This page has been created as a class project by graduate students at Northern Arizona University's Communication Sciences and Disorders program. It will serve as an information hub for the causes, symptoms and therapies associated with Crouzon Syndrome, especially from a speech and language perspective. The information here was compiled by the following students in CSD 555, Organic Disorders In Communication: Ellie Moon, Meghan Ingram, Jill Garner, Jill Stahl-Basham, Shona Granillo, and Karen Solano.
This page has been created as a class project by graduate students at Northern Arizona University's Communication Sciences and Disorders program. It will serve as an information hub for the causes, symptoms and therapies associated with Crouzon Syndrome, especially from a speech and language perspective. The information here was compiled by the following students in CSD 555, Organic Disorders In Communication: Ellie Moon, Meghan Ingram, Jill Garner, Jill Stahl-Basham, Shona Granillo, and Karen Solano.
Etiology of Crouzon Syndrome
By Meghan Ingram
Sixteen out of every million newborns will present with Crouzon syndrome. Out of all of the craniosynostosis syndromes it is the most common.
Crouzon syndrome is caused by mutations in the FGFR2 gene. This gene provides instructions for making a protein called fibroblast growth factor receptor 2. This protein signals immature cells to become bone cells during embryonic development. Mutations in the FGFR2 gene overstimulate signaling by the FGFR2 protein, which causes the bones of the skull to fuse prematurely.
In the first year of life, premature synostosis of the coronal, the sagittal, and, occasionally, the lambdoidal sutures begins and is completed by the second or third year. The order and rate of suture fusion determine the degree of deformity and disability. Growth perpendicular to that suture becomes restricted once a suture becomes fused.
The fused bones act as a single bony structure. Compensatory growth occurs at the remaining open sutures to allow continued brain growth. This often causes multiple sutural synostoses which frequently extends to premature fusion of the skull base sutures, causing midfacial hypoplasia, shallow orbits, a foreshortened nasal dorsum, maxillary hypoplasia, and occasional upper airway obstruction.
This condition is inherited in an autosomal dominant pattern. In some cases, an affected person inherits the mutation from one affected parent. Other cases result from new mutations in the gene and occur in people with no history of the disorder in their family.
http://ghr.nlm.nih.gov/condition=crouzonsyndrome
http://emedicine.medscape.com/article/942989-overview
Physical Symptoms and Traits
By Jill Garner
Many people with Crouzon's Syndrome share similar physical traits. However, they may differ in the severity of the symptoms and traits.
Because the skull bones have fused in Crouzon Syndrome, the forehead cannot grow forward as the brain grows so it becomes taller. The bones between the eyes and the upper teeth (the midface bones) are smaller so it appears the eyes are bigger.
These bones cannot grow outward so the eyes appear to bulge. The eyelid openings often slant downwards. For some kids the eyeball can bulge so far out (a condition called proptosis) that the cornea may become exposed. Because of this, when kids with this condition cry, the eyelid can temporarily get stuck behind the eyeball requiring immediate treatment.
The most common type of eye problem in kids with Crouzon is a condition called "strabismus," or an imbalance of the muscles that move the eye. This may require eye muscle balancing surgery. If this surgery is not done, many kids avoid double vision by learning not to see out of one eye. Optic nerve atrophy (weakening or wasting) may also occur which can severely limit the child's vision.
Most children with Crouzon's have ventricles in the brain that are larger than normal.
Frequently this does not cause many problems but occasionally they can get filled with so much fluid that they start putting pressure on the brain. When this happens a shunt or tube may have to be used to drain off the excess fluid.
Another condition that may occur is called a cerebellar tonsillar herniation. This happens when a part of the brain called the cerebellar tonsils get pushed through the foramen magnum where the spinal cord exits. This can cause a reduced flow of cerebral spinal fluid and cause a type of sleep apnea.
