Craniosynostosis Moderator – Dr S S Kale Dr H K G. Presenter - Mansukh Sangani 10/10/2012 Craniosynostosis 1 Craniosynostosis Definition – Characteristic skull deformities that occur as a result of premature fusion of various cranial vault sutures. Craniosynostosis are frequently associated with impaired central nervous system functions due to raised intra-cranial pressure, hydrocephalus, and brain anomalies. Incedence-1 / 2000-2500 live birth. Males - sagittal and metopic stenosis Females - coronal 10/10/2012 Craniosynostosis 2 History of craniosynostosis Otto ( 1830) coined the term craniosynostosis. Virchow : Classify the different types of skull deformity. L.C. Lane: 1st surgical procedure to release stenosed suture Lannelogue (1890) :- performed B/L strip craniectomies Paul Tessier - father of modern craniofacial Surgery. - First to attempt major surgical procedures on the craniofacial skeleton. 10/10/2012 Craniosynostosis 3 Pathophysiology Normal Infant skull-flexible enough to get through vagina and expansile enough to accommodate rapidly growing brain. The calvarial sutures serve 2 important functions- (a) maintenance of head malleability,(b) growth sites The cranial base was proposed as the primary locus of the abnormality in children with multi sutural craniosynostosis and may not be the primary anomaly in bicoronal or sagittal craniosynostosis. 10/10/2012 Craniosynostosis 4 10/10/2012 Craniosynostosis 5 Brain Growth At term nearly 40% of adult brain volume, and This increases to 80% by 3 years of age and continues to grow until the age of 12 yrs. The cranium At term - 40% of adult size and by 7 years of age - increases to 90%. Principles and practice of pediatric neurosurgery. New York: Thieme Medical, 1999:219-42. 10/10/2012 Craniosynostosis 6 Timing of closer of sutures & Fontanelles Sutures & Fontanelles Timing of closer Metopic Suture 9 months - 2 year Coronal , Sagittal and Lamdoid suture 40 years Anteior fonanelles 18-24 months Posterior fontanelles 3 - 6 months Mastoid fontanelles 1 year Sphenoid fontaneles 2-3 months Rodger E, Hall CM. Craniosynostosis. Clin Radiol 2002;57:94 10/10/2012 Craniosynostosis 7 Eology of Craniosynostosis Exact etiology is not known Sporadic in most instances Potential risk factors :- - white maternal race, -advanced maternal age, -male infant sex, -maternal smoking, -maternal residence at high altitude, -use of amine containing drugs (e.g., nitrofurantoin, chlordiazepoxide, chlorpheniramine) -certain paternal occupations (e.g., agriculture and forestry, mechanics) -fertility treatments. 10/10/2012 Craniosynostosis 8 Familial Nonsyndromic craniosynostosis, - Transmitted as an Autosomal Dominant disorder - Affect 2-6 % with sagittal synostosis & 8-14% with coronal synostosis Fibroblast growth factor and fibroblast growth factor receptor (FGFR) : regulate fetal osteogenic growth and possibly influence fetal suture patency. Mutation in gene coding for FGFR1 -Pfeiffer’s syndrome FGFR2 -Apert’s syndrome and Crouzon’s syndrome 10/10/2012 TWIST – SaethreCraniosynostosis chotzen syndrome 9 Theories of Cranoisynostosis Sommering( 1839) –noted that bone growth in skull primarily occurs at suture line and if it prematurely fused, an abnormal skull shape developed and skull growth restricted. Virchow(1821) and Otto(1830)- similar observation were made and they noted restriction of growth adjacent to suture and compensatory growth occurred at elsewhere in skull to accommodate growing brain . Jane JA: the major cause of the global cranial deformity was compensatory overgrowth at adjacent sutures. 10/10/2012 Craniosynostosis 10 Theories of Craniosynostosis Moss(1959) – described functional matrix theory. According to this theory cranial base abnormality was the primary pathological process and cranial vault suture abnormality was secondary as cranial base mature embryologically before cranial vault. Persson (1979) – cranial vault suture pathology may be primary in the development of synostosis leading to cranial base and facial deformity. Marsh and Vannier(1986) –following cranioplasty in patients with individual suture craniosynostosis, surgery altered only the cranial vault structure, the previously developed cranial base abnormalities were not ameliorated . 