Orofacial Clefts Course Information Course Sponsor Innovative Educational Services Provider Approval



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Orofacial Clefts

Orofacial Clefts
Course Information
Course Sponsor - Innovative Educational Services
Provider Approval - ASHA Approved Provider of Continuing Education. Provider Code: AAVE
Course Description

“Orofacial Clefts” is an asynchronous web-based continuing education program that presents current information concerning congenital orofacial clefts including epidemiology, embryology, etiology, classification, associated syndromes, diagnosis, and interdisciplinary care.


Course Rationale

The purpose of this course is to present contemporary information regarding orofacial clefts to speech-language and audiology professionals so that they may have an improved understanding of the condition and provide optimal care to individuals affected by this disorder.


Learner Outcomes

At the end of this course, the participants will be able to:



  1. define the epidemiological occurrence and societal impact of orofacial clefts

  2. identify the embryological sequence that results in orofacial clefts

  3. Identify etiology and risk factors for orofacial clefts

  4. describe orofacial clefts utilizing accepted classification systems

  5. identify syndromes that have associated orofacial clefts

  6. recognize current mechanisms used to diagnosis orofacial clefts

  7. list and define the roles of cleft palate and craniofacial teams

  8. define the standards of care and treatment goals for individuals with orofacial clefts

  9. identify common feeding issues associated with orofacial clefts

  10. differentiate between the various surgical techniques used to repair orofacial clefts

  11. recognize the psychosocial issues experienced by individuals with an orofacial cleft

  12. identify audiology issues and interventions associated with orofacial clefts

  13. identify speech-language issues and interventions associated with orofacial clefts

  14. identify dental issues and interventions associated with orofacial clefts


Course Instructor - Michael Niss DPT, President, Innovative Educational Services
Instructor Conflict of Interest Disclosure – Dr. Niss receives compensation as an employee of Innovative Educational Services
Course Instructor - Niva Kilman MS, CCC-SLP, ASHA CE Administrator, Innovative Educational Services
Instructor Conflict of Interest Disclosure – Ms. Kilman receives compensation as an employee of Innovative Educational Services
Methods of Instruction – Asynchronous text-based online course
Target Audience – Speech-Language Pathologists, SLP Assts, Audiologists, Audiology Assts
Course Educational Level - This course is applicable for introductory learners.
Course Prerequisites - None
Criteria for Issuance of Continuing Education Credits - score of 70% or greater on the written post-test

Continuing Education Credits - Three (3) hours of continuing education credit
Course Price - $29.95
Refund Policy – 100% unrestricted refund upon request

This program is offered for .3 CEUs (introductory level; professional area).
Orofacial Clefts
Course Outline
page

