Decompression for Chiari type I-malformation (with or without syringomyelia) by extreme lateral foramen magnum opening and expansile duraplasty with arachnoid preservation: comparison with other technical modalities (Literature review)

  • M. Sindou
  • E. Gimbert


Posterior craniocervical decompression is the procedure most currently used for treating Chiari I malformation (alone or in association with syringomyelia in the absence of hydrocephalus). We reviewed the various technical modalities reported in the literature. We present a personal series of 44 patients harboring Chiari type I malformation (CM-I) operated with a suboccipital craniectomy and a C1 (or C1/C2) laminectomy, plus an extreme lateral Foramen Magnum opening, a “Y” shaped dural incision with preservation of the arachnoid membrane, and an expansile duraplasty employing autogenous periosteum. Outcomes were analyzed with follow-up ranging from 1 to 10 years (4 years on average).

The presented technique was compared with the other surgical modalities reported in the literature. This comparative study shows that this type of craniocervical decompression achieved the best results with minimal complications and side-effects. Syringomyelia associated with CM-I must be treated by craniocervical decompression alone. Shunting no longer appears to be an appropriate method of treatment for syringomyelia.


Chiari type I malformation foramen magnum decompression syringomyelia cerebrospinal flow posterior fossa surgery 


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. 1.
    Aghakhani N, Parker F, Tadie M (1999) Syringomyelia and Chiari abnormality in the adult. Analysis of the results of a cooperative series of 285 cases. Neurochirurgie 45 Suppl 1: 23–36PubMedGoogle Scholar
  2. 2.
    Alperin N, et al. (2001) Analysis of magnetic resonance imaging-based blood and cerebrospinal fluid flow measurements in patients with Chiari I malformation: a system approach. Neurosurg Focus 11: E6CrossRefPubMedGoogle Scholar
  3. 3.
    Alzate JC, Kothbauer KF, Jallo GI, Epstein FJ (2001) Treatment of Chiari I malformation in patients with and without syringomyelia: a consecutive series of 66 cases. Neurosurg Focus 11: E3CrossRefPubMedGoogle Scholar
  4. 4.
    Batzdorf U (2000) Microsurgery of syringomyelia and syringomyelia cord syndrome. In: Schmidek HH, Sweet WH (eds) Operative neurosurgical techniques: indication, methods and results. WB Saunders Company, Philadelphia, pp 1946–54Google Scholar
  5. 5.
    Bejjani GK (2001) Definition of the adult Chiari malformation: a brief historical overview. Neurosurg Focus 11: E1CrossRefPubMedGoogle Scholar
  6. 6.
    Bindal AK, Dunsker SB, Tew JM Jr (1995) Chiari I malformation: classification and management. Neurosurgery 37: 1069–74CrossRefPubMedGoogle Scholar
  7. 7.
    Blagodatsky MD, Larionov SN, Alexandrov YA, Velm AI (1999) Surgical treatment of Chiari I malformation with or without syringomyelia. Acta Neurochir (Wien) 141: 963–68CrossRefGoogle Scholar
  8. 8.
    Chang HS, Nakagawa H (2003) Hypothesis on the pathophysiology of syringomyelia based on simulation of cerebrospinal fluid dynamics. J Neurol Neurosurg Psychiatry 74: 344–47CrossRefPubMedGoogle Scholar
  9. 9.
    Chiari H (1891) Üeber Veränderungen des Kleinhirns infolge von Hydrocephalie des Grosshirns. Dtsch Med Wochenschr 17: 1172–75CrossRefGoogle Scholar
  10. 10.
    Chopra JS, Sawhney IM, Kak VK, Khosla VK (1988) Craniovertebral anomalies: a study of 82 cases. Br J Neurosurg 2: 455–64CrossRefPubMedGoogle Scholar
  11. 11.
