A rare clinical case of syringomyelia progression in the presence of Chiari I malformation following the surgery

Today, an Arnold-Chiari malformation is defined as a developmental pathology of the craniovertebral junction manifested by a discrepancy between the volume and contents of the posterior cranial fossa, which in turn leads to compression of neurological structures and changes in the cerebrospinal fluid circulation. There are several theories of the correlation between Chiari malformation and syringomyelia, but the exact mechanism of syringomyelia development remains unclear.

This article describes a clinical case of treatment of a child with Chiari I malformation and syringomyelia within the cervical and thoracic segments of the spinal cord; after complete posterior fossa decompression, syringomyelia progressed in the early postoperative period with the development of a severe neurological deficiency. Since there is no standard treatment of such postoperative complications, a decision was made on the expectant management of the patient. From the twentieth day of the postoperative period, the patient showed complete regression of the neurological deficiency and positive MRI dynamics of syringomyelia.

The presented clinical case raises such issues as not only the pathophysiology of syringomyelia progression after complete posterior fossa decompression, but also the determination of patient management tactics in case of a complicated postoperative course of the disease.

The presented clinical case is of interest due to the rarely described aggravation of syringomyelia with enhancing neurological symptoms in the early postoperative period after complete posterior fossa decompression. Our observation suggests that the expectant management of the patient, despite syringomyelia progression with neurological deficiency aggravation after posterior fossa decompression, allowed a favorable long-term outcome of Chiari I malformation.

1. Tubbs RS, Beckman J, Naftel RP, Chern JJ, Wellons JC, Rozzelle CJ, et al. Institutional experience with 500 cases of surgically treated pediatric Chiari malformation Type I. J Neurosurg Pediatr. 2011 Mar;7(3):248–256. https://doi.org/10.3171/2010.12.PEDS10379

2. Langridge B, Phillips E, Choi D. Chiari Malformation Type 1: A Systematic Review of Natural History and Conservative Management. World Neurosurg. 2017 Aug;104:213–219. https://doi.org/10.1016/j.wneu.2017.04.082

3. Oldfield EH. Pathogenesis of Chiari I - Pathophysiology of Syringomyelia: Implications for Therapy: A Summary of 3 Decades of Clinical Research. Neurosurgery. 2017 Sep 1;64(CN_suppl_1):66–77. https://doi.org/10.1093/neuros/nyx377

4. Zuev AA, Kostenko GV. Differentiated approach to surgical treatment of chiari anomaly of type 1 and syringomyelia. Bulletin of the National Medical and Surgical Center named after N. I. Pirogov 2018;13(1):53-57. (In Russ.).

5. Deora H, Behari S, Sardhara J, Singh S, Srivastava AK. Is Cervical Stabilization for All Cases of Chiari-I Malformation an Overkill? Evidence Speaks Louder Than Words! Neurospine. 2019 Jun;16(2):195–206. https://doi.org/10.14245/ns.1938192.096

6. Gil Z, Rao S, Constantini S. Expansion of Chiari I-associated syringomyelia after posterior-fossa decompression. Childs Nerv Syst. 2000 Sep;16(9):555–558. https://doi.org/10.1007/s003810000329

7. Chaouki Khoury. Chiari malformations [Internet]. UpToDate. 2003. Available at: https://www.uptodate.com/contents/ chiari-malformations, Accessed: 03.07.2023.

8. Kular S, Cascella M. Chiari I Malformation. 2022 Feb 5. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing. 2023 Jan.

9. Heiss JD, Patronas N, DeVroom HL, Shawker T, Ennis R, Kammerer W, et al. Elucidating the pathophysiology of syringomyelia. J Neurosurg. 1999 Oct;91(4):553–562. https://doi.org/10.3171/jns.1999.91.4.0553

10. Dzmitry V, Irina T, Hanna V. The Arnold-Chiari Anomaly: A Review of Literature. AJBSR. 2022 Apr 20;16(1):66. https://doi.org/10.34297/AJBSR.2022.16.002193

11. Heiss JD, Suffredini G, Smith R, DeVroom HL, Patronas NJ, Butman JA, et al. Pathophysiology of persistent syringomyelia after decompressive craniocervical surgery. Clinical article. J Neurosurg Spine. 2010 Dec;13(6):729–742. https://doi.org/10.3171/2010.6.SPINE10200