Course Information 1 Begin hour 1

Course Outline 2

Overview Orofacial Clefts 3

Epidemiology 3

Embryology 3-4



Etiology 5-7

Classification 7-10

Tessier Classification 7-8

Van der Meulen Classification 8-9

LAHSAL Classification 9-10

Syndromes with Associated Orofacial Clefts 10-14



Van der Woude Syndrome 11

Pierre Robin Sequence 11-12



Treacher Collins Syndrome 12

Apert Syndrome 12-13

Crouzon Syndrome 13

Stickler Syndrome 13-14 End hour 1

Diagnosis 14 Begin hour 2

The Health Care Team 14-16

Cleft Palate Team 15

Craniofacial Team 15-16

Standards of Care 16-19

ACPA Parameters of Care 16-17

Standards for Team Approval 17-19

Treatment Goals 19-20

Nursing and Feeding 20-22

Feeding Issues 20

Bottle Feeding 20-21

Breast Feeding 21-22

Nasoalveolar Molding (NAM) 22


Surgical Interventions 22

Schweckendiek’s Technique 22-23

Von Langenbeck Palatoplasty 23-24

Modified Von Langenbeck Palatoplasty 24

The Furlow Z-plasty 24-25

Palatal Lengthening – V-Y Pushback 25


Alveolar Bone Grafting 25-26

Orthognathic (Jaw) Surgery 26-27 End hour 2



Psychosocial Issues 27-28 Begin hour 3

Otolaryngology and Audiology 28-29


Speech and Language 29-34


Communication Disorders 29-31

Abnormal Nasal Resonance 31

Velopharyngeal Insufficiency (VPI) 32-33

Speech Therapy 33

Timeline for Speech Therapy Intervention 34

Dental and Orthodontic Care 35-36

The Deciduous Dentition Period 35

Mixed Dentition Period 35-36

The Permanent Dentition Period 36

Timeline for All Health Care Interventions 36-37

Resources 38

References 39-40



Post-Test 41-42 End hour 3
Overview Orofacial Clefts
Orofacial clefts are among the most common congenital malformations worldwide. Typically, they require complex multidisciplinary treatment throughout childhood and can have lifelong medical and psychosocial implications for affected individuals. The two main types of oral clefts are cleft lip and cleft palate. Cleft lip is the congenital failure of the maxillary and median nasal processes to fuse, forming a groove or fissure in the lip. Cleft palate is the congenital failure of the palate to fuse properly, forming a grooved depression or fissure in the roof of the mouth. Clefts of the lip and palate can occur individually, together, or in conjunction with other congenital malformations.

Epidemiology
Epidemiologic studies of isolated (i.e., without other malformations or syndromes) cleft lip and/or cleft palate have been conducted worldwide, often resulting in varying prevalence rates. Differences in geographic and ethnic distributions may account for some but not all of the variations. Other factors contributing to the diverse figures are the inclusion criteria used to group cleft types (i.e., CL ± P versus CP) or define the cleft population (i.e., all cases of cleft including other birth defects versus cases of isolated cleft).
Cleft of the lip, palate, or both is one of the most common congenital abnormalities. The average prevalence of cleft lip with or without cleft palate is 7.75 per 10,000 live births in the United States and 7.94 per 10,000 live births internationally. (Tanaka, 2012)
The Centers for Disease Control and Prevention (CDC) recently estimated that each year 2,651 babies in the United States are born with a cleft palate and 4,437 babies are born with a cleft lip with or without a cleft palate. Cleft lip is more common than cleft palate. About 70% of all orofacial clefts are isolated clefts.
Cleft lip with or without cleft palate is observed more frequently in males, while isolated cleft palate is more typically seen in females (Mossey & Little, 2002). High rates of cleft lip with or without cleft palate are seen in Latin America, China, and Japan, but are relatively low in Israel, South Africa and southern Europe. Isolated cleft palate rates are high in Canada and parts of northern Europe, but low in Latin America and South Africa (Leck and Lancashire, 1995).

Embryology
Healthy structuring of the lip and palate requires a complex series of events to unfold between the 4th and 10th weeks of human embryonic development. The primitive oral cavity is surrounded by the frontonasal prominence, the paired maxillary processes, and the paired mandibular processes, all of which are dependent on the successful migration of the neural crest cells from the neural folds to the mesenchymal tissue of the early craniofacial region.
The 6th week of development results in the formation of the upper lip and the primary palate. It is important to note that at the same time, the lateral nasal process is vulnerable as it undergoes numerous cell divisions, and in fact may not properly close if growth is disturbed in any way. During the 7th week, the palatal shelves rise and fuse to form a midline epithelial seam. Following this fusion, is a differentiation of bony and muscular tissue, leading to the development of the hard and soft palates. By week 10, a separation of the oral and nasal cavities is completed, which will allow for simultaneous chewing and breathing (Sperber, 2002).
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, rationalizing 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:


  • Frontonasal Prominence (lobe a) - one from the top of the head down towards the future upper lip;

  • Maxillar Prominence (lobes b & c) - two from the cheeks, which meet the first lobe to form the upper lip;

  • Mandibular Prominence (lobes d & e) - and just below, two additional lobes grow from each side, which form the chin and lower lip;

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). (Dudas, 2007)


