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74 Cards in this Set
- Front
- Back
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What is the birth frequency of isolated nonsyndromic craniosynostosis?
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0.6/1000 live births
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Does craniosynostosis tend to have a genetic component?
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Yes. Most syndromic is genetic, AD/AR, X-linked. Over 90 syndromes related.
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What are the five most commonly identified craniosynostosis syndromes seen in plastics?
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1. Apert
2. Crouzon 3. Pfeiffer 4. Saethre-Chotzen 5. Carpenter |
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What features do the familial craniosynostoses tend to share?
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1. Midface hypoplasia
2. Cranial base growth abnormalities 3. Abnormal facies 4. Limb abnormalities |
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What growth factor is potentially implicated in syndromic craniosynostosis?
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Fibroblast growth factor and its receptor - linked to several autosomal dominant skeletal disorders including Pfeiffer, Apert, Crouzon, achondroplasia
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What are four main features of Crouzon syndrome?
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1. Premature fusion of calvarial sutures
2. Midface hypoplasia 3. Shallow orbits 4. Ocular proptosis |
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Who first described the clinical features of Crouzon syndrome? When?
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Crouzon, French neurologist, 1912
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What is the pattern of inheritance of Crouzon syndrome?
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Autosomal dominant
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What is the frequency of Crouzon syndrome (per live births)?
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1/25 000 births
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What is the most common calvarial deformity seen in Crouzon?
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Premature fusion of coronal sutures causing brachycephaly
Also scaphocephaly, trigonocephaly, cloverleaf skull |
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How do the maxilla and mandible grow in Crouzon's?
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Maxilla is hypoplastic due to cranial base suture fusion - reduced dental arch width, high arched palate
Mandible grows normally, resulting in class III malocclusion |
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Do Crouzon's patients have hand abnormalities?
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No. There are no commonly reported digital anomalies in Crouzon's.
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Who first described Apert syndrome? When?
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Apert, 1906
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What are the 4 key features of Apert's?
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Craniosynostosis, exorbitism, midface hypoplasia, symmetric syndactyly of hands and feet
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What is the indicence of Apert's? Does it show an inheritance pattern?
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1/160 000 live births
Mostly sporadic, can be autosomal dominant |
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What is the most common cranial vault deformity in Apert? What is the appearance of the skull?
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Turribrachycephaly: short AP dimension with coronal synostosis
Forehead is flat, long, with bitemporal widening and occipital flattening |
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What are three eye features of Apert's? Three nose features?
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Eyes: orbital proptosis, downslanting palpebral fissures, hypertelorism
Nose: downturned at tip, bridge depressed, septum deviated |
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What is the characteristic hand deformity of Apert's? Feet?
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fusion of second, third, and fourth fingers (with or without 4th and 5th) resulting in mid-digital hand mass; if thumb is free it is broad and deviates radially. "Mitten hand"
Feet: fusion 2nd/3rd/4th fingers |
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Are Apert's patients of normal intelligence?
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Some may have delayed development, but many have normal intelligence.
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What are four key features of Pfeiffer syndrome?
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1. Craniosynostosis
2. Broad thumbs 3. Broad great toes 4. Partial syndactyly involving second and third digits |
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What is the mode of inheritance in Pfeiffer syndrome?
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Autosomal dominant
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What are the craniofacial features of Pfeiffer's?
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Turribrachycephaly secondary to coronal +/- sagittal synostosis
Maxillary/midface hypoplasia, shallow orbits and exorbitism Hypertelorism and downslanting palpebral fissures Downturned nose with low nasal bridge |
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What are the dominant features of Saethre-Chotzen syndrome?
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Brachycephalic skull
Lowset frontal hairline Facial asymmetry with ptosis of eyelids |
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How is Saethre-Chotzen syndrome inherited?
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Autosomal dominant, wide variability in expresssion
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What is the type of synostosis in Saethre-Chotzen syndrome?
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Bicoronal synostosis results in brachycephalic skull
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What are hand findings in Saethre-Chotzen syndrome?
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Partial syndactyly in 2nd/3rd digits
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What is Carpenter syndrome?
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Rare autosomal recessive disorder with multiple craniosynostoses, partial digital syndactyly, preaxial polysyndactyly of feet
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What sutures may be implicated in Carpenter syndrome?
