Describe the embryology of the head and neck
Wk 4-5: 6 paired branchial arches (paired swellings) form along the neck of the embryo
1st arch = craniofacial clefts, 2nd arch = tonsilar fossa
Outside grooves = clefts (between arches 1&2 = external auditory meatus and eardrum)
Inside grooves = pouches (out pouchings of foregut)
Stomadeum = cranial opening of foregut → mouth and nose
Skeletal components = from inward migration of neural crest cells
What is present in the 1st branchial arch?
What syndromes are associated in this area?
Paired maxillary prominences → Quadrate cartilage → incus + greater wing sphenoid Bones → maxilla, zygoma, squamous temporal bone (intramembranous ossification)
Paired mandibular prominences → Meckel’s cartilage → malleus + mandibular condyles
Artery → maxillary branch of external carotid
Nerve - Trigeminal → muscles of mastication (temporalis, masseter, pterygoids, ant belly digastric, mylohyoid, tensor veli palatine, tensor tympani. Motor from mandibular branch, sensory from all three divisions of V.
Mesenchyme → dermis of the face, direct ossification → Body and ramus of mandible
Syndromes → Treacher Collins, Pierre Robin, Stickler.
What is present in the 2nd branchial arch?
What syndromes are associated in this area?
Artery → Stapedial
Cartilage → Forms stapes, lesser horn and upper part hyoid
Bon e→ body and ramus of mandible
Nerve → Facial VII
Muscles → Stapedius, Stylohyoid ,Muscles of facial expression, Post belly digastric
Syndromes → Möbius’ syndrome = failure of innervation of facial muscles
What is present in the 3rd pharyngeal pouch?
What syndrome is associated with this area?
Cartilage → greater horn and inferior body of hyoid
Nerve → IX Glossopharyngeal
Muscles → stylopharyngeus, upper pharyngeal constrictors
Thymus and inferior III parathyroids
Syndromes - Velo-cardio-facial (=DiGeorge)
What develops from the 4th & 6th arches?
Cartilage - Thyroid, cricoid, arytenoid, corniculate and cuneiform
Nerve → superior laryngeal branch of Vagus
Muscles → cricothyroid, levator palati, palatopharyngeus, palatoglossus (remaining palate muscles) and lower constrictors of pharynx.
6th arch intrinsics supplied by recurrent laryngeal branch of Vagus
Superior VI parathyroids
Describe the embyology of facial development
Wk 4-6
Frontonasal prominence, 2 maxillary and 2 mandibular prominences
Frontonasal prominence is formed by proliferation of mesoderm ventral to forebrain (NOT from branchial arches)
4th wk
The developing frontonasal prominence, paired maxillary processes and paired mandibular processes surround the primitive oral cavity
5th wk paired placodes (ectodermal thickenings) form on inferior border of frontonasal prominence Medial placode → medial nasal process Lateral placode → lateral nasal process Between the two = nasal pit → nostril
6th wk
Medial nasal processes have merged with maxillary processes → upper lip and primary palate
Lateral nasal processes → nasal alae
Mandibular processes fuse → lower jaw
How do the different congenital abnormalities form as a result of failed fusion?
Failure of fusion of
How does the palate form?
6th wk
How does the neural crest form and what does it form?
What is cleft lip and palate?
Cleft Lip → congenital abnormality of the primary palate (fuses first).
Anterior to the incisive foramen = lip, alveolus, hard palate ant to foramen.
Can be complete / incomplete / microform, uni / bilateral, +/- cleft palate
Complete = separation of lip, nasal sill + alveolus
Incomplete = variable lip shortness, nasal sill intact - Simonart’s band
Microform (‘form fruste’) - vertical furrow or scar, notch in vermillion and white roll, variable lip shortness
Cleft Palate → congenital abnormality of the secondary palate (fuses second).
Posterior to the incisive foramen = remaining hard palate lying posterior to foramen and soft palate.
Can be uni / bilateral, submucous
What is the incidence of CL&P?
CL / CLP UK → 1 in 700 Caucasians → 1 in 1000 live births Asians → 2 in 1000 Africa → 0.4 in 1000
Combined CL&P → 45% Isolated CP → 30% Isolated CL → 20% Left : Right : Bilateral CL = 6 : 3 : 1 CL/P - more common in boys CPO - more common in girls
250,000 per year worldwide, 10% get repaired
1000 per year in UK
CSAG - Clinical Standards Advisory Group
1998 - CL&P report showed that cleft care outcomes in UK were poor compared to N Europe.
Recommendations: 57 cleft units amalgamated to 8 -15 regional centres doing >30 cases / yr.
The aim of this reorganisation was to concentrate surgical and other specialist skills and to facilitate audit and research.
What is the aetiology of CL and CLP?
CL and CL&P ♂ > ♀ 2 : 1 Relative family assoc If ..... , chance of CL = - no clefts 0.1% - 1 sibling 4% - 2 sibs 10% - parent 4% - sib + parent 17% Chromosome 6P, TGFa, TGFb implicated Not usually associated with syndromes except - Van der Woude (AD – Chromosome 1) Multiple lip pits, Absent second premolars. Popliteal pterygia (webbing) Drugs – Retinoids, anticonvulsants, steroids, folate antagonists, smoking
What is the aetiology of CP?
