatal fusion to occur. 3. (Dara) Describe the abnormal development leading to CL and CP. Patients with clefts have a deficiency of tissue and not merely a displacement of normal tissue. A cleft lip occurs when an epithelial bridge fails, due to lack of mesodermal delivery and proliferation from the maxillary and nasal processes. Clefts of the primary palate occur anterior to the incisive foramen. Clefts of the secondary palate are due to lack of fusion of the palatal shelves, and always occur posterior to the incisive foramen. The secondary palate closes 1 week later in females, which may explain why isolated clefts of the secondary palate are more common in females. A cleft of the lip increases in probability of a cleft palate developing. The cleft of the lip occurs earlier and inhibits tongue migration, which may then prevent horizontal alignment and fusion of the palatal shelves. In the unilateral cleft lip, the floor of the nose communicates freely with the oral cavity, the maxilla on the cleft side is hypoplastic, the columella is displaced to the normal side, and the nasal ala on the cleft side is laterally, posteriorly, and inferiorly displaced. The lower lateral cartilage of the nose is lower on the cleft side, its lateral cruz is longer, and the angle between the medial and lateral cruz is more obtuse. The muscles of the orbicularis oris do not form a complete sphincter but instead are directed superiorly to the ala nasi laterally and the base of the columella medially. In the bilateral cleft lip, the central portion of the alveolar arch is rotated anteriorly and superiorly. The medial or prolabial segment of skin contains no muscle or vermillion. In palatal clefts, the muscles of the soft palate are hypoplastic and insert in the posterior margin of the remaining hard palate rather than the midline raphe. Associated dentition abnormalities include supernumerary teeth (20%), dystrophic teeth (30%), congenitally missing teeth (50%), and malocclusion (almost 100%). 4. (Deya) Review the classification of CL and CP. A variety of classification systems have been proposed, but few have wide clinical acceptance. Embryologic development serves the foundation for a number of the classification systems. 1/5

2 I. Veau classification: a. Group 1: soft palate only b. Group 2: clefts of the soft & hard palate reaching anteriorly as far as the incisive foramen. c. Group 3: includes complete unilateral alveolar clefts that generally involve the lip as well. d. Group 4: includes bilateral alveolar clefts, which are often also associated with bilateral clefts of the lip II. More detailed classification systems exist similarly based on embryologic development. a. CL classified as unilateral or bilateral, and its extent may be classified as: 1. Complete: entire vertical thickness of the upper lip and is often a/w alveolar cleft 2. Incomplete: involves only a portion of the vertical height of the lip, with a variable segment of continuity across the cleft region (Simonart's band {see pic}) b. CP are described as being unilateral or bilateral, and their extent may be classified as complete or incomplete. In addition, CPs are classified according to their location relative to the incisive foramen. 1. Clefts of primary palate occur anterior to the incisive foramen 2. Clefts of the secondary palate occur posterior to the incisive foramen 3. Unilateral clefts of the secondary palate are defined by a cleft in which the palatal process of the maxilla on one side is fused with the nasal septum. 4. Bilateral complete cleft of the secondary palate have no point of fusion between the maxilla and the nasal septum 5. Incomplete CP usually involves the secondary palate only and has varying degrees of severity with the least severe incomplete cleft being a sub-mucous CP in which the underlying palatal musculature is deficient and inappropriately attached (a/w bifid uvula, a zona pellucida (blue-colored midline region representing the muscle deficiency), and a notch in the posterior hard palate) 5. (Deya) What speech sounds to CL and CP kids have difficulty with? What is the treatment? Is it successful? The velopharynx is an important part of speech production. The velopharyngeal port closes mainly as a result of the levator veli palatini moving the velum in a posterior superior direction. Additionally, medial movement of the lateral pharyngeal walls & occasional anterior movement of the posterior wall contribute to closure. If a cleft of the hard or soft palate exists, velopharyngeal insufficiency leads to free flow of air into the nose during speech. Errors in articulation are common in cleft palate patients, especially those