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. (Dudas, 2007)
Etiology
The excess or deficiency of certain nutrients has been linked to orofacial clefts in humans. These nutrients are integral in normal palatogenesis and play a role in the molecular-biological processes as substrates, cofactors, and ligands. Current research suggests that in fact a combination of genetics and environmental factors contribute to the expression of clefting of the lip and/or palate. Of particular interest is the nutritional environment of the developing embryo. This, of course, is dependent upon the mother’s nutritional intake, as well as the genes responsible for nutrient transfer and metabolism. Specifically, the embryo’s exposure and metabolism of folate and vitamin A has been studied in an effort to develop nutritional strategies for the prevention of orofacial clefting.
Folate has been identified as a one-carbon donor for DNA methylation, which allows cells to maintain control of gene expression. A folate deficiency can therefore promote aberrant gene expression, leading to the development of orofacial clefts.
Vitamin A, known as retinoic acid, is a lipid-soluble molecule that binds to specific intracellular or membrane-bound receptors. An excess of Vitamin A may saturate a cell’s receptors rendering them inactive, and resulting in cellular damage.
Although the specific manner in which palatogenesis is influenced remains unknown, several suggested pathways are implicated. These include: the homocysteine pathway, in which riboflavin, folate, pyridoxine, cobalamin, and zinc act as cofactors or substrates; the oxidative pathway, in which a balance must be met by oxidants (e.g. glucose and homocysteine) and antioxidants (e,g. ascorbic acid and glutathione); and hematopoiesis, in which iron, cobalamin, and folate play an important role. Additionally, consideration must be paid to the three ways in which nutrients can influence gene expression: directly by regulating the development of orofacial gene expression; indirectly through epigenetic events; or by affecting genomic stability.
Risk Factors
Medications

Maternal intake of vasoactive drugs, which include pseudoephedrine, aspirin, ibuprofen, amphetamine, cocaine, or ecstasy, as well as cigarette smoking, have been associated with higher risk for oral clefts (Lammer 2004). Anticonvulsant medications such as phenobarbital, trimethadione, valproate, and dilantin have been documented to increase incidence of cleft lip and/or cleft palate (Holmes 2004,). Isotretinoin (Accutane) has been identified as potential causative factors for oral clefts (Lammer 1985). An association between maternal intake of sulfasalazine, naproxen, and glucocortisoids during the first trimester has been suggested (Kallen 2003). Aminopterin (a cancer drug) has also been linked to the development of oral clefts (Warkany 1978).



Maternal Age

Several studies have reported increased risk of oral clefts with increased maternal age (Shaw 1991). However, larger studies failed to identify advanced maternal age as a risk factor for oral clefts (Vallino-Napoli 2004). Conversely, another study found a greater risk for cleft lip among younger mothers (Reefhuis, 2004).


Race

There are racial/ethnic differences in risk for oral clefts. Asians have the highest risk (14:10,000 births), followed by whites (10:10,000 births) and African Americans (4:10,000 births) (Das 1995). Among Asians, the risk for oral clefts is higher among Far East Asians (Japanese, Chinese, Korean) and Filipinos than Pacific Islanders (Yoon 1997). Amerindian populations in South America have been found to have higher rates than other “mixed“ populations (Vieira 2002).


Genetics

Genetic factors are believed to account for some defects, often in combination with one or more environmental factors. Several loci have been identified for cleft lip with or without cleft palate, and, in one case, a specific gene has also been found. In cleft palate alone, one gene has been identified, but many more are probably involved. There is evidence of two main types of cleft lip and palate in whites. The first type is controlled by a single gene, which may code for a transforming growth factor alpha (TGF-alpha) variant. The second type is multifactorial in nature. There is also some evidence that maternal and/or infant gene variations in conjunction with maternal smoking may lead to oral clefts in the infant (Lammer 2004).
Metabolism

There is some evidence that indicates that a defect in the maternal metabolism of specific dietary elements may also be a contributing factor in producing an affected child (van Rooj 2003). In this instance, the presence of a gene identified as MTHFR 677TT in conjunction with a low folate diet may lead to increased orofacial clefting. There is also an indication that even with adequate folate intake, these clefts may still occur in some cases (Lammer 2004).


