TO THE EDITOR: We read with interest the article by Akbari et al.1 (Akbari SHA, Yahanda AT, Ackerman LL, et al. Complications and outcomes of posterior fossa decompression with duraplasty versus without duraplasty for pediatric patients with Chiari malformation type I and syringomyelia: a study from the Park-Reeves Syringomyelia Research Consortium. J Neurosurg Pediatr. 2022;30[1]:39-51), which reports better outcomes but more postoperative complications with posterior fossa decompression with duraplasty compared to posterior fossa decompression. As the first large-scale, multi-institutional study of pediatric patients undergoing these procedures, although the article did not have surprising results, it has important implications for the choice of surgical procedures to manage Chiari malformation type I (CM1) and syringomyelia (SM) in our clinical practice. In addition, we found some new insights worth sharing with the readers from the study’s analysis of prognostic assessment.
As we can see from the results of the outcome evaluation of this study, the rate resolution or improvement of symptoms (e.g., headache and back pain) after surgery was more than 80%, but the results for the associated signs were not satisfactory. Why is there a worse recovery of signs after CM1-SM surgery? A careful observation of the clinical outcomes shows that these signs are mainly associated with SM. These signs are usually due to prolonged and continuous compression of the spinal cord and brainstem by SM, and therefore they are difficult to resolve after surgery even after the compression has been removed.2 We can also observe in previous studies that the prognosis of patients with CM1-SM is significantly worse than in patients with CM1 alone. Therefore, the latest edition of the international consensus document on diagnosis and treatment of CM1 in children includes progressive spinal cord cavities as an indication for surgery.3
In addition, the analysis of prognostic risk factors in this study showed that postoperative complications were not associated with age in patients. However, another retrospective study, also from the Park-Reeves Syringomyelia Research database, found that younger patients were associated with postoperative syrinx improvement.4 Therefore, we speculate whether the corresponding signs and symptoms are more likely to resolve postoperatively because of the shorter duration of spinal cord compression by the syrinx in younger patients with CM1-SM. If this is indeed the case, it will have a significant impact on the choice for the timing of surgery for patients with CM1-SM. Of course, it is necessary to validate this by further studying the natural history of CM1-SM and the relationship between the disease duration and prognosis.
Disclosures
The authors report no conflict of interest.
References
- 1↑
Akbari SHA, Yahanda AT, Ackerman LL, et al. Complications and outcomes of posterior fossa decompression with duraplasty versus without duraplasty for pediatric patients with Chiari malformation type I and syringomyelia: a study from the Park-Reeves Syringomyelia Research Consortium. J Neurosurg Pediatr. 2022;30(1):39–51.
- 2↑
Thakar S, Sivaraju L, Jacob KS, et al. A points-based algorithm for prognosticating clinical outcome of Chiari malformation Type I with syringomyelia: results from a predictive model analysis of 82 surgically managed adult patients. J Neurosurg Spine. 2018;28(1):23–32.
- 3↑
Ciaramitaro P, Massimi L, Bertuccio A, et al. Diagnosis and treatment of Chiari malformation and syringomyelia in adults: international consensus document. Neurol Sci. 2022;43(2):1327–1342.
- 4↑
Hale AT, Adelson PD, Albert GW, et al. Factors associated with syrinx size in pediatric patients treated for Chiari malformation type I and syringomyelia: a study from the Park-Reeves Syringomyelia Research Consortium. J Neurosurg Pediatr. 2020;25(6):629–639.