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Lambdoid, sagittal, coronal - thus may be brachycephalic, turricephalic
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What organ system is involved in 1/3 of Carpenter's syndrome cases?
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CVS: congenital heart defect
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How much does brain size increase in first year of life? How long does rapid brain growth continue?
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Triples in first year.
Rapid growth continues until 6-7 years of age. |
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What are the two general processes by which craniofacial growth is directed?
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1. Displacement by growing brain
2. Remodeling by stimulation of movement |
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In what order does the face mature?
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Upper face, midface, then mandible
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What are two signs of increased ICP in craniosynostosis?
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1. Papilledema
2. Thumb printing/beaten-copper appearance of skull on plain films |
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What are some ocular problems faced by children with craniosynostosis?
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Exorbitism resulting in corneal exposure, may require emergency OR
Strabismus with exotropia secondary to abnormal size/shape of orbits Abnormal development of ocular muscles Increased ICP leading to optic atrophy |
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What is the rate of hydrocephalus among children with craniosynostosis?
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4-10%, especially in Apert syndrome
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What is the presumed etiology of hydrocephalus in craniosynostosis?
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Obstruction of venous outflow results in increased venous pressure in sagittal sinus
Noncommunicating form most common |
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Where do linear craniectomy or cranial vault fragmentation fit in the management of craniosynostosis?
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Used as temporizing procedures only to protect brain and eye
Reossification usually occurs, bone of poor quality Poor results unless midface and orbit mobilization performed concurrently |
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What is the general surgical plan for children with syndromic craniosynostosis and midface deficiency?
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1. Intial fronto-orbital and cranial vault remodeling
2. Midface advancement procedure with or without distraction (Lefort III or monobloc) 3. Secondary orthognathic surgery (Lefort I, mandibular osteotomies) |
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What procedures are performed early in life (4-12 months), and which are performed later (4 to 12 years, 14-18 years) for surgical correction of craniosynostosis?
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4-12 months: suture release, vault decompression, orbital reshaping and advancement
4-12 years: midface deformities 14-18 years: jaw surgery |
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What are two options with regards to timing of midface osteotomy in craniosynostosis?
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1. Wait until all midface and lower face growth complete
2. Perform midface advancement in childhood with knowledge that second one will be necessary when mandibular growth complete |
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What are three surgical goals of fronto-orbital advancement in craniosynostosis?
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1. Release synostosed suture and decompress cranial vault
2. Reshape cranial vault and advance frontal bone 3. Advance retruded supraorbital bar to protect globe and improve aesthetics |
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Who performed the first Lefort III to attempt to correct midface deformity? Who later popularized it?
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Gillies, then popularized by Tessier
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What is the monobloc procedure? Who developed it?
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Developed by Ortiz-Monasterio
Advancement of frontal bar along with Le Fort III fragment Results in greater blood loss and infection rate that doing either separately Contraindicated in neonatal period |
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What is the procedure of choice for correcting the midface deformity of craniosynostosis? What timing is suggested?
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LeFort III via subcranial approach
Timing controversial: either early (4-7 years) or at skeletal maturity. Early may result in recurrent class III malocclusion, but also improves psychological self-esteem |
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What are some advantages of distraction osteogenesis to the one-stage lefort III or monobloc procedure?
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Advancement not limited by soft tissue envelope (up to 20mm, while standard is 6-10mm)
Less blood loss, shorter operative time No need for bone grafts Less risk of infection Less relapse |
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What is the outline of midface advancement with distraction osteogenesis?
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LeFort III/monobloc osteotomy with semiburied placement of distractor
At 5-7 days postop (soft callus formed), device advanced 1mm/day When advancement finished, wait few months for osteoid to calcify Remove distractor |
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What are disadvantages of distraction osteogenesis compared to traditional le fort III advancement?
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1. Prolonged time for distraction to complete
2. Need second procedure to remove device 3. Need to wear an external device |
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What is the most common malocclusion pattern seen in craniosynostosis syndromes?
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Class III
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What is the frequency of nonsyndromic craniosynostosis?
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04-1/1000 live births
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In what direction does the skull tend to grow when restricted by a synostosis?
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Parallel to fused suture
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Who were the first to treat craniosynostosis surgically? When?