Other metabolic factors that may affect the presence of orofacial clefts include maternal ability to maintain red blood cell zinc concentrations and myo-inositol concentrations (a hexahydrocycyclohexane sugar alcohol) (Krapels 2004). Maternal ability to maintain adequate levels of Vitamins B6 and B12 and fetal ability to utilize these nutrients are also seen as a factor in the development of oral clefts (van Rooj 2003). When these nutrients are not metabolized properly, errors in DNA synthesis and transcription may occur (van Rooj 2004).
Sex

Infant sex influences the risk for oral clefts. Males are more likely than females to have a cleft lip with or without cleft palate, while females are at slightly greater risk for cleft palate alone (Blanco-Davila 2003). One study indicated that family history of clefts, birth order, maternal age at birth, first-trimester maternal smoking, and alcohol consumption during pregnancy did not explain the sex difference (Abramowicz 2003).

Classification


There are several different systems for classifying orofacial clefts. Three of the most commonly used classifications systems are the Tessier classification, Van der Meulen classification, and the LAHSAL Classification.

Tessier Classification

Paul Tessier published a classification on facial clefts based on the anatomical position of the clefts. (Tessier, 1976) It is based on the consideration of the orbit, nose and mouth as key reference points through which craniofacial clefts constant flow through meridians. The cracks are numbered from 0 to 14, and the number 8 serves as the equator. Thus, the cracks from 0 to 7 represent lower hemisphere facial clefts, while those between the 9 and 14 of the top are the cranial fissures.


(Tessier, 1976)


These 15 different types of clefts can be put into 4 groups, based on their position: midline clefts, paramedian clefts, orbital clefts and lateral clefts. The Tessier classification describes the clefts at soft tissue level as well as at bone level, because it appears that the soft tissue clefts can have a slightly different location on the face than the bony clefts.

Midline clefts


The midline clefts are Tessier number 0 and number 14. The clefts comes vertically through the midline of the face. Tessier number 0 comes through the maxilla and the nose, while Tessier number 14 comes between the nose and the frontal bone.
Paramedian clefts

Tessier number 1, 2, 12 and 13 are the paramedian clefts. These clefts are quite similar to the midline clefts, but they are further away from the midline of the face. Tessier number 1 and 2 both come through the maxilla and the nose, in which Tessier number 2 is further from the midline (lateral) than number 1. Tessier number 12 is in extent of number 2, positioned between nose and frontal bone, while Tessier number 13 is in extent of number 1, also running between nose and forehead. Both 12 and 13 run between the midline and the orbit.


Orbital clefts


Tessier number 3, 4, 5, 9, 10 and 11 are orbital clefts. These clefts all have the involvement of the orbit. Tessier number 3, 4, and 5 are positioned through the maxilla and the orbital floor. Tessier number 9, 10 and 11 are positioned between the upper side of the orbit and the forehead or between the upper side of the orbit and the temple of the head. Like the other clefts, Tessier number 11 is in extent to number 3, number 10 is in extent to number 4 and number 9 is in extent to number 5.

Lateral clefts


The lateral clefts are the clefts which are positioned horizontally on the face. These are Tessier number 6, 7 and 8. Tessier number 6 runs from the orbit to the cheek bone. Tessier number 7 is positioned on the line between the corner of the mouth and the ear. A possible lateral cleft comes from the corner of the mouth towards the ear, which gives the impression that the mouth is bigger. It’s also possible that the cleft begins at the ear and runs towards the mouth. Tessier number 8 runs from the outer corner of the eye towards the ear. The combination of a Tessier number 6-7-8 is seen in the Treacher Collins syndrome. Tessier number 7 is more related to hemifacial microsomia and number 8 is more related to Goldenhar syndrome.

Van der Meulen Classification

Van der Meulen classification divides different types of clefts based on where the development arrest occurs in the embryogenesis. (Van der Meulen, 1983) A primary cleft can occur in an early stage of the development of the face (17 mm length of the embryo). The developments arrests can be divided in four different location groups: internasal, nasal, nasalmaxillar and maxillar. The maxillar location can be subdivided in median and lateral clefts.


