Maxfacts

Classification

Numerous classifications exist but the most useful is to describe the actual deformity in words and these deformities have matching Read and ICD (International Classification of Diseases) codes. These include:

• cleft lip and palate – unspecified Read code P9, ICD code 749
• cleft lip – Read code P91, ICD code 749.1
• cleft palate – Read code P90, ICD code 749.0
• cleft lip and palate – Read code P92, ICD code 749.2
• unilateral complete cleft lip and palate – Read code P921, ICD code 749.21
• bilateral complete cleft lip and palate – Read code P923, ICD code 749.23.

The advantage in describing the actual deformity is that it links both the prognosis and treatment for the cleft. One of the disadvantages, however, is that the description may not be entirely accurate: cleft palate can mean anything from a cleft uvula through a cleft soft palate to cleft of the soft and hard palate. A small cleft of the soft palate is a relatively simple surgical problem with an extremely good long-term prognosis in most instances, whereas a wide complete cleft of the palate may be both difficult to close, particularly in the hard palate / soft palate junction, and can result in significant speech impediment and long-term growth disturbance due to scarring.

Prevalence

Clefts of the lip and palate are the most common craniofacial malformations, and comprise 65 % of all anomalies affecting the head and neck. There are two useful distinct types of cleft anomaly, cleft lip with or without cleft palate, and isolated cleft palate. There is a difference in the pathogenesis (see below) of the two.

Cleft lip and palate

Amongst white people there is an incidence of approximately 1 : 750 live births, with an increase in prevalence. In Germany it is well accepted that there is an incidence of 1 : 500. The figure 1 : 1000 has been used in international terms as incidence varies between races and nationalities. The difficulty of accurate data collection in international terms has been discussed at length in specialist texts.

Family history can be found in around 40 % of cases although the actual genetics of cleft lip and palate are extremely complex. The commonly quoted statistic is that the risk for unaffected parents having a second child with the anomaly is around 1 : 20. Clefts of lip and palate are commoner in males than females and more often affect the left side. The cleft is often more severe if it arises in the less common variant, that is in a female on the right. It should be noted that the prevalent statistics for cleft lip and palate vary widely both geographically and between different racial groups (orientals approximately 1 : 425 live births, afro-caribbeans approximately 1 : 3000 live births).

Isolated cleft palate

This cleft occurs in around 1 : 2000 live births and is commoner in females than males. A genetic history is less clear in these, there is said to be a family history in approximately 20 % of cases, and the risk to further offspring is around 1 : 80. Isolated cleft palate is often found in other syndromes such as Down syndrome, craniofacial syndromes such as Treacher-Collins syndrome and Pierre Robin syndrome, and bone disorders such as Klippel-Feil syndrome.

Aetiology

The aetiology of cleft is multi-factorial. The mechanics of clefting are thought to be a failure of fusion of the embryological processes that comprise the upper lip at the sixth week of intrauterine life.

The hard and soft palates are formed by a different mechanism. The process described is a ‘flip up’ of the palatal shelf from a vertical to a horizontal position, followed by fusion to form the secondary palate around the eighth week in utero. This requires these embryological processes both to move into position by the process of ‘flip up’ and to grow until they come into contact. Failure of growth, the ‘flip up’ process or breakdown of the overlying epithelium to allow the flow of mesenchyme (early, foetal undifferentiated cells that develop into connective tissues) to create a solid structure can all result in clefting of the palate.

One of the suggestions to explain why isolated cleft palate is more common in females than males is because the process of transposition of the palatal shelves occurs later in the female foetus, therefore a greater opportunity exists for environmental insult to affect successful ‘flip up’.

Submucous clefts have been reported to be the most common form of cleft in the posterior palate – 1 : 1200 normal children. Common abnormalities include hyper-nasality, chronic otitis media, nasal regurgitation. The signs that may be indicative of a submucous cleft include: bifid uvula, translucent palatal raphe area, palpable notch in the midline of the posterior hard palate and triangular muscle ridging on palatal elevation. The most common reason for treating a person with a submucous cleft palate is because of abnormal, nasal-sounding speech.

Issues in the management of cleft lip and palate

Approximately 20 % of babies with clefts, particularly those with isolated cleft palates, will have associated congenital abnormalities often of the heart or extremities.

Failure of growth and the pre-existing cleft lead to clear aesthetic issues. The growth problems have also in the past been made remarkably worse by post-surgical scarring and distortion. Concerns highlighted by the Eurocleft Study around multiple interventions in cleft children in a disjointed and discordant fashion coupled with observations on the adequate growth patterns in individuals with unoperated clefts, raised concerns that in some instances post-surgical distortion due to scarring and inappropriately timed or performed surgery created defects to rival the clefts themselves.

In the UK this problem has been addressed by a national recommendation that the treatment of cleft lip and palate should be centralised to centres which could be adequately audited and consisted of a team, cleft surgeon, orthodontist, speech and language therapist, otorhinolaryngologist, specialised nursing, clinical genetics advice, paediatric intensive care facilities and the opportunity for neo-natal counselling and specialist health visitors. Adequate access to paediatric dentistry and restorative dentistry were essential as was access to appropriate psychological support. Within the UK there has been a very gradual move towards co-ordinated teams such as these managing all cleft patients in a region, creating the opportunity for high volume auditable outcomes. The opportunities for development of individual expertise and training become self-evident as does the restriction of practice to a very limited number of people with the inherent potential problems this could create.

In Germany there are no regulations concerning treatment of cleft lip and palate. It is the patient (parent) who has to make the decision where the child is to be treated. Of course, there are chatrooms, brochures and a lot of information, especially via the internet. Usually these patients are treated at university hospitals or at least hospitals with major oral & maxillofacial surgery units. There is competition between the hospitals to treat these patients. Competition is felt to be one precondition for good results. Given the ‘centralisation’ concept now solidified into the UK NHS system was based on the results of the Eurocleft Study, it is fascinating to see how the major European country has responded.

In the USA, while degrees of specialisation are widely accepted, it would be hard to imagine the state dictating to parents or patients where and how they or their child should be treated. There are few areas of elective surgical practice that have been subjected to what is clearly a political differentiation rather than one based on objective outcome criteria. One can see, at least in this instance, the common Northern American criticism of the UK NHS as ‘socialised medicine’. What will be genuinely fascinating will be the long-term outcomes produced by such a process compared to similar centralised systems for example in China, compared to outcomes from Germany and the USA - objectively and independently assessed.

Lip repair

In general, neo-natal lip repair, that is very early lip repair has fallen into disrepute, most surgeons will undertake lip repair between three and six months old. The classical rule was the rule of 10 which is still referred to (the child is 10 weeks old, 10 kg in weight, and has a haemoglobin above 10 g/dl). Even allowing for generalisation this seems to suggest rather obese babies. In Germany the rule is that operation is not before 3 months of age and not under 5 kg in weight. Usually at the age of 3 months the babies have 7 or 8 kg of maximum weight.

Palate repair

Closure of the palate in the UK is generally relatively early; the principle here is to attempt to close the palate before the development of speech and a hyper-nasal speech pattern. In some European countries closure of the hard palate is delayed in order to minimise the unwanted effects of early surgery upon growth. This may improve transverse growth of the maxilla but there is an obvious compromise in terms of speech development. In Germany there are also a lot of different concepts concerning sequence and timing of the operation. The common opinion is that the palate should be closed latest at the age of 2 years.