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  • Morphometric and Volumetric Comparison of Symptomatic and Asymptomatic Chiari Malformation Type I

    Final Number:

    Siri Sahib S. Khalsa MD; Ndi Geh MD; Bryn A Martin PhD; Philip A Allen PhD; Jennifer Strahle MD; Francis Loth PhD; Desale Habtzghi PhD; Aintzane Urbizu PhD; Hugh Garton MD; Karin M. Muraszko MD, FACS; Cormac O. Maher MD, FACS, FAAP

    Study Design:

    Subject Category:

    Meeting: Congress of Neurological Surgeons 2017 Annual Meeting

    Introduction: Chiari malformation type I (CMI) is typically defined by a cerebellar tonsil position 5 mm or more below foramen magnum. Low cerebellar tonsil position is a frequent incidental finding, even in asymptomatic individuals. Non-specific symptoms such as headache and neck pain are common in those with low tonsil position and in those with normal tonsil position, leading to uncertainty regarding appropriate management for many patients with low tonsil position and non-specific symptoms. Since cerebellar tonsil position is not strictly correlated with typical CMI symptoms, we sought to determine if other 2D morphometric or 3D volumetric measurements on MRI could distinguish asymptomatic from symptomatic CMI patients.

    Methods: We retrospectively analyzed 102 pediatric patients from the University of Michigan clinical CMI database. All patients in this database have cerebellar tonsil position at least 5 mm below foramen magnum. Fifty-one symptomatic and 51 asymptomatic patients were matched for age at diagnosis, sex, tonsil position, and tonsil morphology. Five 2D anatomic MRI measurements and four 3D volumetric measurements of posterior fossa and CSF sub-volumes on MRI were measured.

    Results: There were no significant differences observed between symptomatic and asymptomatic CMI patients related to basilar impression (-5.9 mm vs. -7.0 mm; p=0.026), tentorium length (50.3 mm vs. 51.0 mm; p=0.537), supraoccipital length (39.4 mm vs. 42.6 mm; p=0.055), clivus-tentorium distance (52.0 mm vs. 52.1 mm; p=0.964), clivus-torcula distance (81.5 mm vs. 83.3 mm; p=0.257), total posterior fossa volume (PFV; 183.4 mL vs. 190.6 mL; p=0.250), caudal PFV (152.5 mL vs. 159.8 mL; p=0.256), fourth ventricle volume to caudal PFV ratio (0.0140 vs. 0.0136; p=0.649), or CSF volume to caudal PFV ratio (0.071 vs. 0.061; p=0.138).

    Conclusions: We did not identify any 2D or 3D measurements that could reliably distinguish pediatric patients with symptoms attributable to CMI from those with asymptomatic CMI.

    Patient Care: It is important to correctly diagnose symptomatic CMI in order to avoid unnecessary and ineffective surgery as well as to avoid delayed diagnosis and treatment in truly symptomatic cases. This investigation is a step toward developing a method of identifying true symptomatic CMI among the many patients with low tonsil position and non-specific symptoms.

    Learning Objectives: By the conclusion of this session, participants should: 1) Appreciate the uncertainty regarding appropriate management for many patients with low tonsil position and non-specific symptoms. 2) Realize the limitations of MRI measurements in distinguishing pediatric patients with symptoms attributable to Chiari I (CMI) from those with asymptomatic CMI. 3) Consider investigating new methods to reliably distinguish symptomatic from asymptomatic pediatric CMI.