    Cristante L, Westphal M, Herrmann HD (1994) Cranio-cervical decompression for Chiari I malformation. A retrospective evaluation of functional outcome with particular attention to the motor deficits. Acta Neurochir (Wien) 130: 94–100CrossRefGoogle Scholar
  12. 12.
    Dones J, De Jesus O, Colen CB, Toledo MM, Delgado M (2003) Clinical outcomes in patients with Chiari I malformation: a review of 27 cases. Surg Neurol 60: 142–47; discussion 147–48CrossRefPubMedGoogle Scholar
  13. 13.
    Ellenbogen RG, Armonda RA, Shaw DW, Winn HR (2000) Toward a rational treatment of Chiari I malformation and syringomyelia. Neurosurg Focus 8: E6CrossRefPubMedGoogle Scholar
  14. 14.
    Ellenbogen RG, Zeidman S (2000) Craniovertebral decompression for Chiari Malformation. In: Kaye A, Black P (eds) Operative neurosurgery. Churchill Livingston, London, pp 1725–41Google Scholar
  15. 15.
    Elster AD, Chen MY (1992) Chiari I malformations: clinical and radiologic reappraisal. Radiology 183: 347–53PubMedGoogle Scholar
  16. 16.
    Ergün R, et al. (2000) Surgical management of syringomyelia-Chiari complex. Eur Spine J 9: 553–57CrossRefPubMedGoogle Scholar
  17. 17.
    Fisher E (1995) Posterior fossa decompression for Chiari I deformity, including resection of the cerebellar tonsils. Childs Nerv Syst 11: 625–29CrossRefGoogle Scholar
  18. 18.
    Fujii K, Natori Y, Nakagaki H, Fukui M (1991) Management of syringomyelia associated with Chiari malformation: comparative study of syrinx size and symptoms by magnetic resonance imaging. Surg Neurol 36: 281–85CrossRefPubMedGoogle Scholar
  19. 19.
    Gambardella G, Caruso G, Caffo M, Germano A, La Rosa G, Tomasello F (1998) Transverse microincisions of the outer layer of the dura mater combined with foramen magnum decompression as treatment for syringomyelia with Chiari I malformation. Acta Neurochir (Wien) 140: 134–39CrossRefGoogle Scholar
  20. 20.
    Goel A, Bhatjiwale M, Desai K (1998) Basilar invagination: a study based on 190 surgically treated patients. J Neurosurg 88: 962–68CrossRefPubMedGoogle Scholar
  21. 21.
    Guyotat J, Bret P, Journneau E, Ricci AC, Lapras C (1998) Syringomyelia associated with type I Chiari malformation. A 21-year retrospective study on 75 cases treated by foramen magnum decompresion with a special emphasis on the value of tonsils resection. Acta Neurochir (Wien) 140: 745–54CrossRefGoogle Scholar
  22. 22.
    Heiss JD, et al. (1999) Elucidating the pathophysiology of syringomyelia. J Neurosurg 91: 553–62CrossRefPubMedGoogle Scholar
  23. 23.
    Hida K, Iwasaki Y (2001) Syringosubarachnoid shunt for syringomyelia associated with Chiari I malformation. Neurosurg Focus 11: E7CrossRefPubMedGoogle Scholar
  24. 24.
    Hida K, Iwasaki Y, Koyanagi I, Sawamura Y, Abe H (1995) Surgical indication and results of foramen magnum decompression versus syringosubarachnoid shunting for syringomyelia associated with Chiari I malformation. Neurosurgery 37: 673–78; discussion 678–79CrossRefPubMedGoogle Scholar
  25. 25.
    Holly LT, Batzdorf U (2001) Management of cerebellar ptosis following craniovertebral decompression for Chiari I malformation. J Neurosurg 94: 21–26CrossRefPubMedGoogle Scholar
  26. 26.
    Isu T, Sasaki H, Takamura H, Kobayashi N (1993) Foramen magnum decompression with removal of the outer layer of the dura as treament for syringomyelia occurring with Chiari i malformation. Neurosurgery 33: 844–49; discussion 849–50CrossRefPubMedGoogle Scholar
  27. 27.
    James HE, Brant A (2002) Treatment of the Chiari malformation with bone decompression without durotomy in children and young adults. Childs Nerv Syst 18: 202–06CrossRefPubMedGoogle Scholar
  28. 28.