Isolated CP 1:2000 live births ♀ > ♂ 2:1 non-syndromic CPO If ...... , chance of CP = - 1 sibling 3.5% - 2 sibs 13% - 1 parent 3.5% - 1 parent + sib 10% - 1 parent + 2 sibs 24% - up to 60% are part of syndrome rather than familial
How does CL occur?
CL caused by either
How do you classify cleft lip and palate?
Kernohan’s Strip Y classification
Others
Veau classification 4 = SP, +HP, + uni / bilateral prepalate
LAHSAL - lip, alveolus, HP, SP, alveolus, lip (capital letter = complete)
What is the anatomy of a complete cleft lip?
What is the anatomy of an incomplete cleft lip?
Simonart’s Band: A bridge of skin that crosses the bottom of the nostril on the cleft side of a cleft lip - giving the appearance of an intact nasal sill
Forme fruste / microform cleft = mild form of incomplete CL
- Kink in alar cartilage, notch in vermillion, fibrous band across the lip, muscles in wrong place.
Prenatal screening of CLP (Matthews PRS 1998)
What occurs at the initial assessment of a cleft lip baby?
How do you counsel parents of newly diagnosed CLP?
Congratulate parents on new baby.
Introduce yourself and explain why you’re there:
(a) Take a history, examine (baby’s cleft, general health + breathing and feeding) and highlight concerns and advise.
(b) Counsel and educate parents on MDT, imminent assessments and surgery.
- hearing
- 3mths CL and ant palate repair
- 6-9mths post palate repair
(c) Outline the follow-up with different teams and possible future surgery. OPD: - hearing - SLT - dental & orthognathic - psychology
Future surgery + times
(d) Provide point of contact for parents via cleft nurse.
Tell me about how to counsel mum about feeding CLP babies
difficulty in sucking effectively as unable to create a good vacuum inside the mouth, and correctly position the tongue.
cleft palate only babies may be more difficult to feed than those with cleft lip or cleft lip and palate.
Occasionally, may need naso gastric tube feeding and teat/breast feeding.
Obturator plates
Can try breast feeding Feed at 45 degrees, 20-30mins (longer will tire baby out) The bottle (or in the case of the Haberman feeder, the teat) can be squeezed while the baby is sucking. The teat often has a one-way valve which keeps it full of milk. This is helpful for babies who can compress the teat but can't generate suction. It is also thought to minimise wind. 'Pigeon nipple' - teat has 'cross-cut' rather than a hole in the end. This stops milk dripping into the baby's mouth when they have stopped for a rest during feeding.
Haberman feeder (special needs feeder) - teat is squeezed Orthodontic shaped teat (MAM) Hole on non-cleft side and towards the tongue so milk is aimed downwards and away from the cleft. If insufficient energy to suck from a teat, use cup and spoon method - scoop attached to a soft bottle (e.g a Softplas bottle and scoop)
What is presurgical orthopaedics?
It can be divided into dynamic or static appliances
50% units in UK and 75% units in US use it
Static
Dynamic
- Latham device
How do you explain to parents the course of treatment for CLP?
Explain MDT and discuss course of treatment
Birth
- Hospital visit to family by one of the clinical nurse specialists
Outpatient MDT clinic - discuss operation
6-8 weeks - hearing test +/- paediatric OPA
3 months - Admission for lip repair
6-9 months - Admission for palate repair
12 months - MDT clinic - post op and hearing test
18 months - SLT assessment
2 years - MDT - cleft clinic
3 years clinic - SLT assessment
4 years MDT - cleft clinic
5 years OPA - clinical review
7.5 years MDT - cleft clinic
10 years Outpatient clinic - clinical review
12.5 years MDT - cleft clinic
15 years Outpatient clinic - clinical review
16 years MDT - cleft clinic
20 years Outpatient clinic - clinical review
What is the surgical timeline?
3/12: lip & anterior hard palate
lip - Millard rotation advancement
ant hard palate - vomerine flap
nose - McComb
6/12: remaining hard & soft palate
intravelar veloplasty, vomerine flap
Age 3-5:
lip (lengthening) & nose revision (Tajima)
palate or throat (pharyngoplasty - superior pharyngeal flaps or Hynes, Orticochea) surgeries
speech therapy
Age 6: orthodontics (early dental rx)
Age 7-10: closing of gum line with bone grafting from hip (alveolar bone grafting) to prevent root of canines collapsing into cleft
Age 11: orthodontics (permanent dentition)
Age 12-18yrs: jaw surgeries, further lip and nose revisions (orthognathic e.g. Le Fort 1 advancement to correct Class III malocclusion, rhinoplasty)
Why not lip & palate at 3/12?
o babies are obligate nasal breathers up to 6/12 and nasal secretions in babies are moist.
o Also no evidence that repair <1yr → speech