Cleft lip and cleft palate, also known as orofacial cleft, is a group of conditions that includes cleft lip (CL), cleft palate (CP), and both together (CLP).A cleft lip contains an opening in the upper lip that may extend into the nose. The opening may be on one side, both sides, or in the middle. A cleft palate is when the roof of the mouth contains an opening into the nose. These disorders can result in feeding problems, speech problems, hearing problems, and frequent ear infections. Less than half the time the condition is associated with other disorders.
Cleft lip and palate are the result of tissues of the face not joining properly during development. As such, they are a type of birth defect. The cause is unknown in most cases.Risk factors include smoking during pregnancy, diabetes, obesity, an older mother, and certain medications (such as some used to treat seizures). Cleft lip and cleft palate can often be diagnosed during pregnancy with an ultrasound exam.
A cleft lip or palate can be successfully treated with surgery. This is often done in the first few months of life for cleft lip and before eighteen months for cleft palate. Speech therapy and dental care may also be needed. With appropriate treatment, outcomes are good.
Cleft lip and palate occurs in about 1 to 2 per 1000 births in the developed world. CL is about twice as common in males as females, while CP without CL is more common in females. In 2013, it resulted in about 3,300 deaths globally, down from 7,600 deaths in 1990. The condition was formerly known as a "hare-lip" because of its resemblance to a hare or rabbit, but that term is now generally considered to be offensive.
If the cleft does not affect the palate structure of the mouth, it is referred to as cleft lip. Cleft lip is formed in the top of the lip as either a small gap or an indentation in the lip (partial or incomplete cleft), or it continues into the nose (complete cleft). Lip cleft can occur as a one-sided (unilateral) or two-sided (bilateral) condition. It is due to the failure of fusion of the maxillary and medial nasal processes (formation of the primary palate).
A mild form of a cleft lip is a microform cleft.A microform cleft can appear as small as a little dent in the red part of the lip or look like a scar from the lip up to the nostril. In some cases muscle tissue in the lip underneath the scar is affected and might require reconstructive surgery. It is advised to have newborn infants with a microform cleft checked with a craniofacial team as soon as possible to determine the severity of the cleft.
Cleft palate is a condition in which the two plates of the skull that form the hard palate (roof of the mouth) are not completely joined. The soft palate is in these cases cleft as well. In most cases, cleft lip is also present. Cleft palate occurs in about one in 700 live births worldwide.
Palate cleft can occur as complete (soft and hard palate, possibly including a gap in the jaw) or incomplete (a 'hole' in the roof of the mouth, usually as a cleft soft palate). When cleft palate occurs, the uvula is usually split. It occurs due to the failure of fusion of the lateral palatine processes, the nasal septum, or the median palatine processes (formation of the secondary palate).
The hole in the roof of the mouth caused by a cleft connects the mouth directly to the inside of the nose.
Note: the next images show the roof of the mouth. The top shows the nose, the lips are colored pink. For clarity the images depict a toothless infant.
A result of an open connection between the mouth and inside the nose is called velopharyngeal inadequacy (VPI). Because of the gap, air leaks into the nasal cavity resulting in a hypernasal voice resonanceand nasal emissions while talking. Secondary effects of VPI include speech articulation errors (e.g., distortions, substitutions, and omissions) and compensatory misarticulations and mispronunciations (e.g., glottal stops and posterior nasal fricatives). Possible treatment options include speech therapy, prosthetics, augmentation of the posterior pharyngeal wall, lengthening of the palate, and surgical procedures.
Submucous cleft palate (SMCP) can also occur, which is a cleft of the soft palate with a classic clinical triad of a bifid, or split, uvula which is found dangling in the back of the throat, a furrow along the midline of the soft palate, and a notch in the back margin of the hard palate.
Most children who have their clefts repaired early enough are able to have a happy youth and social life. Having a cleft palate/lip does not inevitably lead to a psychosocial problem.However, adolescents with cleft palate/lip are at an elevated risk for developing psychosocial problems especially those relating to self-concept, peer relationships and appearance. Adolescents may face psychosocial challenges but can find professional help if problems arise. A cleft palate/lip may impact an individual's self-esteem, social skills and behavior. There is research dedicated to the psychosocial development of individuals with cleft palate. Self-concept may be adversely affected by the presence of a cleft lip or cleft palate, particularly among girls.
Research has shown that during the early preschool years (ages 3–5), children with cleft lip or cleft palate tend to have a self-concept that is similar to their peers without a cleft. However, as they grow older and their social interactions increase, children with clefts tend to report more dissatisfaction with peer relationships and higher levels of social anxiety. Experts conclude that this is probably due to the associated stigma of visible deformities and possible speech impediments. Children who are judged as attractive tend to be perceived as more intelligent, exhibit more positive social behaviors, and are treated more positively than children with cleft lip or cleft palate. Children with clefts tend to report feelings of anger, sadness, fear, and alienation from their peers, but these children were similar to their peers in regard to "how well they liked themselves."
