PREVALENCE OF CHIARI TYPE I MALFORMATION ON CERVICAL MAGNETIC RESONANCE IMAGING: A RETROSPECTIVE STUDY
Objectives: Chiari malformation is characterized by caudal herniation of cerebellar tonsils from foramen magnum into the cervical canal on radiological images. Type I Chiari malformation is the herniation of cerebellar tonsils more than 3 mm which does not cause any symptoms until adulthood. In this study, we aimed to investigate the prevalence of Chiari type I malformation.Methods: In this retrospective study, cervical magnetic resonance images taken between 2013 and 2015 were retrospectively analyzed. The patients were 18–70 year old males and females. Type I Chiari malformation was defined as an inferior displacement of the cerebellar tonsils more than 3 mm below the opisthion-basion line. The patients with intracranial lesions, hydrocephalus or previous craniotomy were excluded from the study.Results: The prevalence of Chiari type I malformation was found as 4% when both genders were taken into consideration. The prevalence was 3.3% in females and 0.7% in males. Chiari type I malformation was associated with syringomyelia in 0.5% of females and 0.2% of males. In the present study, concomitant syringomyelia was observed in 0.7% of the patients. On the other hand, incidence of Chiari type I malformation was found relatively higher in the patients with scoliosis (15.4%). The ratio of this co-occurrence was higher in females (11.4%) when compared to the males (4%).Conclusion: In the present study, the prevalence of Chiari type I malformation was investigated in a large population, consisting of 2480 individuals, and its association with syringomyelia and scoliosis.
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- Elam MJ, Vaughn JA. Chiari type I malformations in young adults:
- implications for the college health practitioner. J Am Coll Health
- ;59:757–9.
- Fernandes YB, Ramina R, Campos-Herrera CR, Borges G.
- Evolutinary hypothesis for Chiari type I malformation. Med
- Hypotheses 2013;81:715–9.
- Fernández AA, Guerrero AI, Martínez MI, Vázquez ME, Fernández
- JB, Chesa I Octavio E, Labrado Jde L, Silva ME, de Araoz MF,
- García-Ramos R, Ribes MG, Gómez C, Valdivia JI, Valbuena RN,
- Ramón JR. Malformations of the craniocervical junction (Chiari type
- I and syringomyelia: classification, diagnosis and treatment). BMC
- Musculoskelet Disord 2009;17:10:S1.
- Godzik J, Kelly MP, Radmanesh A, Kim D, Holekamp TF, Smyth
- MD, Lenke LG, Shimony JS, Park TS, Leonard J, Limbrick DD.
- Relationship of syrinx size and tonsillar descent to spinal deformity
- in Chiari malformation type I with associated syringomyelia. J
- Neurosurg Pediatr 2014;13:368–74.
- Isik N, Elmaci I, Isik N, Cerci SA, Basaran R, Gura M, Kalelioglu M.
- Long-term results and complications of the syringopleural shunting
- for treatment of syringomyelia: a clinical study. Br J Neurosurg 2013;
- :91–9.
- Leikola J, Haapamäki V, Karppinen A, Koljonen V, Hukki J,
- Valanne L, Koivikko M. Morphometric comparison of foramen
- magnum in non-syndromic craniosynostosis patients with or without
- Chiari I malformation. Acta Neurochir (Wien) 2012;154:1809–13.
- 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.
- Oldfield EH, Muraszko K, Shawker TH, Patronas NJ. Pathophysiology
- of syringomyelia associated with Chiari 1 malformation of cerebellar
- tonsils. J Neurosurg 1994;80:3–15.
- Aiken AH, Hoots JA, Saindane AM, Hudgins PA. Incidence of cerebellar
- tonsillar ectopia in idiopathic intracranial hypertension: a
- mimic of the Chiari I malformation. AJNR Am J Neuroradiol 2012;
- :1901–6.
- Erdogan E, Cansever T, Secer HI, Temiz C, Sirin S, Kabatas S,
- Gonul E. The evaluation of surgical treatment options in the Chiari
- malformation type I. Turk Neurosurg 2010;20:303–13.
- Hwang HS, Moon JG, Kim CH, Oh SM, Song JH, Jeong JH. The
- comparative morphometric study of the posterior cranial fossa: what
- is effective approaches to the treatment of Chiari malformation type
- I. J Korean Neurosurg Soc 2013;54:405–10.
- Kim IK, Wang KC, Kim IO, Cho BK. Chiari 1.5 malformation:: an
- advanced form of Chiari I malformation. J Korean Neurosurg Soc
- ;48:375–9.
- Oakes WJ, Tubbs RS. Chiari malformations. In: Winn HR, editor.
- Youmans neurological surgery. A comprehensive reference guide to
- the diagnosis and management of neurosurgical problems. 5th ed.
- Philadelphia: Saunders; 2004. p. 3347–61.
- Noudel R, Jovenin N, Eap C, Scherpereel B, Pierot L, Rousseaux P.
- Incidence of basioccipital hypoplasia in Chiari malformation type I:
- comparative morphometric study of the posterior cranial fossa. J
- Neurosurg 2009;111:1046–52.
- Koyanagi I, Houkin K. Pathogenesis of syringomyelia associated
- with Chiari type 1 malformation: review of evidences and proposal of
- a new hypothesis. Neurosurg Rev 2010;33:271–84.
- Zhu Z, Sha S, Sun X, Liu Z, Yan H, Zhu W, Wang Z, Qiu Y.
- Tapering of the cervical spinal canal in patients with distended or
- nondistended syringes secondary to Chiari type I malformation.
- AJNR Am J Neuroradiol 2014;35:2021–6.
- Smith BW, Strahle J, Bapuraj JR, Muraszko KM, Garton HJ, Maher
- CO. Distribution of cerebellar tonsil position: implications for
- understanding Chiari malformation. J Neurosurg 2013;119:812–9.
- Kahn EN, Muraszko KM, Maher CO. Prevalence of Chiari I malformation
- and syringomyelia. Neurosurg Clin N Am 2015;26:501–7.
- Leikola J, Koljonen V, Valanne L, Hukki J. The incidence of Chiari
- malformation in nonsyndromic, single suture craniosynostosis. Childs
- Nerv Syst 2010;26:771–4.
- Elster AD, Chen MY. Chiari I malformations: clinical and radiologic
- reappraisal. Radiology 1992;183:347–53.
- Milhorat TH, Chou MW, Trinidad EM, Kula RW, Mandell M,
- Wolpert C, Speer MC. Chiari I malformation redefined: clinical and
- radiographic findings for 364 symptomatic patients. Neurosurgery
- ;44:1005–17.
- Vernooij MW, Ikram MA, Tanghe HL, Vincent AJ, Hofman A,
- Krestin GP, Niessen WJ, Breteler MM, van der Lugt A. Incidental findings on brain MRI in general populatio. N Engl J Med 2007;357:
- –8.
- Banik R, Lin D, Miller NR. Prevalence of Chiari I malformation and
- cerebellar ectopia in patients with pseudotumor cerebri. J Neurol Sci
- ;247:71–5.
- National Institude of Neurological Disorders and Strokes (NINDS).
- Chiari malformation fact sheet. [Internet]. Bethesda (MD): National
- Institutes of Health (NIH) Neurological Institute; [cited 2009 Sep 1].
- Available from: http://www. ninds.nih.gov/disorders/chiari/.
- Aitken LA, Lindan CE, Sidney S, Gupta N, Barkovich AJ, Sorel M,
- Wu YW. Chiari type I malformation in a pediatric population. Pediatr
- Neurol 2009;40:449–54.