OMFS - Cleft Lip and Palate

Question 1

What processes merge to form the upper lip, anterior maxillary alveolus, and nose?

Answer 1

Maxillary and nasal processes (medial, lateral) merge → upper lip and anterior maxillary alveolus

Maxillary and lateral nasal processes merge → ala of nose

Question 2

What processes merge to form the mouth?

Answer 2

Maxillary and mandibular processes merge → mouth

Question 3

How does CL develop?

Answer 3

Failure of fusion of medial nasal process and maxillary process

Question 4

At what time during gestation does CL/P occur?

Answer 4

Upper lip and premaxilla form at ~7 weeks

• Disruption here → CL and/or alveolus

Palatal shelves fuse at ~12 weeks

• Disruption here → CP (hard and/or soft palate)

Question 5

Why are L-sided secondary or palatal clefts more common than R-sided?

Answer 5

Up to 7th week gestation, the two palatal shelves lie almost vertically

As the neck straightens from its flexed position, the:

• Tongue drops posteriorly
• Shelves rotate superiorly to the horizontal position → fuse from ant to post to form palate by 12th week

It is believed that the R palatal shelf reaches the horizontal position first (L side susceptible to developmental interruption for longer period of time)

• This is true in rodents, and is thus assumed to be true in humans

Question 6

What structures form from the primary palate, and what structures form from the secondary palate?

Answer 6

Primary palate

• Lip
• Alveolar arch
• Palate anterior to incisive foramen (“premaxilla”)

Secondary palate

• Hard palate posterior to incisive foramen
• Soft palate

Question 7

Which orofacial muscles are anatomically abnormal in CL/P?

Answer 7

CL

• Orbicularis oris

CP

• Depends on whether partial or complete
• Complete cleft
• Veli palatinis (levator, tensor)
• Uvular
• Palatopharyngeus
• Palatoglossus

Question 8

What is Passavant’s Ridge?

Answer 8

• Observed during gagging and pronunciation of vowels
• Important mechanism in velopharyngeal closure (disruption → VPI)
• Transverse ridge or bulge produced by forceful contraction of superior pharyngeal constrictor on the posterior pharynx opposite of the arch of the atlas

Question 9

What is the blood supply to the palate (name the four main sources)?

Answer 9

1. Descending palatine artery → greater and lesser palatine branches
   
   • DPA = branch of maxillary artery
2. Ascending pharyngeal (2nd branch of ECA)
3. Ascending palatine (1st branch of facial artery)
4. Tonsillar branches (2nd branch of facial artery)

Question 10

What is the worldwide incidence of CL/P? What are the incidences of Asians, whites, and blacks?

Answer 10

1:700-800

Asians

• 1:500

Whites

• 1:1000

Blacks

• 1:2000

Question 11

Per the CDC, what’s the incidence of CL/P? What about just palate? What about just lip?

Answer 11

• Both lip + palate = 1:1600
• Just palate = 1:1700
• Just lip = 1:2800

Question 12

What percentage of CL/P patients are:

• U/l CL/P
• U/l CL
• B/l CL/P
• B/l CL

Answer 12

• U/l CL/P = 50%
• U/l CL = 25%
• B/l CL/P = 20%
• B/l CL = 5%

Question 13

What factors are known to cause cleft deformities?

Answer 13

< 40% of CL/P are of genetic origin

• Even fewer (< 20%) of isolated cleft palates are of genetic origin

Believed to be etiological factors:

• Viral infx
• Lack of certain vitamins
• Meds taken during the first 8 weeks of pregnancy
  
  • Corticosteroids
  • Diazepam (Valium)

Question 14

What’s the most common type of CL/P (eg, u/l or b/l, L or P or L+P)? What side do u/l presentations most commonly occur on? What sex is isolated CP more common in?