The relationship between parental attitudes and a child's self-concept is crucial during the preschool years. It has been reported that elevated stress levels in mothers correlated with reduced social skills in their children. Strong parent support networks may help to prevent the development of negative self-concept in children with cleft palate. In the later preschool and early elementary years, the development of social skills is no longer only impacted by parental attitudes but is beginning to be shaped by their peers. A cleft lip or cleft palate may affect the behavior of preschoolers. Experts suggest that parents discuss with their children ways to handle negative social situations related to their cleft lip or cleft palate. A child who is entering school should learn the proper (and age-appropriate) terms related to the cleft. The ability to confidently explain the condition to others may limit feelings of awkwardness and embarrassment and reduce negative social experiences.
As children reach adolescence, the period of time between age 13 and 19, the dynamics of the parent-child relationship change as peer groups are now the focus of attention. An adolescent with cleft lip or cleft palate will deal with the typical challenges faced by most of their peers including issues related to self-esteem, dating and social acceptance. Adolescents, however, view appearance as the most important characteristic, above intelligence and humor. This being the case, adolescents are susceptible to additional problems because they cannot hide their facial differences from their peers. Adolescent boys typically deal with issues relating to withdrawal, attention, thought, and internalizing problems, and may possibly develop anxiousness-depression and aggressive behaviors. Adolescent girls are more likely to develop problems relating to self-concept and appearance. Individuals with cleft lip or cleft palate often deal with threats to their quality of life for multiple reasons including: unsuccessful social relationships, deviance in social appearance and multiple surgeries.
Cleft may cause problems with feeding, ear disease, speech, socialization, and cognition.
Due to lack of suction, an infant with a cleft may have trouble feeding. An infant with a cleft palate will have greater success feeding in a more upright position. Gravity will help prevent milk from coming through the baby's nose if he/she has cleft palate. Gravity feeding can be accomplished by using specialized equipment, such as the Haberman Feeder, or by using a combination of nipples and bottle inserts like the one shown, is commonly used with other infants. A large hole, crosscut, or slit in the nipple, a protruding nipple and rhythmically squeezing the bottle insert can result in controllable flow to the infant without the stigma caused by specialized equipment.
Individuals with cleft also face many middle ear infections which may eventually lead to hearing loss. The Eustachian tubes and external ear canals may be angled or tortuous, leading to food or other contamination of a part of the body that is normally self-cleaning. Hearing is related to learning to speak. Babies with palatal clefts may have compromised hearing and therefore, if the baby cannot hear, it cannot try to mimic the sounds of speech. Thus, even before expressive language acquisition, the baby with the cleft palate is at risk for receptive language acquisition. Because the lips and palate are both used in pronunciation, individuals with cleft usually need the aid of a speech therapist.
Tentative evidence has found that those with clefts perform less well at language.
The development of the face is coordinated by complex morphogenetic events and rapid proliferative expansion, and is thus highly susceptible to environmental and genetic factors, rationalising the high incidence of facial malformations. During the first six to eight weeks of pregnancy, the shape of the embryo's head is formed. Five primitive tissue lobes grow:
If these tissues fail to meet, a gap appears where the tissues should have joined (fused). This may happen in any single joining site, or simultaneously in several or all of them. The resulting birth defect reflects the locations and severity of individual fusion failures (e.g., from a small lip or palate fissure up to a completely malformed face).
The upper lip is formed earlier than the palate, from the first three lobes named a to c above. Formation of the palate is the last step in joining the five embryonic facial lobes, and involves the back portions of the lobes b and c. These back portions are called palatal shelves, which grow towards each other until they fuse in the middle. This process is very vulnerable to multiple toxic substances, environmental pollutants, and nutritional imbalance. The biologic mechanisms of mutual recognition of the two cabinets, and the way they are glued together, are quite complex and obscure despite intensive scientific research.
Genetic factors contributing to cleft lip and cleft palate formation have been identified for some syndromic cases, but knowledge about genetic factors that contribute to the more common isolated cases of cleft lip/palate is still patchy.
Many clefts run in families, even though in some cases there does not seem to be an identifiable syndrome present, possibly because of the current incomplete genetic understanding of midfacial development.
A number of genes are involved including cleft lip and palate transmembrane protein 1 and GAD1, One study found an association between mutations in the HYAL2 gene and cleft lip and cleft palate formation.