    Klekamp J, Batzdorf U, Samii M, Bothe HW (1996) The surgical treatment of Chiari I malformation. Acta Neurochir (Wien) 138: 788–801CrossRefGoogle Scholar
  29. 29.
    Lay CM (2002) Low cerebrospinal fluid pressure headache. Curr Treat Options Neurol 4: 357–63CrossRefPubMedGoogle Scholar
  30. 30.
    Marcelis J, Silberstein SD (1990) Spontaneous low cerebrospinal fluid pressure headache. Headache 30: 192–96CrossRefPubMedGoogle Scholar
  31. 31.
    Marin-Padilla M, Marin-Padilla TM (1981) Morphogenesis of experimentally induced Arnold-Chiari malformation. J Neurol Sci 50: 29–55CrossRefPubMedGoogle Scholar
  32. 32.
    McGirt MJ, Nimjee SM, Floyd J, Bulsara KR, George TM (2005) Correlation of cerebrospinal fluid flow dynamics and headache in Chiari I malformation. Neurosurgery 56: 716–21; discussion 716–21CrossRefPubMedGoogle Scholar
  33. 33.
    McGirt MJ, Nimjee SM, Fuchs HE, George TM (2006) Relationship of cine phase-contrast magnetic resonance imaging with outcome after decompression for Chiari I malformations. Neurosurgery 59: 140–146; discussion 140–46CrossRefPubMedGoogle Scholar
  34. 34.
    Meadows J, Kraut M, Guarnieri M, Haroun RI, Carson BS (2000) Asymptomatic Chiari type I malformations identified on magnetic resonance imaging. J Neurosurg 92: 920–26CrossRefPubMedGoogle Scholar
  35. 35.
    Menezes AH (1995) Primary craniovertebral anomalies and the hindbrain herniation syndrome (Chiari I): data base analysis. Pediatr Neurosurg 23: 260–69CrossRefPubMedGoogle Scholar
  36. 36.
    Milhorat TH, Bolognese PA (2003) Tailored operative technique for Chiari type I malformation using intraoperative color Doppler ultrasonography. Neurosurgery 53: 899–905; discussion 905–896CrossRefPubMedGoogle Scholar
  37. 37.
    Milhorat TH, et al. (1999) Chiari I malformation redefined: clinical and radiographic findings for 364 symptomatic patients. Neurosurgery 44: 1005–17CrossRefPubMedGoogle Scholar
  38. 38.
    Mokri B (1999) Spontaneous cerebrospinal fluid leaks: from intracranial hypotension to cerebrospinal fluid hypovolemia-evolution of a concept. Mayo Clin Proc 74: 1113–23CrossRefPubMedGoogle Scholar
  39. 39.
    Mokri B, Atkinson JL, Dodick DW, Miller GM, Piepgras DG (1999) Absent pachymeningeal gadolinium enhancement on cranial MRI despite symptomatic CSF leak. Neurology 53: 402–04PubMedGoogle Scholar
  40. 40.
    Munshi I, Frim D, Stine-Reyes R, Weir BK, Hekmatpanah J, Brown F (2000) Effects of posterior fossa decompression with and without duraplasty on Chiari malformation-associated hydromyelia. Neurosurgery 46: 1384–89; discussion 1389–90CrossRefPubMedGoogle Scholar
  41. 41.
    Navarro R, Olavarria G, Seshadri R, Gonzales-Portillo G, McLone DG, Tomita T (2004) Surgical results of posterior fossa decompression for patients with Chiari I malformation. Childs Nerv Syst 20: 349–56CrossRefPubMedGoogle Scholar
  42. 42.
    Nishikawa M, Sakamoto H, Hakuba A, Nakanishi N, Inoue Y (1997) Pathogenesis of Chiari malformation: a morphometric study of the posterior cranial fossa. J Neurosurg 86: 40–47CrossRefPubMedGoogle Scholar
  43. 43.
    Nishizawa S, Yokoyama T, Yokota N, Tokuyama T, Ohta S (2001) Incidentally identified syringomyelia associated with Chiari I malformations: is early interventional surgery necessary? Neurosurgery 49: 637–40; discussion 640–31CrossRefPubMedGoogle Scholar
  44. 44.
    Oldfield EH, Muraszko K, Shawker TH, Patronas NJ (1994) Pathophysiology of syringomyelia associated with Chiari I malformation of the cerebellar tonsils. Implications for diagnosis and treatment. J Neurosurg 80: 3–15CrossRefPubMedGoogle Scholar
  45. 45.