Children with Crouzon's have bigger brains. As the brain grows, the skull cannot keep up with this growth and creates increased intracranial pressure. The skull may need to be enlarged surgically depending on the intracranial pressure. This should be monitored closely by doctors at least until the teenage years.
Because of the smaller midface bones, the midface cannot grow forward very well so it is often moved forward surgically a couple of times over the lifetime of the child.
The external ears on kids with Crouzon are usually normal but the ears are positioned a little lower on the skull. The inner ears are affected by the midface hypoplasia and typically do not drain very well. This can cause frequent bouts of otitis media, generally treated by tubes in the ear. The bones of the inner ear may also be partially fused together, creating a conductive hearing loss.
Because of the midface being too small, this may create a high arch in the palate of the mouth. This may cause the floor of the nose to be pushed up, creating difficulty breathing through the nose. Also, the palate may be very narrow and crowd the upper teeth so much that they are positioned behind the lower jaw when chewing. Parents may also notice that their child's nose seems to be runny very frequently, and this can be improved through surgery.
In some children with Crouzon's there may be cervical spine issues. It may appear as if the child is always standing very straight due to no curvature of the spine.
The skin abnormality acanthosis nigricans may be observed in some. This may result in patches of darkened pigmented thickened skin on the neck and eyelids, and around the mouth.
http://www.thecraniofacialcenter.org/crouzon.html
http://www.seattlechildrens.org/medical-conditions/bone-joint-muscle-conditions/crouzon/
Communication Disorders Associated with Crouzon Syndrome
By Jill Stahl-Basham
Articulation: Crouzon Syndrome is characterized by premature fusion of bones in the skull. This can affect the maxilla and mandible. Common features include a narrow/high-arched palate, a posterior bilateral crossbite, hypodontia, and increased spacing between teeth. Underjet is common in this population.
For the above reasons, articulation errors are common in this population. Individuals with Crouzon Syndrome may have difficulties with bilabial sounds (lip closure and rounding may be difficult), /r/ and /l/, and fricatives. The difficulties with these sounds are directly attributed to abnormal tongue placement caused by the atypical maxillomandibular relationship (small upper jaw).
Language: Cognitive deficits affect some individuals with Crouzon Syndrome while some individuals with Crouzon Syndrome are of typical cognitive status. Individuals with typical cognitive status are capable of acquiring language as their age matched peers do. Hearing loss is associated with Crouzon Syndrome. A delay in language might be due to hearing loss.
Resonance: Cleft palate is associated with Crouzon Syndrome. Hypernasal speech may be present due to velopharyngeal insufficiency. This is a common characteristic of Crouzon Syndrome. Hyponasaility may be present as these individuals typically have a small nasal cavity; this makes breathing through the nose quite difficult and may result in low nasal air emission during nasal sounds.
Feeding: Cleft palate is associated with Crouzon Syndrome. In infancy, feeding becomes an issue. The speech-language pathologist will be the professional that will educate the family on safe feeding procedures. The speech-language pathologist must make decisions regarding the type of bottle and nipple to use, which flow rate to use, which position is best for the baby, and what pacing should be used. The speech-language pathologist must educate the parents about burping during and after feedings because infants with a cleft palate tend to swallow more air than typical infants.
(2007). Retrieved November 10, 2009, from http://www.linkroll.com/speech-therapy/speech-and-language-problems-presented-by-crouzon-syndrome.php
Crouzon Syndrome Treatment Options. (2009). Retrieved November 10, 2009, from http://www.seattlechildrens.org/medical-conditions/bone-joint-muscle-conditions/crouzon-treatment/
Treatments for Crouzon Syndrome
By Karen Solano
With Crouzon Syndrome, surgery is typically used to prevent the closure of sutures of the skull from damaging the brain's development. Crouzon patients typically have multiple sutures involved, most specifically bilateral coronal craniosynostoses; therefore an open operation is used rather than the strip craniectomy with helmeting.