In some cases, cleft palate is caused by syndromes which also cause other problems:
Many genes associated with syndromic cases of cleft lip/palate (see above) have been identified to contribute to the incidence of isolated cases of cleft lip/palate. This includes in particular sequence variants in the genes IRF6, PVRL1 and MSX1. The understanding of the genetic complexities involved in the morphogenesis of the midface, including molecular and cellular processes, has been greatly aided by research on animal models, including of the genes BMP4, SHH, SHOX2, FGF10 and MSX1.
Environmental influences may also cause, or interact with genetics to produce, orofacial clefting. An example of how environmental factors might be linked to genetics comes from research on mutations in the gene PHF8 that cause cleft lip/palate (see above). It was found that PHF8 encodes for a histone lysine demethylase, and is involved in epigenetic regulation. The catalytic activity of PHF8 depends on molecular oxygen, a fact considered important with respect to reports on increased incidence of cleft lip/palate in mice that have been exposed to hypoxia early during pregnancy. In humans, fetal cleft lip and other congenital abnormalities have also been linked to maternal hypoxia, as caused by e.g. maternal smoking, maternal alcohol abuse or some forms of maternal hypertension treatment. Other environmental factors that have been studied include: seasonal causes (such as pesticide exposure); maternal diet and vitamin intake; retinoids — which are members of the vitamin A family; anticonvulsant drugs; nitrate compounds; organic solvents; parental exposure to lead; alcohol; cigarette use; and a number of other psychoactive drugs (e.g. cocaine, crack cocaine, heroin).
Current research continues to investigate the extent to which folic acid can reduce the incidence of clefting.
Traditionally, the diagnosis is made at the time of birth by physical examination. Recent advances in prenatal diagnosis have allowed obstetricians to diagnose facial clefts in utero with ultrasonography.
Clefts can also affect other parts of the face, such as the eyes, ears, nose, cheeks, and forehead. In 1976, Paul Tessier described fifteen lines of cleft. Most of these craniofacial clefts are even rarer and are frequently described as Tessier clefts using the numerical locator devised by Tessier.
Cleft lip and clip palate is an "umbrella term" for a collection of orofacial clefts. It includes clefting of the upper lip, the maxillary alveolus (dental arch), and the hard or soft palate, in various combinations. Proposed anatomic combinations include:
Cleft lip and palate is very treatable; however, the kind of treatment depends on the type and severity of the cleft.
Most children with a form of clefting are monitored by a cleft palate team or craniofacial team through young adulthood. Care can be lifelong. Treatment procedures can vary between craniofacial teams. For example, some teams wait on jaw correction until the child is aged 10 to 12 (argument: growth is less influential as deciduous teeth are replaced by permanent teeth, thus saving the child from repeated corrective surgeries), while other teams correct the jaw earlier (argument: less speech therapy is needed than at a later age when speech therapy becomes harder). Within teams, treatment can differ between individual cases depending on the type and severity of the cleft.
Within the first 2–3 months after birth, surgery is performed to close the cleft lip. While surgery to repair a cleft lip can be performed soon after birth, often the preferred age is at approximately 10 weeks of age, following the "rule of 10s" coined by surgeons Wilhelmmesen and Musgrave in 1969 (the child is at least 10 weeks of age; weighs at least 10 pounds, and has at least 10g hemoglobin). If the cleft is bilateral and extensive, two surgeries may be required to close the cleft, one side first, and the second side a few weeks later. The most common procedure to repair a cleft lip is the Millard procedure pioneered by Ralph Millard. Millard performed the first procedure at a Mobile Army Surgical Hospital (MASH) unit in Korea.
Often an incomplete cleft lip requires the same surgery as complete cleft. This is done for two reasons. Firstly the group of muscles required to purse the lips run through the upper lip. In order to restore the complete group a full incision must be made. Secondly, to create a less obvious scar the surgeon tries to line up the scar with the natural lines in the upper lip (such as the edges of the philtrum) and tuck away stitches as far up the nose as possible. Incomplete cleft gives the surgeon more tissue to work with, creating a more supple and natural-looking upper lip.
In some cases of a severe bi-lateral complete cleft, the premaxillary segment will be protruded far outside the mouth.
Nasoalveolar molding prior to surgery can improve long-term nasal symmetry among patients with complete unilateral cleft lip–cleft palate patients compared to correction by surgery alone, according to a retrospective cohort study. In this study, significant improvements in nasal symmetry were observed in multiple areas including measurements of the projected length of the nasal ala (lateral surface of the external nose), position of the superoinferior alar groove, position of the mediolateral nasal dome, and nasal bridge deviation. "The nasal ala projection length demonstrated an average ratio of 93.0 percent in the surgery-alone group and 96.5 percent in the nasoalveolar molding group," this study concluded.
Often a cleft palate is temporarily covered by a palatal obturator (a prosthetic device made to fit the roof of the mouth covering the gap).