involving affricates and fricatives: 1. Affricate (aka affricative) a speech sound comprising occlusion, plosion or stop (a consonantal speech sound produced by closing off the oral cavity and then releasing with a burst of air, such as an initial), and frication, as either of the ch-sounds in church and the j-sound in joy. 2. Fricative - of speech sounds produced by forcing air through a constricted passage (as `f', `s', `z', or `th' in both `thin' and `then') In addition, velopharyngeal incompetence is associated with an audible escape of air from the nose during production of pressure sounds and is termed nasal emission or snort. It is estimated that 75% of patients have velopharyngeal competence following primary cleft palate surgery. If velopharyngeal dysfunction persists, the following treatment options exist: 1. Speech therapy: used to develop compensatory strategies to improve the general quality and intelligibility. Generally not appropriate if a structural abnormality exists such as a cleft palate, but may be utilized after surgical correction if speech deficits continue. 2. Prosthetic treatment: an obturator (speech bulb prosthesis) places a round piece of acrylic into the velopharynx so the movement of the walls of the velopharynx will achieve closure as they contact the obturator. 3. Surgery (90-95% of pts have velopharyngeal competence with directed secondary procedures): a. Intraveolar veloplasty - attempt to improve function by reorienting the levator b. Furlow double-opposing Z-plasty - attempt to improve function by reorienting the levator while also thickening and lengthening the palate. c. Sphincter pharyngoplasty - borrows lateral wall tissue to obturate the lateral and posterior walls. Bilateral myomucosal flaps are elevated from the lateral pharyngeal wall to be inserted into an incision on the posterior nasopharyngeal wall at the level of greatest closure. 2/5

3 d. Superiorly based pharyngeal flap - borrows tissue from the posterior wall to obturate the middle portion of the velopharynx. e. Posterior pharyngeal wall augmentation - in the child who has a very small posterior midline "gap" that causes the velopharyngeal dysfunction, one can consider augmentation of the posterior pharyngeal wall. Although many things have been tried including hyaluronic acid, fat, Teflon, and cartilage - most have limited long-term success. 6. (Josh) When do you do a lip adhesion? How do you do it? PRS 1997;100:567. Lip adhesion may be performed in within the first few days and weeks of life as a preliminary procedure, with definitive repair delayed to a later date. The purpose of a lip adhesion is to convert a a wide complete cleft to an incomplete cleft and allow tissue growth during the delay phase and to provide additional reconstructive tissue. The principle advantage of lip-adhesion is molding the alveolar segments to a more favorable position before repair of the unilateral cleft lip. A 6- to 8-mm incision, 1 mm below the vermilion-cutaneus junction, was marked on each side of the cleft. On the lateral lip element, another incision was placed that extends from the lower intercartilaginous line (vestibular-skin junction) and into the lateral gingivolabial sulcus, perpendicular to the adhesion incision. By dissection in the supraperiosteal plane, the lateral lip element was freed off the maxilla until it could be easily approximated to the medial labial element. Scissors dissection between the medial crura and above the slumped alar cartilage created a pocket so that the genu would bow upward as the lateral lip element was opposed to the medial side. Vestibular lining was not dissected from the alar cartilage. The lateral lip element was advanced medially, and the sulcus and posterior mucosal layer of the adhesion were closed with chromic sutures. Three to four polydioxanone sutures were placed to approximate the muscle layers, but the muscle was not dissected from the cutaneous-mucosal envelope on either side of the cleft. Interrupted 7-0 chromic sutures were used to appose the anterior (vermilion) layer of the adhesion. If supra-alar dissection alone did not result in adequate convexity of the alar dome, a buried suspension suture was used to elevate the alar cartilage to the ipsilateral upper lateral cartilage. 