Cleft lip and/or palate (CLP) is a relatively common, non-life-threatening abnormality. Its aetiology is complex: it can occur in isolation but may be associated with a chromosomal or teratogenic syndrome – an associated syndrome is thought to exist in around 30% of all patients with CLP. The most common forms of CLP involve disruption of the tissue planes above the lip extending to nostrils and palate (hard and soft palate may be involved). Most only involve the upper lip and/or palate. Very rarely other parts of the face may be affected.
Although not a major cause of mortality, it can lead to poor feeding, failure to thrive and impaired survival in places where corrective surgery is not available. Children may experience social stigmatisation, in addition to problems with speaking and hearing
The defects in CLP arise very early in embryonic development, with genetic and environmental factors playing a part.
- An epidemiological study in 2012 suggested a worldwide incidence of around 0.8/1,000 live births.
- CLP is more common in Asian populations
- Cleft lip (with or without cleft palate) is more frequent in males while Cleft palate alone is more common in females.
- Cleft lip alone may have stronger genetic associations than cleft palate (with or without cleft lip).
These are thought to be a mixture of genetic and environmental/teratogenic factors in non-syndromic CLP. Pre-pregnancy planning is known to exert a protective effect
There may be varying levels of genetic predisposition, which environmental factors then influence.
- If both parents are unaffected, but have one child with a cleft, the chance of the second child being similarly affected is 2-8%.
- If one or other parent has a cleft, the risk of a cleft in a child is 4-6% with each pregnancy.
- There is a known risk in taking certain types of drugs during pregnancy – eg, phenytoin, isotretinoin, sodium valproate, benzodiazepines and corticosteroids.
- Maternal smoking, both in the first trimester and periconceptually is associated with increased risk.
- There is debate on the role of folic acid: nutritional factors such as folate deficiency have been suggested as a risk but studies of the effects of vitamin supplementation remain controversial and there is some evidence for the importance of deficiency in other nutrients such as zinc and cholesterol.
- The lip has usually formed by 5-6 weeks of intrauterine life.
- The palate has formed by 10 weeks.
- The cleft may be picked up by high-resolution ultrasound at 20 weeks of gestation.
- Diagnosis is otherwise made after delivery.
Cleft lip alone
If the cleft affects the lip only and does not affect the palate is is known as cleft lip.
- Cleft lip presents with an obvious gap in the newborn lip – usually the upper lip is affected.
- There may be a small gap in the lip (complete cleft) with the split running from the philtrum to the nostril.
- There may just be an indentation (partial or incomplete cleft).
- Cleft lip may be unilateral or bilateral.
Cleft palate (with or without cleft lip)
- Cleft palate condition occurs when the two plates in the base of the skull which form the hard palate fail to fuse.
- The cleft is therefore central in the palate, and the soft palate is usually cleft as well.
- Most commonly, cleft lip is also present.
The newborn may have difficulty bottle-feeding as a consequence of being unable to create a sufficient vacuum. However, most babies are able to be breast-fed.
- Special teats and bottles are available to deliver the milk to the back of the throat. A further option is to use a dental plate to seal the roof of the mouth.
- There may be associated poor weight gain but where the defect is corrected, children usually catch up by age 6 months.
Ideally, patients should be managed by a multidisciplinary team which includes:
surgeons, ENT speacialits, speech therapists and dentists.
This comprises the bulk of the treatment. A number of operations will be required as the child grows.
Primary lip closure is performed at three months after birth, as long as weight and haemoglobin levels are adequate.
- Palate closure is performed at 6-12 months.
- Further operations are performed to improve appearance.
- Chronic glue ear.
- Hearing loss; the muscles of the palate affect the ear.
- Dental cavities.
- Displaced teeth.
- Poor speech; the degree of problem is not related to the size of the defect. Speech is normally fine after repair, but may sound nasal.
- Lip deformity.
- Nasal deformity.
- Poor feeding, failure to thrive.
- Social exclusion.
- Psychological distress.
Treatment takes place over several years as the child grows and the palate and dentition develop. However, it is possible to achieve a normal appearance, and normal speech and eating habits, early in the process.