More severely affected individuals may have closure of skull sutures prior to birth, and require early surgical intervention. Indications for early intervention include pansynostosis (closure of all skull sutures leaving no capacity of the skull to expand for brain growth) and an increase in the pressure inside the skull, which can lead to blindness, hearing loss, and death if not corrected.
The need, extent and timing for treatment of the deformities of Crouzon syndrome depend upon how severely the individual is affected and the age. In infancy, surgery may be required to release and reshape the bones of the skull, to promote normal development. Multiple staged surgeries are the general treatment plan for patients with Crouzon's Syndrome.
Orthodontics, to straighten the teeth, and jaw surgery, to place the teeth in a more normal position, may be done in childhood, the teens or even the adult years. These are complicated procedures are usually performed by specially trained craniofacial surgeons associated with major craniofacial centers. To treat the midface deficiency, plastic surgeons or oral and maxillofacial surgeons can move the lower orbit and midface bones forward (this does not need neurosurgical assistance).
There are many medical experts involved in the treatment of Crouzon Syndrome including: neurosurgeons, neuroradiologists, orthodontists, dentists and ophthalmologists. Once treated for Crouzon, most patients generally go on to live a normal lifespan and become productive and active members of mainstream society.
Medical Management
Surgery is typically used to prevent the closure of sutures of the skull from damaging the brain's development. Without surgery, blindness and mental retardation are typical outcomes. Craniofacial surgery is a discipline of plastic surgery and oral and maxillofacial surgery.
To move the orbits forward, plastic surgeons or oral and maxillofacial surgeons work with neurosurgeons to expose the skull and orbits and reshape the bone. To treat the midface deficiency, plastic surgeons or oral and maxillofacial surgeons can move the lower orbit and midface bones forward (this does not need neurosurgical assistance).
For jaw surgery, either plastic surgeons or oral and maxillofacial surgeons have experience to perform these operations. It is rare to wear a custom-fitted helmet (or cranial band) for several months after surgery as that is only for single-suture "strip craniectomy" repair. Crouzon patients tend to have multiple sutures involved, most specifically bilateral coronal craniosynostoses, therefore an open operation is used rather than the strip craniectomy with helmeting.
Once treated for the cranial vault symptoms, Crouzon patients generally go on to live a normal lifespan.
Medical Care
A high prevalence of visual impairment in patients with craniosynostotic syndromes such as Crouzon syndrome was reported; almost half of the cases were due to potentially correctable causes, including amblyopia and ametropia. Optic atrophy remains an important cause of visual impairment.
Early detection of eye problems to reduce amblyopia by correction of refractory errors and timely treatment of strabismus and patching is indicated. Optic atrophy remains an important cause of visual impairment before decompressive craniectomy. To relieve airway obstruction, a nasal continuous positive airway pressure device may be needed.
Close otologic and audiologic follow-up is indicated to detect sensorineural hearing loss. Management of speech may be necessary.
What kind of treatment is available for my child?
The need, extent and timing for treatment of the deformities of Crouzon syndrome depend upon how severely the individual is affected and the age. For the infant, surgery may be required to release and reshape the bones of the skull, so that they may grow more normally.
Orthodontics, to straighten the teeth, and jaw surgery, to place the teeth in a more normal position, may be done in childhood, the teens or even the adult years. These are complicated operations usually performed by specially trained craniofacial surgeons associated with major craniofacial centers.
Diagnosis And Treatment
After examining an infant, it is easy to diagnose Crouzon Syndrome. Xrays, magnetic resonance imaging (MRIs) and genetic testing are used to confirm the diagnosis.
Surgery is used to prevent the cranial sutures from fusing and damaging brain development. Besides cranial surgical intervention, extensive facial, orthodontic and cosmetic surgery is also required.
There are many medical experts involved in the treatment of Crouzon Syndrome - neurosurgeons, neuroradiologists, orthodontists, dentists and ophthalmologists.