Cleft palate can also be corrected by surgery, usually performed between 6 and 12 months. Approximately 20–25% only require one palatal surgery to achieve a competent velopharyngeal valve capable of producing normal, non-hypernasal speech. However, combinations of surgical methods and repeated surgeries are often necessary as the child grows. One of the new innovations of cleft lip and cleft palate repair is the Latham appliance. The Latham is surgically inserted by use of pins during the child's 4th or 5th month. After it is in place, the doctor, or parents, turn a screw daily to bring the cleft together to assist with future lip or palate repair.
If the cleft extends into the maxillary alveolar ridge, the gap is usually corrected by filling the gap with bone tissue. The bone tissue can be acquired from the patients own chin, rib or hip.
Children with cleft palate are at risk for having velopharyngeal insufficiency (VPI). Velopharyngeal insufficiency refers to the inability of the soft palate to elevate and then close against the back wall of the throat during speech. This is usually because, despite the palate repair, the soft palate is too short to reach the back of the throat and close tightly against it. Velopharyngeal closure is necessary during speech because it closes off the nose from the mouth. This allows the air from the lungs and sound from the voice box to enter the mouth for normal speech. Velopharyngeal insufficiency can cause hypernasality (too much sound in the nasal cavity during speech) or audible nasal emission of the air stream. The lack of adequate airflow in the mouth can make the production of many speech sounds, (i.e., /p/, /b/, /t/, /d/, /s/, /z/, etc.) very difficult or impossible to produce.
Because of the lack of adequate airflow in the mouth for speech, children with cleft palate often compensate by producing speech sounds in the pharynx (throat area) where there is airflow. These speech errors improve intelligibility somewhat, but will require speech therapy for correction after surgical correction of VPI is done
Velopharyngeal insufficiency is a disorder of abnormal structure. Therefore, correction of VPI requires surgical intervention, or a prosthetic device in rare cases when surgery is not an option. Although speech therapy cannot correct VPI (including the hypernasality and/or audible nasal emission that occurs from VPI), therapy is often needed after VPI surgery to correct compensatory errors that develop as a result of VPI. Speech outcomes are usually better with surgical correction of VPI and necessary therapy in the preschool years.
Children with cleft palate are at increased risk for conductive hearing loss. This is caused by negative pressure and fluid buildup in the middle ear as a result of poor development of the tensor veli palatini muscle. This muscle is responsible for opening the eustachian tube to allow drainage of the middle ear. A tympanostomy tube is often inserted into the eardrum to aerate the middle ear. This is often beneficial for the hearing of the child.
Note that each individual patient's schedule is treated on a case-by-case basis and can vary per hospital. The table below shows a common sample treatment schedule. The colored squares indicate the average timeframe in which the indicated procedure occurs. In some cases this is usually one procedure (for example lip repair) in other cases this is an ongoing therapy (for example speech therapy).
|Repair cleft lip|
|Repair soft palate|
|Repair hard palate|
|Bone grafting jaw|
|Further cosmetic corrections (Including jawbone surgery)|
A craniofacial team is routinely used to treat this condition. The majority of hospitals still use craniofacial teams; yet others are making a shift towards dedicated cleft lip and palate programs. While craniofacial teams are widely knowledgeable about all aspects of craniofacial conditions, dedicated cleft lip and palate teams are able to dedicate many of their efforts to being on the cutting edge of new advances in cleft lip and palate care.
Many of the top pediatric hospitals are developing their own CLP clinics in order to provide patients with comprehensive multi-disciplinary care from birth through adolescence. Allowing an entire team to care for a child throughout their cleft lip and palate treatment (which is ongoing) allows for the best outcomes in every aspect of a child's care. While the individual approach can yield significant results, current trends indicate that team based care leads to better outcomes for CLP patients.
Outcomes assessment in CL/P has been laden with difficulty due to the complexity and longitudinal nature of cleft care (which spans birth through young adulthood). Pioneering efforts at outcomes comparisons between treatment protocols or between centers include the Eurocleft, CSAG, Americleft, and Scandcleft projects. One of the major limitations identified by these projects was the lack of data standards for outcomes assessment in cleft care.
Recently, the International Consortium for Health Outcome Measurement (ICHOM) proposed the Standard Set of Outcome Measures for Cleft Lip/Palate, which was developed in accordance with the guidelines of the WHO International Classification of Functioning, Disability, and Health (ICF). The ICHOM Standard Set includes measures for many of the important outcome domains in cleft care (hearing, breathing, eating/drinking, speech, oral health, appearance, psychosocial well-being, and team-based process metrics), and it includes clinician-reported, patient-reported, and family-reported outcome measures. The ICHOM Standard Set is considered open source (CC-BY-SA) and may be utilized freely by any cleft and craniofacial team or research group