Abstract
A benign Chiari I malformation (CM I) is one with minimal or no classical symptoms at presentation and no imaging evidence of syringomyelia, hydrocephalus, or spinal cord signal change. Published literature about this entity is limited and based primarily on retrospective cohort studies. Benign CM I likely represents about 40% of all CM I and has a favorable clinical course. In the available literature, rate of new syrinx development is about 2%, while 9% of patients worsen clinically, and 4% of patients require posterior fossa decompression. We recommend clinical and radiographic follow-up of patients with benign CM I.
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References
Aitken LA, Lindan CE, Sidney S, Gupta N, Barkovich AJ, Sorel M, et al. Chiari type I malformation in a pediatric population. Pediatr Neurol. 2009;40:449–54.
Barkovich AJ, Wippold FJ, Sherman JL, Citrin CM. Significance of cerebellar tonsillar position on MR. AJNR Am J Neuroradiol. 1986;7:795–9.
Kahn EN, Muraszko KM, Maher CO. Prevalence of Chiari I malformation and Syringomyelia. Neurosurg Clin N Am. 2015;26:501–7.
Meadows J, Kraut M, Guarnieri M, Haroun RI, Carson BS. Asymptomatic Chiari Type I malformations identified on magnetic resonance imaging. J Neurosurg. 2000;92:920–6.
Morris Z, Whiteley WN, Longstreth WT, Weber F, Lee Y-C, Tsushima Y, et al. Incidental findings on brain magnetic resonance imaging: systematic review and meta-analysis. BMJ. 2009;339:b3016.
Nishizawa S, Yokoyama T, Yokota N, Tokuyama T, Ohta S. Incidentally identified syringomyelia associated with Chiari I malformations: is early interventional surgery necessary? Neurosurgery. 2001;49:637–40; discussion 640–1.
Strahle J, Muraszko KM, Kapurch J, Bapuraj JR, Garton HJL, Maher CO. Natural history of Chiari malformation Type I following decision for conservative treatment. J Neurosurg Pediatr. 2011;8:214–21.
Vernooij MW, Ikram MA, Tanghe HL, Vincent AJPE, Hofman A, Krestin GP, et al. Incidental findings on brain MRI in the general population. N Engl J Med. 2007;357:1821–8.
Haines SJ, Berger M. Current treatment of Chiari malformations types I and II: a survey of the Pediatric Section of the American Association of Neurological Surgeons. Neurosurgery. 1991;28:353–7.
Schijman E. History, anatomic forms, and pathogenesis of Chiari I malformations. Childs Nerv Syst ChNS Off J Int Soc Pediatr Neurosurg. 2004;20:323–8.
Benglis D, Covington D, Bhatia R, Bhatia S, Elhammady MS, Ragheb J, et al. Outcomes in pediatric patients with Chiari malformation Type I followed up without surgery. J Neurosurg Pediatr. 2011;7:375–9.
Chavez A, Roguski M, Killeen A, Heilman C, Hwang S. Comparison of operative and non-operative outcomes based on surgical selection criteria for patients with Chiari I malformations. J Clin Neurosci Off J Neurosurg Soc Australas. 2014;21:2201–6.
Leon TJ, Kuhn EN, Arynchyna AA, Smith BP, Tubbs RS, Johnston JM, et al. Patients with “benign” Chiari I malformations require surgical decompression at a low rate. J Neurosurg Pediatr. 2019;23(4):498–506.
Novegno F, Caldarelli M, Massa A, Chieffo D, Massimi L, Pettorini B, et al. The natural history of the Chiari type I anomaly. J Neurosurg Pediatr. 2008;2:179–87.
Pomeraniec IJ, Ksendzovsky A, Awad AJ, Fezeu F, Jane JA. Natural and surgical history of Chiari malformation Type I in the pediatric population. J Neurosurg Pediatr. 2016;17:343–52.
Whitson WJ, Lane JR, Bauer DF, Durham SR. A prospective natural history study of nonoperatively managed Chiari I malformation: does follow-up MRI surveillance alter surgical decision making? J Neurosurg Pediatr. 2015;16:159–66.
Wu YW, Chin CT, Chan KM, Barkovich AJ, Ferriero DM. Pediatric Chiari I malformations: do clinical and radiologic features correlate? Neurology. 1999;53:1271–6.
Massimi L, Caldarelli M, Frassanito P, Di Rocco C. Natural history of Chiari type I malformation in children. Neurol Sci Off J Ital Neurol Soc Ital Soc Clin Neurophysiol. 2011;32(Suppl 3):S275–7.
Killeen A, Roguski M, Chavez A, Heilman C, Hwang S. Non-operative outcomes in Chiari I malformation patients. J Clin Neurosci Off J Neurosurg Soc Australas. 2015;22:133–8.
Langridge B, Phillips E, Choi D. Chiari malformation type 1: a systematic review of natural history and conservative management. World Neurosurg. 2017;104:213–9.
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Alford, E.N., Zimmerman, K., Rocque, B.G. (2020). Benign Chiari I Malformation. In: Tubbs, R., Turgut, M., Oakes, W. (eds) The Chiari Malformations. Springer, Cham. https://doi.org/10.1007/978-3-030-44862-2_30
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DOI: https://doi.org/10.1007/978-3-030-44862-2_30
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