Internasal dysplasia


Internasal dysplasia is caused by a development arrest before the union of the both nasal halves. These clefts are characterized by a median cleft lip, a median notch of the cupid’s bow or a duplication of the labial frenulum. Besides the median cleft lip, hypertelorism can be seen in these clefts. Also sometimes there can be a underdevelopment of the premaxilla.

Nasal dysplasia


Nasal dysplasia or nasoschisis is caused by a development arrest of the lateral side of the nose, resulting in a cleft in one of the nasal halves. The nasal septum and cavity can be involved, though this is rare. Nasoschisis is also characterized by hypertelorism.

Nasomaxillary dysplasia


Nasomaxillary dysplasia is caused by a development arrest at the junction of the lateral side of the nose and the maxilla, which results in a complete or non-complete cleft between the nose and the orbital floor (nasoocular cleft) or between the mouth, nose and the orbital floor (oronasal-ocular cleft). The development of the lip is normal.

Maxillary dysplasia


Maxillary dysplasia can manifest itself on two different locations in the maxilla: in the medial or the lateral part of the maxilla.


  • Median maxillary dysplasia is caused by a development failure of the medial part of the maxillary ossification centers. This results in secondary clefting of the lip, philtrum and palate. Clefting from the maxilla to the orbital floor has also been reported.




  • Lateral maxillary dysplasia is caused by a development failure of the lateral part of the maxillary ossification centers, which also results in secondary clefting of the lip and palate. Clefting of the lateral part of the lower eyelid is typical for lateral maxillary dysplasia.


LAHSAL Classification
The LAHSAL code is based upon the striped Y diagrammatic classification (Kriens, 1991). The relevant parts of the mouth are subdivided into six parts:


  • right lip

  • right alveolus

  • hard palate

  • soft palate

  • left alveolus

  • left lip



(Kriens, 1991)
The code is then written as if looking at the patient.

The first character is for the patient’s right lip and the last for the left lip.


The LAHSAL code indicates a complete cleft with a capital letter, an incomplete cleft with a lower case letter and no cleft with a dot.
For example:

Bilateral complete cleft of lip and palate: LAHSAL

Right complete cleft lip: L.....

Left incomplete cleft lip and alveolus: ....al



Incomplete hard palate, complete soft palate cleft: ..hS..

Syndromes with Associated Orofacial Clefts
Clefts of the lip and palate often co-occur with other significant congenital anomalies, especially in cases of isolated cleft palate. The association between orofacial clefts and specific genetic syndromes is between 5%-7%. Cleft lip with or without cleft palate is a common feature of more than 200 known disorders, and isolated cleft palate is a feature of more than 400 known disorders.
Several of the syndromes most commonly associated with orofacial clefting include:


