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Neuropediatrics 2016; 47(05): 293-307
DOI: 10.1055/s-0036-1584563
Review Article
Georg Thieme Verlag KG Stuttgart · New York

Chiari Type 1 Deformity in Children: Pathogenetic, Clinical, Neuroimaging, and Management Aspects

Andrea Poretti   *
1   Section of Pediatric Neuroradiology, Division of Pediatric Radiology, Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States
,
Ramy Ashmawy   *
2   Department of Neuroradiology, Hospital for Sick Children, University of Toronto, Toronto, Ontario, Canada
,
Tomas Garzon-Muvdi
3   Division of Pediatric Neurosurgery, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States
,
George I. Jallo
3   Division of Pediatric Neurosurgery, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States
4   Pediatric Neurosurgery and Institute for Brain Protection Sciences, Johns Hopkins All Children's Hospital, St. Petersburg, Florida, United States
,
Thierry A. G. M. Huisman   *
1   Section of Pediatric Neuroradiology, Division of Pediatric Radiology, Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States
,
Charles Raybaud   *
2   Department of Neuroradiology, Hospital for Sick Children, University of Toronto, Toronto, Ontario, Canada
› Author Affiliations
Further Information

Publication History

04 February 2016

27 April 2016

Publication Date:
23 June 2016 (online)

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Abstract

Our understanding of cerebellar tonsillar herniation evolved over time and nowadays various pathomechanisms have been proposed. Causes of tonsillar herniation share a discrepancy between content (fore- and hindbrain) and container (supratentorial cranial vault, posterior fossa), may be associated with abnormalities of the craniocervical junction, and may have a developmental or acquired nature. In tonsillar herniation, the hindbrain is not malformed but deformed. Accordingly, “Chiari type 1 deformity,” not “Chiari type 1 malformation” is the correct term to characterize primary tonsillar herniation. Chiari type 1 deformity is commonly seen in pediatric neurology, neuroradiology, and neurosurgery and may have various clinical presentations depending on patient age. In addition, Chiari type 1 deformity is increasingly found by neuroimaging studies as an incidental finding in asymptomatic children. An accurate and reliable selection of patients based on clinical and neuroimaging findings is paramount for the success of neurosurgical treatment. Future studies are needed to provide selection criteria with a higher sensitivity and specificity.

Keywords

Chiari type 1 - children - cerebellum - neuroimaging - neurosurgery

* The authors Andrea Poretti, Ramy Ashmawy, Thierry A. G. M. Huisman, and Charles Raybaud contributed equally to the article.


 

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