    References: 1. Aboulezz AO, Sartor K, Geyer CA, Gado MH: Position of cerebellar tonsils in the normal population and in patients with Chiari malformation: a quantitative approach with MR imaging. J Comput Assist Tomogr 9:1033-1036, 1985 2. Aitken LA, Lindan CE, Sidney S, Gupta N, Barkovich AJ, Sorel M, et al: Chiari type I malformation in a pediatric population. Pediatr Neurol 40:449-454, 2009 3. Alperin N, Sivaramakrishnan A, Lichtor T: Magnetic resonance imaging-based measurements of cerebrospinal fluid and blood flow as indicators of intracranial compliance in patients with Chiari malformation. J Neurosurg 103:46-52, 2005 4. Arora P, Behari S, Banerji D, Chhabra DK, Jain VK: Factors influencing the outcome in symptomatic Chiari I malformation. Neurol India 52:470-474, 2004 5. Aydin S, Hanimoglu H, Tanriverdi T, Yentur E, Kaynar MY: Chiari type I malformations in adults: a morphometric analysis of the posterior cranial fossa. Surg Neurol 64:237-241, 2005 6. Barkovich AJ, Wippold FJ, Sherman JL, Citrin CM: Significance of cerebellar tonsillar position on MR. AJNR Am J Neuroradiol 7:795-799, 1986 7. Benglis D, Jr., 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 7:375-379, 2011 8. Bunck AC, Kroeger JR, Juettner A, Brentrup A, Fiedler B, Crelier GR, et al: Magnetic resonance 4D flow analysis of cerebrospinal fluid dynamics in Chiari I malformation with and without syringomyelia. Eur Radiol 22:1860-1870, 2012 9. Chern JJ, Gordon AJ, Mortazavi MM, Tubbs RS, Oakes WJ: Pediatric Chiari malformation Type 0: a 12-year institutional experience. J Neurosurg Pediatr 8:1-5, 2011 10. Dagtekin A, Avci E, Kara E, Uzmansel D, Dagtekin O, Koseoglu A, et al: Posterior cranial fossa morphometry in symptomatic adult Chiari I malformation patients: comparative clinical and anatomical study. Clin Neurol Neurosurg 113:399-403, 2011 11. Dones J, De Jesus O, Colen CB, Toledo MM, Delgado M: Clinical outcomes in patients with Chiari I malformation: a review of 27 cases. Surg Neurol 60:142-147, 2003 12. Elster AD, Chen MY: Chiari I malformations: clinical and radiologic reappraisal. Radiology 183:347-353, 1992 13. Furtado SV, Reddy K, Hegde AS: Posterior fossa morphometry in symptomatic pediatric and adult Chiari I malformation. J Clin Neurosci 16:1449-1454, 2009 14. Furuya K, Sano K, Segawa H, Ide K, Yoneyama H: Symptomatic tonsillar ectopia. J Neurol Neurosurg Psychiatry 64:221-226, 1998 15. Genitori L, Peretta P, Nurisso C, Macinante L, Mussa F: Chiari type I anomalies in children and adolescents: minimally invasive management in a series of 53 cases. Childs Nerv Syst 16:707-718, 2000 16. Hofkes SK, Iskandar BJ, Turski PA, Gentry LR, McCue JB, Haughton VM: Differentiation between symptomatic Chiari I malformation and asymptomatic tonsilar ectopia by using cerebrospinal fluid flow imaging: initial estimate of imaging accuracy. Radiology 245:532-540, 2007 17. Isik N, Elmaci I, Silav G, Celik M, Kalelioglu M: Chiari malformation type III and results of surgery: a clinical study: report of eight surgically treated cases and review of the literature. Pediatr Neurosurg 45:19-28, 2009 18. Karagoz F, Izgi N, Kapijcijoglu Sencer S: Morphometric measurements of the cranium in patients with Chiari type I malformation and comparison with the normal population. Acta Neurochir 144:165-171, 2002 19. Krueger KD, Haughton VM, Hetzel S: Peak CSF velocities in patients with symptomatic and asymptomatic Chiari I malformation. AJNR Am J Neuroradiol 31:1837-1841, 2010 20. Martin BA, Kalata W, Shaffer N, Fischer P, Luciano M, Loth F: Hydrodynamic and longitudinal impedance analysis of cerebrospinal fluid dynamics at the craniovertebral