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Lane and Lannelogue, late 1900s, strip craniectomies
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What are the four major cranial sutures?
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Metopic, sagittal, coronal, lambdoid
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Is craniosynostosis always detected at birth?
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Not always - may not be detectable until later, or very mild
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What are the four most common types of craniosynostosis patterns?
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1. Metopic synostosis, produces trigonocephaly
2. Sagittal synostosis, produces scaphocephaly 3. Unilateral coronal synostosis, produces plagiocephaly 4. Bilateral coronal synostosis, produces brachycephaly |
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Generally, at what age should surgical correction of nonsyndromic craniosynostosis occur?
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Under 1 year of age, so defects are ossified
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When dose the metopic suture close?
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7-8 months (first to close)
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What deformity results from metopic suture closure? How common is this as an isolated nonsyndromic craniosynotosis?
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Trigonocephaly ("keel" shaped)
Uncommon (<10% nonsyndromic isolated craniosynostoses) |
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What ocular and periorbital changes accompany trigonocephaly?
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Hypotelorism
Upward slanting of lateral canthi and eyebrows Flattening of supraorbital ridges |
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What are the mechanics behind the trigonocephaly that results from metopic synostosis?
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1. Flattening of frontal bones
2. Anterior displacement of coronal sutures 3. Flaring of parietal bones 4. Exaggerated by lack of lateral projection of supraorbital rims and narrowing of temporal regions |
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Once removed, how is the bifrontoparietal bone graft reshaped in metopic synostosis correction, 1. Under 1 year of age; 2. between 1-3 years; 3. over 3 years
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1. Shaping burr and radial osteotomies
2. Brittle bone, place endocranial channels or "kerfs" in bone for bending- more bone grafting needed 3. Basic fixation of segments in normal adult positions |
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What is the most common form of craniosynostosis, and what skull deformity results?
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Sagittal synostosis, causing scaphocephaly ("boat shaped")
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Is sagittal synostosis usually sporadic or inherited?
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Sporadic - only 2% genetic
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Is sagittal synostosis more prevalent in males or females?
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4:1 males to females!
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What is the basic technique of surgical correction of sagittal synostosis?
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Bifrontal, separate parietal, biparietal occipital craniotomies with reshaping of these segments
Removal of segment of midline bone to decrease AP skull length Lateral barrel staves in temporal bone region |
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How common is unilateral coronal synostosis? What skull deformity results?
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Uncommon (1/10 000)
results in plagiocephaly |
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What sequence of events results in the plagiocephaly associated with unilateral coronal synostosis?
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Fusion of coronal suture results in
1. Flattening of ipsilateral frontoparietal region 2. Bulging of ipsilateral squamous temporal bone 3. Contralateral parietal, frontal, occipital bulging |
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What radiographic abnormality, seen on plain film, is pathognomic for unilateral coronal synostosis?
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Harlequin deformity
Secondary to lack of descent of greater wing of sphenoid during development |
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What are clinically seen facial features associated with unilateral coronal synostosis?
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widening of ipsilateral palpebral fissure, superior/posterior displacement of ipsilateral orbital rim and eyebrow, deviation of nasal root toward flattened side of frontal bone; chin points to contralateral side, malar eminence projects anterior to unaffected side
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What is the skull deformity associated with bilateral coronal synostosis?
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Turribrachycephaly: shortened AP, widened mediolaterally, elongated vertically.
Orbital rims retrusive Superior frontal and squamous temporal bones protuberant, occiput flattened |
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Bilateral harlequin abnormalities are associated with which craniosynostosis?
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Bilateral coronal synostosis
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What is the least common form of craniosynostosis?
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Lambdoid synostosis
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In lambdoid synostosis, how is the ear displaced?
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Ipsilateral ear displaced potsterior and inferior
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What are potential early complications of craniosynostosis corrective surgery?
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Blood loss - potentially serious with tear of venous sinus
Air embolus - consider central line for blood volume assessment Dural tear with CSF leak Infection - associated with CSF leak and communication with nose or frontal sinus Resp complications - accidental disruption of ET tube during facial advancement |
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What are potential late complications of craniosynostosis surgery?
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Inability to fill cranial defects (esp in older children)
Transcranial plate migration in growing child Relapse of bony contour |