Answer 14

• U/l CL+P = most frequent combo
  
  • Boys > girls
  • Predominantly on the left
  • Hereditary incidence in these pts is fairly high
• Isolated CP = next most common
  
  • Girls > boys
  • Hereditary incidence in these pts is fairly low
• Bifid uvula incidence is ~2%, but usually asymptomatic
  
  • Although 20% have some degree of VPI

Question 15

What is the familial risk for developing CP?

Answer 15

Question 16

When can the face be imaged on prenatal ultrasound, and in what plane is the lip best visualized?

Answer 16

• Successful imaging of the face is usually not possible until 15 weeks gestation
• Lip is most easily visualized in coronal plane
• Identifying isolated CP may be more challenging, but is easiest to see in the axial plane

Question 17

What is the importance of auditory screening in the CL/P population?

Answer 17

• Recommended that all kids undergo a newborn hearing screen (recommended before 6 mo age)
  
  • If they do not pass, repeat the exam with audiologist and have f/u with ENT to check for middle ear effusions
• The same muscles that elevate the soft palate also tense and open the eustachian tube to equalize the middle ear
  
  • ie, kids born with clefts are at a higher risk for eustachian tube dysfunction and chronic middle ear effusions

Question 18

What are the currently available feeding aids for cleft pts?

Answer 18

• When bottle feeding cleft infants, important to remember they swallow more air when sucking than non-cleft pts (so it’s important to keep them upright at a 45° angle and burp them frequently
• Specific products
  
  • Mead Johnson = low-cost, compressible bottle that allows caregiver to squeeze milk into infant’s mouth as he or she is sucking
  • Pigeon Nipple = faster flow and can often be used by older infants on any bottle
    
    • The nipple itself is compressed against the hard palate and does not require sucking to dispel milk
  • Haberman feeder = more expensive and good for children who are small or premature
    
    • Has one-way valve that keeps milk in a soft chamber and nipple
    • Chamber can be pumped to dispel milk into infant’s mouth
    • Flow can be adjusted by rotating the nipple

Question 19

How can clefts be classified?

Answer 19

• Specific types of classification
  
  • Complete/incomplete
  • Prepalatal/palatal
    
    • U/l or b/l
      
      • Involving 1/3, 2/3, or all (complete)
  • Submucosal or bifid uvula
• Note - all palatal clefts can be described as 1/3, 2/3, or complete cleft of the soft or hard palate

Question 20

What is the difference b/w a complete and incomplete cleft of the lip?

Answer 20

• Complete = cleft of the entire lip and underlying premaxilla or alveolar arch
• Incomplete = involves only the lip

Question 21

What is a submucosal cleft and what are the difficulties it causes (and why)?

Answer 21

• Submucosal cleft = deficiency in the musculature of the palate due to failure of the levator muscle fibers to fuse completely in the midline
• Clinically, the palate looks intact because the overlying oral and nasal mucous membranes are present
• Usually leads to difficulties with speech and VPI because the muscles of the soft palate are unable to function normally
• Congenital absence of muscularis uvulae may also occur (w/ or w/o bifid uvula) and is often assx with palatal incompetence
• Characterized by:
• Bifid uvula
• Loss of posterior nasal spine
• Bluish midline streak on soft palate due to muscular diastases
• Notch may be present in the posterior hard palate

Question 22

What is a bifid uvula?

Answer 22

• Variation of cleft palate seen in 2% of normal US population
• May be assx with palatal incompetence
• Pts should be followed for possible speech problems

Question 23

What are the criteria for timing of CL repair?

Answer 23

• Sx repair of CL usually occurs b/w weeks 10-14 of age
• Traditionally based on rule of 10s
  
  • 10 weeks age
  • 10 Hb
  • 10 lbs

Question 24

What is Simonart’s band?

