Craniosynostosis: Understanding the Misshaped Head

HomeRadioGraphicsVol. 41, No. 2 PreviousNext Pediatric ImagingFree AccessRadioGraphics Fundamentals | Online PresentationCraniosynostosis: Understanding the Misshaped HeadJuan Camilo Márquez, Cherina Herazo Bustos , Matthias W. WagnerJuan Camilo Márquez, Cherina Herazo Bustos , Matthias W. WagnerAuthor AffiliationsFrom the Department of Radiology, McGill University, Montreal, Québec, Canada (J.C.M.); Department of Radiology, Clínica Universitaria Colombia, Street 66 23-46, Bogotá 111321, Colombia (C.H.B.); and Department of Diagnostic Imaging, Division of Neuroradiology, The Hospital for Sick Children, University of Toronto, Toronto, Ontario, Canada (M.W.W.).Address correspondence to C.H.B. (e-mail: [email protected]).Juan Camilo MárquezCherina Herazo Bustos Matthias W. WagnerPublished Online:Mar 1 2021https://doi.org/10.1148/rg.2021200127MoreSectionsPDF ToolsImage ViewerAdd to favoritesCiteTrack CitationsPermissionsReprints ShareShare onFacebookTwitterLinked In AbstractThe full digital presentation is available online.Craniosynostosis is defined as the premature closure of one or more cranial sutures, which alters the configuration of the child's head (Figure). The morbidity and mortality are related to intracranial hypertension, hydrocephalus, Chiari 1 deformity, upper airway obstructions, and developmental delay, especially in syndromic cases. Eighty-five percent of cases are nonsyndromic, and of these, 75% are single-suture synostoses and nearly 60% of those are sagittal synostosis.Sagittal synostosis (scaphocephaly) typically spares the skull base. It manifests with frontal and occipital prominence, a narrow and elongated skull, a flat vertex, and ridging of the suture.Figure. Three-dimensional CT reconstructions show the types of alterations of head shape in children.Figure.Download as PowerPointOpen in Image Viewer The second most common type is coronal synostosis, which can be unilateral or bilateral, with the former being more common. This deformity is called anterior plagiocephaly with ipsilateral exophthalmos, frontal bone flattening, and contralateral bossing. Bicoronal synostosis (brachycephaly) manifests with a widened transverse diameter of the skull, harlequin deformity, and hypertelorism.Metopic synostosis (trigonocephaly) is less common. Triangular or pearlike shape, parieto-occipital bossing, and narrow anterior cranial fossa are characteristic cranial features. Orbital features include quizzical orbits and lateral orbital hypoplasia.The least common type is lambdoid synostosis (posterior plagiocephaly). It is characterized by occipitoparietal flattening, mastoid bulging, and contralateral occipitoparietal and frontal bossing. The keys to differentiate lambdoid synostosis from positional plagiocephaly are the trapezoidal shape of the skull and posterior displacement of the ear.Syndromic synostoses are caused by specific mutations and manifest with multiple systemic alterations. Apert syndrome is caused by a mutation in the FGFR2 gene. The craniofacial findings include coronal synostosis (rarely, cloverleaf skull), midface hypoplasia, and hypertelorism. Further musculoskeletal anomalies include syndactyly, vertebral fusion (often at C5-C6), and joint deformities.Crouzon syndrome is caused by mutations of the FGFR2 or FGFR3 gene. Craniofacial features are coronal synostosis (the sagittal and lambdoid sutures can also be affected), midface hypoplasia, and exophthalmos. Systemic features include hearing loss due to auditory meatus atresia, orbital defects, and cervical spine fusion.Pfeiffer syndrome is caused by mutations in