junction in type I Chiari malformation. PLoS One 8:e75335, 2013 21. Martin BA, Shaffer N, Lowenkamp M, Loth F, Tew J, Luciano M: Clinical importance of neural tissue deformation in type I Chiari malformation. Proceedings of the American Society of Pediatric Neurosurgeons Abstract, 2013 22. Meadows J, Kraut M, Guarnieri M, Haroun RI, Carson BS: Asymptomatic Chiari Type I malformations identified on magnetic resonance imaging. J Neurosurg 92:920-926, 2000 23. Morris Z, Whiteley WN, Longstreth WT, Jr., Weber F, Lee YC, Tsushima Y, et al: Incidental findings on brain magnetic resonance imaging: systematic review and meta-analysis. BMJ 339:b3016, 2009 24. Nishikawa M, Sakamoto H, Hakuba A, Nakanishi N, Inoue Y: Pathogenesis of Chiari malformation: a morphometric study of the posterior cranial fossa. J Neurosurg 86:40-47, 1997 25. 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. Clinical article. J Neurosurg 111:1046-1052, 2009 26. 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 2:179-187, 2008 27. Pomeraniec IJ, Ksendzovsky A, Awad AJ, Fezeu F, Jane JA, Jr.: Natural and surgical history of Chiari malformation Type I in the pediatric population. J Neurosurg Pediatr 17:343-352, 2016 28. Schneider CA, Rasband WS, Eliceiri KW: NIH Image to ImageJ: 25 years of image analysis. Nat Methods 9:671-675, 2012 29. Sekula RF, Jr., Jannetta PJ, Casey KF, Marchan EM, Sekula LK, McCrady CS: Dimensions of the posterior fossa in patients symptomatic for Chiari I malformation but without cerebellar tonsillar descent. Cerebrospinal Fluid Res 2:11, 2005 30. Sgouros S, Kountouri M, Natarajan K: Posterior fossa volume in children with Chiari malformation Type I. J Neurosurg 105:101-106, 2006 31. Shehu B, Ismail N, Mahmud M, Hassan I: Chiari I malformation: a missed diagnosis. Ann Afr Med 5:206-208, 2006 32. Smith BW, Strahle J, Bapuraj JR, Muraszko KM, Garton HJ, Maher CO: Distribution of cerebellar tonsil position: implications for understanding Chiari malformation. J Neurosurg 119:812-819, 2013 33. Strahle J, Muraszko KM, Kapurch J, Bapuraj JR, Garton HJ, Maher CO: Chiari malformation Type I and syrinx in children undergoing magnetic resonance imaging. J Neurosurg Pediatr 8:205-213, 2011 34. Trigylidas T, Baronia B, Vassilyadi M, Ventureyra EC: Posterior fossa dimension and volume estimates in pediatric patients with Chiari I malformations. Childs Nerv Syst 24:329-336, 2008 35. Tubbs RS, Elton S, Grabb P, Dockery SE, Bartolucci AA, Oakes WJ: Analysis of the posterior fossa in children with the Chiari 0 malformation. Neurosurgery 48:1050-1054; discussion 1054-1055, 2001 36. Urbizu A, Poca MA, Vidal X, Rovira A, Sahuquillo J, Macaya A: MRI-based morphometric analysis of posterior cranial fossa in the diagnosis of chiari malformation type I. J Neuroimaging 24:250-256, 2014 37. Ventureyra EC, Aziz HA, Vassilyadi M: The role of cine flow MRI in children with Chiari I malformation. Childs Nerv Syst 19:109-113, 2003 38. Vernooij MW, Ikram MA, Tanghe HL, Vincent AJ, Hofman A, Krestin GP, et al: Incidental findings on brain MRI in the general population. N Engl J Med 357:1821-1828, 2007 39. 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 16:159-166, 2015 40. Wu YW, Chin CT, Chan KM, Barkovich AJ, Ferriero DM: Pediatric Chiari I malformations: do clinical and radiologic features correlate? Neurology 53:1271-1276, 1999 41. Yiallourou TI, Kroger JR, Stergiopulos N, Maintz D, Martin BA, Bunck AC: Comparison of 4D phase-contrast MRI flow measurements to computational fluid dynamics simulations of cerebrospinal fluid motion in the cervical spine. PLoS One 7:e52284, 2012

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