Syringomyelia Associated with Chiari 1 Malformation in Adults: Positive Outcome Predictors after Posterior Fossa Decompression with Duraplasty

Palma Ciaramitaro; Giuseppe Migliaretti; Marilena Ferraris; Andrea Garnero; Giovanni Morana; Paolo Carucci; Ilaria Stura; Fulvio Massaro; Diego Garbossa

doi:10.3390/jcm12083019

Syringomyelia Associated with Chiari 1 Malformation in Adults: Positive Outcome Predictors after Posterior Fossa Decompression with Duraplasty

J Clin Med. 2023 Apr 21;12(8):3019. doi: 10.3390/jcm12083019.

Authors

Palma Ciaramitaro^{1

2}, Giuseppe Migliaretti³, Marilena Ferraris⁴, Andrea Garnero⁴, Giovanni Morana^{1

4}, Paolo Carucci^{1

2}, Ilaria Stura¹, Fulvio Massaro^{1

5}, Diego Garbossa^{1

5}

Affiliations

¹ Neuroscience Department, University of Torino, 10126 Torino, Italy.
² CRESSC, AOU Città della Salute e della Scienza di Torino, 10126 Torino, Italy.
³ Department of Public Health and Paediatric Sciences, University of Torino, 10126 Torino, Italy.
⁴ Diagnostic Imaging Department, AOU Citta' della Salute e della Scienza di Torino, 10126 Torino, Italy.
⁵ Neurosurgery Unit, AOU Città della Salute e della Scienza di Torino, 10126 Torino, Italy.

Abstract

Background: Syringomyelia (Syr) in patients with Chiari 1 malformation (CM1) may be attributable to abnormal dynamics of cerebrospinal fluid (CSF) in the upper cervical segment; fourth ventricle enlargement has been reported in association with a worse clinical and radiological presentation, independently of the posterior fossa volume. In this study, we analyzed presurgery hydrodynamic markers to evaluate if their changes could be associated with clinical and radiological improvement after posterior fossa decompression and duraplasty (PFDD). As a primary endpoint, we aimed to correlate improvement in the fourth ventricle area with positive clinical outcomes.

Methods: In total, in this study, we enrolled 36 consecutive adults with Syr and CM1 who were followed by a multidisciplinary team. All the patients were prospectively evaluated with clinical scales and neuroimaging, including CSF flow, the fourth ventricle area, and the Vaquero Index by using a phase-contrast MRI before (T0) and after surgical treatment (T1-Tlast, with a range of 12-108 months). The CSF flow at the craniocervical junction (CCJ), the fourth ventricle area, and the Vaquero Index changes were statistically analyzed and compared to the clinical and quality of life improvement after surgery. The good outcome prediction ability of presurgical radiological variables was tested.

Results: Surgery was associated with positive clinical and radiological outcomes in more than 90% of cases. The fourth ventricle area significantly reduced after surgery (T0-Tlast, p = 0.0093), but no significant associations with clinical improvement were found. The presurgical presence of CSF flow at the CCJ was able to predict a good outcome (AUC = 0.68, 95% CI 0.50-0.87 and LH+ = 2.1, IC 95% 1.16-3.07) and was also significantly associated with post-surgical pain relief (rho = 0.61 and p = 0.0144).

Conclusions: Presurgery CSF flow at the CCJ is proposed as a radiological marker with the ability to predict a positive outcome after PFDD in adults with syringomyelia and CM1. Measurements of the fourth ventricle area could be useful additional information for evaluating surgical long-term follow-up; further experience on larger cohorts is required to better define the prognostic yield of this radiological parameter.

Keywords: Chiari 1 malformation; PC-MRI; PFDD; adults; outcome; surgery; syringomyelia.

Grants and funding

This research received no external funding.