    Paldino M, Mogilner AY, Tenner MS (2003) Intracranial hypotension syndrome: a comprehensive review. Neurosurg Focus 15: ECP2CrossRefPubMedGoogle Scholar
  46. 46.
    Paul KS, Lye RH, Strang FA, Dutton J (1983) Arnold-Chiari malformation. Review of 71 cases. J Neurosurg 58: 183–87CrossRefPubMedGoogle Scholar
  47. 47.
    Pillay PK, Awad IA, Little JR, Hahn JF (1991) Symptomatic Chiari malformation in adults: a new classification based on magnetic resonance imaging with clinical and prognostic significance. Neurosurgery 28: 639–45CrossRefPubMedGoogle Scholar
  48. 48.
    Raftopoulos C, Sanchez A, Matos C, Baleriaux D, Bank WO, Brotchi J (1993) Hydrosyringomyelia-Chiari I complex. Prospective evaluation of a modified foramen magnum decompression procedure: preliminary results. Surg Neurol 39: 163–69CrossRefPubMedGoogle Scholar
  49. 49.
    Raskin NH (1990) Lumbar puncture headache: a review. Headache 30: 197–200CrossRefPubMedGoogle Scholar
  50. 50.
    Rhoton A (2000) Management of syringomyelia. In: Kaye A, Black P (eds) Operative neurosurgery. Churchill Livingston, London, pp 1743–54Google Scholar
  51. 51.
    Rhoton A (2000) Microsurgery of syringomyelia and the syringomyelia-Chiari complex. In: Schmidek HH, Sweet WH (eds) Operative neurosurgical techniques: indications, methods and results. WB Saunders Company, Philadelphia, pp 1955–69Google Scholar
  52. 52.
    Sahuquillo J, Rubio E, Poca MA, Rovira A, Rodriguez-Baeza A, Cervera C (1994), Posterior fossa reconstruction: a surgical technique for the treatment of Chiari I malformation and Chiari I/syringomyelia complex-preliminary results and magnetic resonance imaging quantitative assessment of hindbrain migration. Neurosurgery 35: 874–84; discussion 884–75CrossRefPubMedGoogle Scholar
  53. 53.
    Sakamoto H, et al. (1999) Expansive suboccipital cranioplasty for the treatment of syringomyelia associated with Chiari malformation. Acta Neurochir (Wien) 141: 949–960; discussion 960–941CrossRefGoogle Scholar
  54. 54.
    Sakas DE, et al. (2005) Chiari malformation: CSF flow dynamics in the craniocervical junction and syrinx. Acta Neurochir (Wien) 147: 1223–33CrossRefGoogle Scholar
  55. 55.
    Sansur CA, Heiss JD, DeVroom HL, Eskioglu E, Ennis R, Oldfield EH (2003) Pathophysiology of headache associated with cough in patients with Chiari I malformation. J Neurosurg 98: 453–58CrossRefPubMedGoogle Scholar
  56. 56.
    Schady W, Metcalfe RA, Butler P (1987) The incidence of craniocervical bony anomalies in the adult Chiari malformation. J Neurol Sci 82: 193–203CrossRefPubMedGoogle Scholar
  57. 57.
    Schijman E (2004) History, anatomic forms, and pathogenesis of Chiari I malformations. Childs Nerv Syst 20: 323–28CrossRefPubMedGoogle Scholar
  58. 58.
    Scott RM (2004) Tallored operative technique for Chiari type I malformation using intraoperative color Doppler ultrasonography. Neurosurgery 55: 1008; author reply 1008CrossRefPubMedGoogle Scholar
  59. 59.
    Sgouros S, Kountouri M, Natarajan K (2006) Posterior fossa volume in children with Chiari malformation type I. J Neurosurg 105: 101–06PubMedGoogle Scholar
  60. 60.
    Sindou M, Chavez-Machuca J, Hashish H (2002) Cranio-cervical decompression for Chiari type I-malformation, adding extreme lateral foramen magnum opening and expansile duroplasty with arachnoid preservation. Technique and long-term functional results in 44 consecutive adult cases — comparison with literature data. Acta Neurochir (Wien) 144: 1005–19Google Scholar
  61. 61.
    Sivaramakrishnan A, Alperin N, Surapaneni S, Lichtor T (2004) Evaluating the effect of decompression surgery on cerebrospinal fluid flow and intracranial compliance in patients with chiari malformation with magnetic resonance imaging flow studies. Neurosurgery 55: 1344–50; discussion 1350–1341CrossRefPubMedGoogle Scholar