7. (Dave) Discuss the role of orthodontics in the management of CL and CP. Dental abnormalities in CL/P can arise from embryological or post-surgical reasons. Embryological: - Cleft lip alone usually have normal teeth - Complete cleft extending throught the alveolus impairs incisor development; lateral incisors on affected side are generally absent, ectopic, diminutive, or represented by two small conical teeth in each cleft margin. The adjacent central incisor inclines toward the cleft and may have a marked curvature. The central incisor may also be small or absent. - Complete bilateral clefts cause the premaxilla to be situated too far forward beyond the tip of the nasal septum, causing prominence of the incisal area. Surgical: - Transverse disturbance: Lip repair may cause rapid narrowing of anterior arch by approximation of divided segments. After palate repair, scar tissue may inhibit widening of the maxillary arch and cause increased tendency toward crossbite - Anteroposterior disturbance: Post-op palatal scar tissue may restrain the normal downward and forward translation of the maxilla that occurs during growth by binding it to the sphenoid bone at the pterygoid processes. In severe cases, and particularly with complete unilateral clefts, this can cause maxillary retrusion and class III incisor relationship which progressively worsens as the rest of the face grows. - Vertical disturbance: Can worsen the apparent severity of the class III incisor relationship. Treatment: The first phase of treatment usually starts as permanent teeth start to erupt. Orthopalatal expansion is done using an expander to round out the the upper alveolus and widen the maxilla. This may be followed by an alveolar bone graft. After all the permanent teeth have erupted, the second phase may involve extracting extra teeth, dental implants if teeth are missing, or applying braces. 3/5

4 About 25% of children with unilateral cleft lip and palate have maxillary retrusion, and orthognathic surgery may be necessary, usually an osteotomy with distraction of the maxilla. This may require another bone graft for stability. 8. (Kathy) You are called to the NICU to counsel parents of a newborn with a unilateral CL and CP. What do you tell them about the timing of repair of each. Also, the baby is having problems with feeding. Any suggestions? For timing of cleft lip repair we follow o The rule of tens as prerequisites: Ten weeks of age. Weight of ten pounds. Hemoglobin of ten. o However, if presurgical manipulation of alveolus or premaxilla is required, lip repair should be delayed until this is done. For timing of cleft palate, the overriding concern is speech, but these children also have difficulty with sucking effectively. o Usually repaired between months of age, but earlier repair now has been supported by data and results in a decrease in compensatory articulations. Oral intake in children with cleft palate can be compromised by their inability suck effectively. It is important to instruct the parents on how to use a cleft nurse. There are a variety of types, all of which require less effort than a normal bottle. Even a crosscut nipple on a regular bottle may work in these cases. Most of the bottles require some squeezing as well to supplement flow. 9. (Tali) Draw: 2 unilateral cleft lip repairs, 1 bilateral cleft lip repair and 2 cleft palate repairs. Don t put names on them. Pass them out and have everyone label. Unilateral Cleft Repair: 2 techniques 4/5

5 Bilateral cleft lip repair: 1 technique Cleft Palate repair: 2 techniques 10. (CY) Analyze the nasal deformity associated with CL. How do you fix it? Classic board question: 1. septum deviates toward cleft side (usually outside maxillary crest) 2. medial crus of the ala on the cleft side is displaced posteriorly and inferiorly 3. nasal tip deviate away from the cleft side Principles of primary nasal correction include the following: Wide undermining of the nasal skin on the cleft side, freeing the skin from the underlying nasal skeleton Elevation of the slumped alar cartilage on the cleft side to the normal level using internal or external suspension sutures Medial advancement of the lateral crus and alar base on the cleft side 11. (CY) Why do cleft kids have eustachian tube dysfunction? How do you manage their ear disease? Normally the tensor and levator muscles insert into the midline aponeurosis of the velum. In cleft palate, the levator attaches anteriorly to the hard palate and often is hypoplastic, and the tensor may end at the hamulus, or insert into the lateral velum. This leads to ET dysfunction Manage with ETT tubes. **In a landmark article in 1971, Bluestone compared the Eustachian tube function of patients with unrepaired cleft palate and normalpalate patients with a history of serous otitis. Although both groups demonstrated evidence of Eustachian tube dysfunction, the cleft palate patients had a "functional" obstruction of the tube at the nasopharyngeal end--as opposed to the "mechanical" obstruction found in serous otitis patients. 5/5