Answer 24

• Soft tissue band between margins of CL, nostril, or alveolar cleft when a complete skeletal cleft of the alveolus is also present
• Most of these soft tissue adhesions are located at the base of the nostril
• Often help maintain nasal form and decrease the dimensions of the soft tissue cleft and segmental displacement, possibly aiding in primary lip repair

Question 25

Who is a good candidate for a lip adhesion procedure, why is it used, and when is it usually performed? What are the pros/cons of it?

Answer 25

• Reserved for very wide clefts in which primary closure may not be possible
• Usually carried out at 3-4 mo age with definitive repair planned for 6-12 mo age

Pros/Cons

• Advantages include narrowing of a wide cleft and alignment of the alveolar arches
• Disadvantages = additional anesthetic and possibility of increased scar tissue formation

Question 26

What are the names of the four most common techniques for CL repair?

Answer 26

1. Lip adhesion procedure
2. Millard rotation advancement flap
3. Tennison Randall triangular flap
4. Delaire

Question 27

What is the Millard rotation advancement flap?

Answer 27

• Modified Z-plasty technique placed at the top of the cleft so that the point of greatest tension is placed at the base of the nares
• Most popular method of CL repair
• Used for complete, incomplete, and wide cleft repairs
• Ideal for closing incomplete or narrow clefts
• Technique
  
  • Downward rotation of the philtrum of the lip as a flap into normal symmetric position
  • Lateral lip segment advanced across the cleft and into the space behind the central lip
  • The final scar from the suture line closely recreates the philtrum of the lip on the cleft side

Question 28

What’s the timing for CP repair?

Answer 28

• In most centers, CP repair is done in first 10-18 mo of age
  
  • This is the age at which speech skills are beginning to develop
• Some centers delay as long as 18-24 mo (after eruption of M1s)
• Difference in timing is mostly based on differing opinions regarding balance of needs for normal speech vs normal palate growth and occlusion

Question 29

What are the four main goals of CP repairs?

Answer 29

1. Separate the nasal and oral cavities through closure of both mucosal surfaces
2. Construction of a water-tight velopharyngeal valve
3. Preservation of facial growth
4. Good development of aesthetic definition and functional occlusion

Question 30

What are the names of the four main techniques for CP repair?

Answer 30

1. von Langenbeck
2. Furlow palatoplasty
3. V-Y pushback
4. Wardhill-Kilner

Question 31

What is the von Langenbeck operation?

Answer 31

• Long, relaxing incisions laterally, with elevation of large mucoperiosteal flaps from the hard palate
  
  • This is then bipedicled anteriorly and posteriorly
• Cleft margins of both the hard and soft palates are approximated at the midline
• Levator muscles are completely detached from their abnormal bony insertion and soft palate musculature is repaired in the midline
• Palatal lengthening procedure no included

Question 32

What is a vomer flap?

Answer 32

• Elevation of a wide, superiorly based flap of nasal mucosa from the vomer to close the hard palate
• In b/l clefts, vomer flaps can be obtained from each side of the vomer
• Avoids the need for elevating large mucoperiosteal flaps from the hard palate
• Also avoids the potential risk of resultant maxillary growth disturbances

Question 33

What are the two most common postop complications of CP?

Answer 33

1. Hypernasalic speech = most common (up to 30%)
2. Oronasal fistulas (ON fistula) = second most common (10-21%)

• Typically at either end of the hard palate (ie, at the anterior alveolus of at the junction of the soft and hard palate)

Question 34

What are the major sequelae of an unrepaired CP?

Answer 34

• Numerous, and they begin at birth and continue for pt’s lifetime

1. Inability to build up suction
2. Nasal regurgitation
3. Recurrent otitis media (poor eustachian tube function → may lead to fluid in middle ear → recurrent otitis media)
4. Breathing problems, especially if short chin and tongue falls posteriorly → inspiratory obstruction
   
   • Pierre Robin sequence
5. Speech problems
   
   • Hypernasality with vowel sounds
   • Distortion of pressure consonants
6. Adjacent teeth angled into cleft and possibly malformed or absent (if alveolar ridge involved)
7. Dental caries and severe malocclusion

Question 35

What is VPI?