  • Van Der Woude Syndrome

  • Pierre Robin Sequence

  • Treacher Collins Syndrome

  • Apert Syndrome

  • Crouzon Syndrome

  • Stickler Syndrome


Van der Woude Syndrome
Van der Woude syndrome (VWS) is a rare autosomal dominantly inherited disorder. It occurs across both genders in approximately 1 in 100,000 births. It is most commonly linked to chromosome Iq32-q41, but a second link has been attributed to Ip34. There is a 50% chance of affected individuals passing along the syndrome to their children. IRF6 has been identified as the specific gene mutated in approximately 70% of Van der Woude patients.
Clinical characteristics of Van der Woude syndrome include clefts of the lip and/or palate, lip pits, hypodontia, missing premolars, bifid uvula, ankyloglossia, hypernasal voice, as well as systemic maifestations including syndactyly. Paramedian lip pits are the most common physical manifestation, occurring in approximately 87.5% of all cases. They result when the embryonic lateral sulci fail to completely fuse. The pits are observed as transverse or circular slits atop small elevations on the surface of the lip. In many cases, minor salivary ducts open in to these pits, resulting in visible salivary discharge. This condition tends to cause a great deal of discomfort and embarrassment to the individual (Reddy et al., 2011).
Absence of the mandibular secondary premolars is frequently observed with VWS. Absent teeth have direct clinical consequences. It is therefore important to determine which teeth are missing as early as possible so that orthodontic intervention can proceed accordingly (Oberoi & Vargervik, 2005).
Pierre Robin Sequence
Pierre Robin sequence (PRS) occurs in approximately 1 in every 8500 births across both genders. A genetic link with PRS has observed when the dysregulation of SOX9 and KCNJ2 occurs. Pierre Robin sequence is characterized by mandibular micrognathia (undersized lower jaw), U-shaped cleft palate, and glossoptosis (atypical downward or posterior placement of the tongue) (Rangeeth et al., 2011).
The expression of PRS occurs during the 4th and 8th weeks of embryological development. During this period, the mandibular prominence lies between the stomodeum (a precursor to the embryonic mouth) and the first branchial groove, which outline the caudal (posterior) limits of the face. During the 6th week of development, the free ends of the mandibular arch grow and meet ventrally. This arch causes the posterior placement of the mandible, and keeps the tongue placed high in the nasopharynx. As a result, medial growth and fusion of the palatal shelves becomes impaired. Hypoplasia of the mandible occurring before the 9th week of embryologic development may therefore be an initiating factor in PRS.
Due to mandibular deficiency, newborns with PRS experience varying degrees of airway obstruction and feeding difficulties. The micrognathia and glossoptosis seen in PRS often results in poor nutrition, failure to thrive, gastroesophogeal reflux, hypoxia, hypercapnia (increased amounts of carbon dioxide), cor pulmonale (failure of the right side of the heart), neurologic impairment, and in some cases death (Gozu et al., 2010).
Additionally, many children with a diagnosis of PRS develop articulation difficulties secondary to the occurrence of micrognathia and glossoptosis. Specifically, the fricatives (‘f’,‘s’, and ‘sh’) and the plosives (‘p’ and ‘t’) are observed to be the most affected speech sounds for this population. In these cases, a speech therapist can help implement a plan to assist in remediating the resulting articulation errors (Van den Elzen et al., 2001).
Treacher Collins Syndrome
Treacher Collins syndrome (TCS) is a rare autosomal dominant disorder affecting approximately 1 in every 50,000 babies. A correlation between TCS and a mutation of the treacle gene TCOF1 has been established. Affected individuals have a 50% chance of passing along this syndrome to their children.
TCS shows a high variation in expressive phenotype, with characteristics ranging from almost severe to almost unnoticeable. Physical abnormalities of TCS include downward slanting eyes with notched lower eyelids, sunken cheekbones, sunken jawbones, broad mouth, pointed nasal prominence, high arched palate, malformed auricular pinnae, conductive hearing loss, and cleft lip and/or palate (Shete et al., 2011). Additionally, some TCS patients may exhibit a retrognathic mandible and glossoptosis resulting in airway obstruction.
Physical anomalies of the ears are a common characteristic of TCS. Abnormalities of the shape, size, and position of the auricular pinnae (outer ears) are frequently observed in this population. Other malformations include atresia of the external auditory canals, as well as irregular or absent auditory ossicles. Specifically, radiographic analysis has revealed fusion between the rudiments of the malleus and incus, partial absence of the stapes and oval window, and in some cases the complete absence of the middle ear and epitympanic space. As a result of these anomalies, TCS patients will experience bilateral conductive hearing loss.