the FGFR1 or the FGFR2 gene. There are three types, with different degrees of fusion of the coronal and sagittal sutures. Type 1 is the classic form. Frequent manifestations include midface hypoplasia, hypertelorism, broad thumbs and toes, brachydactyly, and syndactyly. Type 2 manifests with cloverleaf skull, extreme proptosis, and ankylosis or synostosis of elbows. Type 3 is similar but without the cloverleaf skull.The neuroradiologist's role in pediatric assessment is the evaluation of the head shape with regard to premature fusion of the sutures, which can be depicted at CT. The radiology report should include a section about the vascular anatomy, including the course of the venous sinuses, large scalp or bridging veins (relevant for surgical planning), venous thrombosis, and arterial variants. In addition, craniovertebral junction anomalies and signs of increased intracranial pressure need to be assessed carefully. Postoperative complications such as stroke, hemorrhage, cerebrospinal fluid leaks, intracranial collections, and venous damage or thrombosis must be ruled out.In the online presentation, the anatomy and embryology of the skull and the main craniosynostoses are presented, as well as the protocol for low-dose CT.Suggested ReadingsPresented as an education exhibit at the 2019 RSNA Annual Meeting.All authors have disclosed no relevant relationships.Suggested ReadingsBadve CA, Mallikarjunappa MK, Iyer RS, Ishak GE, Khanna PC. Craniosynostosis: imaging review and primer on computed tomography. Pediatr Radiol 2013;43(6):728–742; quiz 725–727. Crossref, Medline, Google ScholarBronfin DR. Misshapen heads in babies: position or pathology? Ochsner J 2001;3(4):191–199. Medline, Google ScholarD'Apolito G, Colosimo C, Cama A, Rossi A. Craniosynostoses. In: Rossi A, ed. Pediatric Neuroradiology. Berlin, Germany: Springer, 2015; 1–40. Crossref, Google ScholarKim HJ, Roh HG, Lee IW. Craniosynostosis: Updates in Radiologic Diagnosis. J Korean Neurosurg Soc 2016;59(3):219–226. Crossref, Medline, Google ScholarWagner MW, Poretti A, Benson JE, Huisman TA. Neuroimaging Findings in Pediatric Genetic Skeletal Disorders: a Review. J Neuroimaging 2017;27(2):162–209. Crossref, Medline, Google ScholarArticle HistoryReceived: May 28 2020Revision requested: June 26 2020Revision received: July 23 2020Accepted: Aug 4 2020Published online: Mar 01 2021Published in print: Mar 2021 FiguresReferencesRelatedDetailsCited ByRadiopaedia.orgZentoutSofiane2022Accompanying This ArticleCraniosynostosis: Understanding the Misshaped HeadMar 1 2021Default Digital Object SeriesRecommended Articles Imaging of Skeletal Disorders Caused by Fibroblast Growth Factor Receptor Gene MutationsRadioGraphics2017Volume: 37Issue: 6pp. 1813-1830US of Pediatric Superficial Masses of the Head and NeckRadioGraphics2018Volume: 38Issue: 4pp. 1239-1263MR Imaging of the Fetal Face: Comprehensive ReviewRadioGraphics2018Volume: 38Issue: 3pp. 962-980Imaging Spectrum of Calvarial AbnormalitiesRadioGraphics2021Volume: 41Issue: 4pp. 1144-1163Case 280: TrichopoliodystrophyRadiology2020Volume: 296Issue: 2pp. 463-467See More RSNA Education Exhibits Craniosynostosis: Understanding the Misshaped HeadDigital Posters2019Imaging of Carniosynostosis and Its Reconstructive SurgeryDigital Posters2020Sonographic Assessment of Cranial Sutures: A Safe Screening Tool to Rule Out Craniosynostosis in ChildrenDigital Posters2019 RSNA Case Collection Apert's SyndromeRSNA Case Collection2021Enlarged Parietal Foramina RSNA Case Collection2022Dysostosis Multiplex (Hurler's Syndrome)RSNA Case Collection2021 Vol. 41, No. 2 Slide PresentationMetrics Altmetric Score PDF download