Answer 35

• VPI = velopharyngeal insufficiency
• During speech production, velum is elevated and pharyngeal wall moves to close the nasopharynx off from oropharynx to produce oral speech sounds
  
  • When this is deficient, leads to:
    
    • Hypernasality
    • Nasal remissions
    • Compensatory mechanisms
• Broad term used to describe any of these:
  
  • Resonance disorders due to structural abnormalities
  • Neurologic disorders resulting in velopharyngeal incompetence
  • Functional issues leading to velopharyngeal mislearning

Question 36

How is VPI diagnosed?

Answer 36

• No single technique
• Usually based on combo of
  
  • Perceptual assessments by speech language pathologist
  • Visualization of the mechanism during function via techniques like nasopharyngoscopy and videofluoroscopy
  • Data collected from indirect techniques like nasometry
• Includes formal speech-language evaluation

Question 37

What muscles are the most important in VP closure?

Answer 37

• Levator veli palatini muscles (pull the middle 1/3 of the soft palate superiorly and posteriorly to produce firm contact with posterior pharyngeal wall at about the level of the adenoidal pad)
• Other muscles that contribute
  
  • Palatopharyngeus muscles (pull soft palate posteriorly)
  • Muscularis uvulae (cause uvula to thicken centrally with contraction)
  • Superior pharyngeal constrictors (move the lateral pharyngeal walls medially or posterior pharyngeal wall anteriorly)

Question 38

How is VPI managed, and at what age does this begin?

Answer 38

• Speech therapy with parental counseling starting age 6 mo
• Individual child therapy should begin at age 4 y (or when definitive dx made)
• Dental prosthesis may also be helpful
• About 20-25% need sx
• Techniques
  
  • Secondary palatal lengthening
  • Pharyngeal augmentation using soft tissue or implants
  • Pharyngeal flaps (convert incompetent nasopharynx into two lateral ports and are most successful in pts with good lateral pharyngeal wall motion)

Question 39

What are the goals of ACBG?

Answer 39

1. Closure of ON fistulas
2. Give continuity to maxillary arch
3. Provide support to ala on cleft side by recreating piriform rim
4. Provide bone for eruption of permanent teeth
5. Facilitate orthodontic movement of teeth
6. Improve lip support
7. Create patent nasal airway

Question 40

What is the ideal age for alveolar cleft repair?

Answer 40

• Traditionally, grafts placed between ages 9-11
  
  • Early grafting at age 5-7 is becoming more popular
• Most studies suggest graft should be placed before eruption of the permanent canine and when canine root is 1/4 to 1/2 (or 1/2 to 2/3) developed
• Root resorption and graft failure are common when bone grafts are placed after eruption of the canine
• Ortho tx to stimulate growth and tooth eruption should be instituted w/in 3 mo before graft
• Ortho expansion of maxillary arch after grafting instead of before (approx age 7-12) has also been advocated

Question 41

When should the cleft site be orthodontically expanded prior to grafting?

Answer 41

• Maxillary segments should be expanded prior to grafting to correct posterior and/or anterior crossbites
• Care should be taken to avoid ortho movement or rotation of teeth near the cleft site that may have questionable bony support

Question 42

Which is the ideal bone for alveolar cleft repair?

Answer 42

• Particulate bone with cancellous marrow = best choice
• Due to these properties, which are the most predictable in this type of bone:
  
  • Osteoinduction (inducing bone formation)
  • Osteoconduction (serving as a scaffold)

Question 43

What are the most common skeletal jaw deformities in CP pt?

Answer 43

Vary, but generally include one or more of these:

1. Midface deficiency
2. Maxillary transverse deficiency
3. Class III skeletal and occlusal deformity
4. Prognathic mandible

Question 44

What is the ideal age for cleft orthognathic sx?