10/10/2012 Craniosynostosis 11 Classificaon of Craniosynostosis Primary Simple(single suture) : - Nonsyndromic: sagittal, coronal, metopic, lambdoid Compound ( ≥2 suture): -Nonsyndromic: bicoronal Syndromic: Crouzon’s disease, Apert’s syndrome, Pfeiffer’s disease, Saethre-Chotzen syndrome Secondary Metabolic disorders: - e.g., hyperthyroidism (bone mature faster ) Malformations : - e.g. holoprosencephaly, shunted hydrocephalus, microcephaly, encephalocele. Exposure of fetus: - e.g. valproic acid, phenytoin. Mucopolysaccharidosis : - e.g., Hurler’s syndrome, Morquio’s syndrome. Albright AL, Pollack IF, Adelson PD, eds. Principles and practice of pediatric neurosurgery. New York: Thieme Medical, 1999:221, and Aviv RI, Rodger E, Hall CM. Craniosynostosis. Clin Radiol 10/10/2012 2002;57:94. Craniosynostosis 12 Primary vs secondary craniosynostosis Primary Secondary Primary defect of ossification Secondary to brain suture growth is altered malformation head frequently asymmetric Head symetric the brain continues to grow growth of brain is impaired in areas where sutures are neurologically abnormal open usually most individuals are normal No benifit of surgery neurologically benefit from surgery 10/10/2012 Craniosynostosis 13 TYPE OF CRANIOSYNOSTOSIS CHARACTERISTIC HEAD SHAPE Single-Suture Synostosis Sagittal Scaphocephaly(Dolichocephaly) Coronal Anterior plagiocephaly, Metopic Trigonocephaly Lambdoid Posterior plagiocephaly Double-Suture Synostosis Bicoronal Anterior brachycephaly Bilambdoid Posterior brachycephaly Saggittal plus metopic Scaphocephaly Complex Multisuture Synostosis Bicoronal, sagittal,metopic Turribrachycephaly Multisuture, pansynstosis cloverleaf (Kleeblattschadel) 10/10/2012 Craniosynostosis 14 10/10/2012 Craniosynostosis 15 Types of craniosynostosis (A) Sagittal craniosynostosis (Scaphocephaly, dolichocephaly )- Most common – 40-55%, 1 in 5000 live birth Male : Female = 3:1, Skull shape characterized by biparietal narrowing, ridging of the sagittal suture, and bilateral bulging of the frontal and occipital region or both. 10/10/2012 Craniosynostosis 16 Sagi:al craniosynostasis Clinical photograph-Lateral and Superior view of a child with sagittal craniosynostosis demonstrating frontal and occipital bossing. 10/10/2012 Craniosynostosis 17 Superior view of a 3-dimensional CT scan demonstrating a fused sagittal suture with frontal bossing and patent coronal sutures. 10/10/2012 Craniosynostosis 18 Metopic synostosis Also known as trigonocephaly, Incidence – 4-10 % , M > F The distance between the medial canthi of the eyes is reduced. metopic synostosis. 1, Ridging of metopic suture. 2, Temporal narrowing. 3, Patent coronal suture displaced anteriorly. 4, Compensatory bulging of the parieto-occipital region. 5, Narrowed bizygomatic dimension. 6, Posterior displacement of the superolateral orbital rim. 10/10/2012 Craniosynostosis 19 Metopic synostosis 10/10/2012 Craniosynostosis 20 Coronal craniosynostosis Second most common type (20 -25 %) 1/10,000 live births female > male with ration of 2 : 1 Two types :- i) Bilateral coronal cranosynostosis- Brachycephaly ii) unilateral coronal cranosynostos- Anterior plegiocephaly 10/10/2012 Craniosynostosis 21 Unilateral coronal synostosis •prematurely fused one coronal suture, • flattening of the ipsilateral frontal and parietal bones, •bulging of the contralateral frontal and parietal bones •bulging of the ipsilateral squamous portion of the temporal bone, •ipsilateral ear displaced anteriorly compared with the contralateral ear. •radiographic findings include the “harlequin” orbit deformity ( elevation of supra orbital margin )due to elevation of the greater and lesser wings of the sphenoid 10/10/2012 Craniosynostosis 22 Bilateral coronal synostosis 1, Fused bilateral coronal suture. 2, Recessed superior orbital rim. 3, Prominent frontal bone. 4, Flattening of occiput. 5, Anteriorly displaced skull vertex. 6, Shortened anterior cranial fossa. 7, Harlequin deformity of greater wing of sphenoid. 8, Protrusion of squamous portion of temporal bone. 10/10/2012 Craniosynostosis 23 Lambdoid synostosis Represents 2- 4% , prevalence of 1 / 150,000 live births unilateral fusion - Posterior plegiocephaly bilateral fusion - Posterior brachycephaly Unilateral posterior plegiocephaly should be differentiated from positional plagiocephaly 10/10/2012 Craniosynostosis 24 Oxycephaly Turricephaly ( high head syndriome) Fused coronal and sagittal suture results in a an abnormally high conical head shape with bossing in the region of the anterior fontanelle Seen in syndromic craniosynostosis 10/10/2012 Craniosynostosis 25 Cloverleaf skull deformity , Pansynostosis/multiple suture synostosis head shaped like a cloverleaf (Kleeblattschadel) three bulges-two temporal and top pronounced constrictions in both sylvian fissures 10/10/2012 Craniosynostosis 26 Craniosynostosis syndrome 10-20 % of cases Autosomal Dominant Linked to Chromosome 10 Multi-sutural, complex craniosynostosis If a suture is fused, check hands, feet, big toe and thumb 10/10/2012 Craniosynostosis 27 Craniosynostosis syndrome Crouzon’s syndrome one in 25,000 live births 5 % of cases of craniosynostosis Autosomal-dominant pattern. paternal age older than 35 years. Normal intellect