  62. 62.
    Stovner LJ, Bergan U, Nilsen G, Sjaastad O (1993) Posterior cranial fossa dimensions in the Chiari I malformation: relation to pathogenesis and clinical presentation. Neuroradiology 35: 113–18CrossRefPubMedGoogle Scholar
  63. 63.
    Takayasu M, Takagi T, Hara M, Anzai M (2004) A simple technique for expansive suboccipital cranioplasty following foramen magnum decompression for the treatment of syringomyelia associated with Chiari I malformation. Neurosurg Rev 27: 173–77CrossRefPubMedGoogle Scholar
  64. 64.
    Tognetti F, Calbucci F (1993) Syringomyelia: syringo-subarachnoid shunt versus posterior fossa decompression. Acta Neurochir (Wien) 123: 196–97Google Scholar
  65. 65.
    Tubbs RS, Iskandar BJ, Bartolucci AA, Oakes WJ (2004) A critical analysis of the Chiari 1.5 malformation. J Neurosurg 101: 179–83CrossRefPubMedGoogle Scholar
  66. 66.
    Tubbs RS, McGirt MJ, Oakes WJ (2003) Surgical experience in 130 pediatric patients with Chiari I malformations. J Neurosurg 99: 291–96CrossRefPubMedGoogle Scholar
  67. 67.
    Van Velthoven V, Jost M, Siekmann R, Eggert HR (1993) Surgical strategies and results in syringomyelia. Acta Neurochir (Wien) 123: 199–201Google Scholar
  68. 68.
    Vanaclocha V, Saiz-Sapena N (1997) Duraplasty with freeze-dried cadaveric dura versus occipital pericranium for Chiari type I malformation: comparative study. Acta Neurochir (Wien) 139: 112–19CrossRefGoogle Scholar
  69. 69.
    Vanaclocha V, Saiz-Sapena N, Garcia-Casasola MC (1997) Surgical technique for craniocervical decompression in syringomyelia associated with Chiari type I malformation. Acta Neurochir (Wien) 139: 529–539; discussion 539–40CrossRefGoogle Scholar
  70. 70.
    Vaquero J, Martinez R, Arias A (1990) Syringomyelia-Chiari complex: magnetic resonance imaging and clinical evaluation of surgical treatment. J Neurosurg 73: 64–68CrossRefPubMedGoogle Scholar
  71. 71.
    Vega A, Quintana F, Berciano J (1990) Basichondrocranium anomalies in adult Chiari type I malformation: a morphometric study. J Neurol Sci 99: 137–45CrossRefPubMedGoogle Scholar
  72. 72.
    Versari PP, D’Aliberti G, Talamonti G, Collice M (1993) Foraminal syringomyelia: suggestion for a grading system. Acta Neurochir (Wien) 125: 97–104CrossRefGoogle Scholar
  73. 73.
    Wagshul ME, Chen JJ, Egnor MR, McCormack EJ, Roche PE (2006) Amplitude and phase of cerebrospinal fluid pulsations: experimental studies and review of the literature. J Neurosurg 104: 810–19CrossRefPubMedGoogle Scholar
  74. 74.
    Williams B (1981): Simultaneous cerebral and spinal fluid pressure recordings. 2. Cerebrospinal dissociation with lesions at the foramer magnum. Acta Neurochir (Wien) 59: 123–42CrossRefGoogle Scholar
  75. 75.
    Williams B (1991) Pathogenesis of syringomyelia. In: U B (eds) Syringomyelia. Current concepts in diagnosis and treatment Williams, pp 90Google Scholar
  76. 76.
    Williams B (1993) Surgical treatment of syringobulbia. Neurosurg Clin N Am 4: 553–71PubMedGoogle Scholar
  77. 77.
    Yeh DD, Koch B, Crone KR (2006) Intraoperative ultrasonography used to determine the extent of surgery necessary during posterior fossa decompression in children with Chiari malformation type I. J Neurosurg 105: 26–32CrossRefPubMedGoogle Scholar

Copyright information

© Springer-Verlag/Wien 2009

Authors and Affiliations

  • M. Sindou
    • 1
  • E. Gimbert
    • 1
  1. 1.Department of Neurosurgery, Hôpital Neurologique Pierre WertheimerUniversity of LyonLyonFrance

Personalised recommendations