Answer 44

• Similar to that of children w/o CL/P (ie, ideally upon completion of facial growth)
  
  • Girls age 14-16
  • Boys age 16-18
• Can be done earlier for these reasons, but must recognize that there may be additional sx required due to relapse:
  
  • Psychosocial considerations
  • Improvement of OSA
  • Children with large AP deficiencies

Question 45

What incision modifications should be considered during cleft orthognathic sx in u/l CL/P and b/l CL/P pts?

Answer 45

• In u/l CL/P:
  
  • Typical Le Fort I with circumvestibular incision
• In b/l CL/P
  
  • Leave mucosa intact from canine to canine to maintain blood supply to maxilla
    
    • Incisions made from distal of canine to mesial of PM1 and subperiosteal dissection and osteotomies are completed through these windows
  • To use nasal-septal osteotome, small stab incision made at midline at height of vestibule and osteotome is inserted

Question 46

What are generally safe guidelines for maxillary advancement distance vs distraction osteogenesis?

Answer 46

• Le Fort I can usually be accomplished in pts with CP requiring ≤ 6 mm of advancement (up to 10 mm in some cases)
• Must consider the number of previous palatal sxs and the amount of scarring present
• Advancement of > 6-10 mm is usually best treated with distraction osteogenesis

Question 47

Most common complications specific to cleft orthognathic sx?

Answer 47

• Risk of developing VPI → hypernasalic speech
  
  • In most cases, this resolves w/o intervention in 6-12 mo (speech often returns to preop quality)
  • If after 12 mo it has not resolved, pts may require pharyngeal flap to improve quality of speech

Question 48

What are the common features of u/l cleft nasal deformities?

Answer 48

• All deformities are on the cleft side (eg, nasal septum convex on cleft side, deviated toward cleft side) with the exception of the nasal tip being deviated toward the non-cleft side and the columella maybe being deviated toward the non-cleft side
• Nasal septum
  
  • Convex
  • Deviated
• Nasal tip
  
  • Deviated toward non-cleft side
  • Depressed dome (poor tip support)
• Lower lateral cartilage
  
  • Weaker, smaller, or misshapen
  • Angle between medial and lateral crura excessively obtuse
• Pyriform aperture
  
  • Webbing of soft tissue
• Nostril
  
  • Horizontally-oriented
  • May be asymmetric
• Columella
  
  • May be shorter
  • May be deviated toward non-cleft side
• Nasolabial fistula may be present
• Hypertrophy of turbinate
• Poor support of ala (due to clefting alveolus, if present)

Question 49

What are the four common features of b/l cleft nasal deformities?

Answer 49

1. Broad and bifid nasal tip
2. Displacement of alar cartilages inferiorly with hooding of the nostril
3. Wide horizontal nostrils
4. May have shortening of columella

Question 50

What is the timing of cleft rhinoplasty?

Answer 50

• Some of the cleft nasal deformities are addressed at time of primary lip repair
  
  • Correction of flared ala
  • Correction of nasal-septal deviation
  • Improvement of nostril symmetry
• Some surgeons advocate correction of tip deformities with various techniques at the time of lip repair, but this is controversial due to the possibility of adverse effects on nasal growth
• Formal, open or closed rhinoplasty is usually reserved for the:
  
  • Completion of facial growth
  • Consolidation of maxillary arch
  • Correction of maxillary hypoplasia

Question 51

What is the traditional sequence for CL/P repair?

Answer 51

• At birth = CL/P team evals child
• 10 weeks = CL repaired
• 1 year/12 mo = child re-evaluated by CL/P team
• 12-18 mo = CP repaired (soft + hard)
• 5-7 y = pharyngeal flap (if necessary)
• 5-8 y = interceptive ortho
• 7-8 y = maxillary expansion (if necessary)
• 9-11 y = alveolar cleft grafting
• 12-13 y = comprehensive ortho initiated
• 14-16 y = orthog sx and nasal sx done (if necessary)