Apert Syndrome
Apert syndrome is an autosomal dominant condition occurring in approximately 1 out of every 65,000 births. Mutations on adjacent amino acids (Ser252Trp and Pro253Arg) of human fibroblast growth factor receptor-2 (FGFR2) account for 99% of all cases of Apert syndrome. Apert syndrome accounts for 4.5% of the craniosyntosis syndromes, in which a premature fusion by ossification of one or more of the fibrous sutures in an infant’s skull occurs (Hansen et al., 2004).
Physical characteristics of Apert’s syndrome include craniosyntosis, midfacial malformations, syndactyly of the hands and feet, bifid uvula, and clefts of the soft palate (occurring in 76% of Apert’s patients). Additionally, individual’s with Apert’s syndrome frequently experience a conductive hearing loss, most likely due to malfunctioning eustachian tubes resulting in persistent otitis media with effusion (Rajenderkumar et al., 2005).
Crouzon Syndrome
Similar to Apert Syndrome, Crouzon’s Syndrome is also an autosomal dominant disorder. Occurrence within the United States is approximately 1 in 60,000 births. Crouzon’s Syndrome is caused as a result of a mutation of the human fibroblast growth factor receptor-2 (FGFR2). Approximately 4.8% of all cases of craniosyntosis are secondary to Crouzon’s Syndrome.
The primary physical characteristic of the disorder is a premature fusion of the coronal and sagittal sutures, beginning during the child’s first year of life. Other physical malformations include midfacial hypoplasia, maxillary hypoplasia, shallow orbits, mandibular prognathism, overcrowding of the upper teeth, V-shaped maxillary dental arch, bifid uvula, and cleft palate (Padmanabhan et al., 2011).
Stickler Syndrome
Stickler Syndrome is an autosomal dominant disorder of collagen connective tissue. Patients with Stickler’s syndrome are subclassified into type 1 or type 2, depending on the locus heterogeneity. Both groups demonstrate similar systemic features. Approximately 75% of patients with Stickler’s syndrome fall within the type 1 vitreous phenotype. Specifically, a distinct folded membrane is found within the retrolental space, and can be observed to be occupied with a vestigial vitreous gel.
Stickler patients falling within the type 2 vitreous phenotype demonstrate sparse and abnormally thickened fibrous bundles throughout the vitreous cavity. A diagnosis of Stickler’s syndrome should be carefully considered in cases of: infants born with spondyloepiphyseal dysplasia with myopia or deafness, infants/children demonstrating sporadic retinal detachment in association of joint hypermobility, clefting and/or deafness, as well as infants born with a family history of rhegmatogenous retinal detachment.
Stickler syndrome is most commonly expressed in ophthalmic, orofacial, auditory, and articular manifestations. Congenital nonprogressive myopia, as well as retinal detachment is common. Other phenotypic expressions include a flat midface with depressed nasal bridge, short nose, anteverted nares, and micrognathia. Midline clefting is also common, ranging in severity from a cleft of the soft palate to the Pierre Robin Sequence. Stickler syndrome patients typically experience hearing loss in the higher frequency ranges and of such a minor degree that patients are often unaware of the deficit. Secondary to the presence of clefting, patients often suffer from recurrent serous otitis media resulting in a conductive hearing deficit.

Diagnosis


Clefts in unborn babies are often detected with an ultrasound examination during a routine antenatal appointment. This antenatal scan typically takes place at around 20 weeks. The accuracy of sonography for prenatal diagnosis of cleft lip and palate is highly variable and dependent on the experience of the sonographer and the type of cleft. Reported rates of detection for cleft lip and palate range from 16% to 93% (Shaikh, 2001). Isolated cleft palate is rarely identified prenatally. Furthermore, even when a cleft lip is visualized sonographically, it is difficult to determine whether the alveolus and secondary palate are also involved. (Stroustrup Smith, 2004)
MRI is used increasingly for evaluation of fetal abnormalities that are difficult to identify on sonography alone (Levine, 2003). Fetal MRI is less dependent than sonography on optimal amniotic fluid volume, fetal position, and maternal body habitus. Additionally, visualization of small structures on MRI is not limited by bone shadowing. (Stroustrup Smith, 2004)
If a cleft lip or palate is not picked up during an antenatal appointment, the cleft is nearly always diagnosed after the baby has been born.  However, in some cases, for example a submucous cleft palate where the cleft is hidden in the lining of the mouth, a diagnosis may not be made for several months or even years, when speech problems develop.


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