Öz

Objective: Chiari 1 malformation is a congenital anomaly characterized by downward displacement of the cerebellar tonsils through the foramen magnum. Surgical decision-making in Chiari 1 largely depends on clinical symptoms and imaging findings, particularly the presence of headache and syringohydromyelia. This study aimed to evaluate the radiological characteristics and postoperative imaging changes in pediatric patients with Chiari 1 and Chiari 1.5 malformations.

Material and Methods: This retrospective study included 101 pediatric patients (age range; 1–18 years) diagnosed with Chiari 1 or Chiari 1.5 based on brain and cervical spine MRI findings between November 2022 and April 2025. Clinical and radiological data, including tonsillar descent, syringomyelia, craniovertebral junction anomalies, and basal angle measurements were analyzed. Twenty-one patients underwent posterior fossa decompression and postoperative MRIs were evaluated at 3 and 6 months. Statistical analyses were performed using chi-square, Mann–Whitney U, Wilcoxon signed-rank, and McNemar tests, with p <0.050 considered significant.

Results: Among the 101 patients, 52 (51%) were female, and 49 (49%) were male (mean age; 11.1±4.9 years). Headache was significantly more frequent in operated patients (66.7% vs. 32.5%, p=0.014). Syringomyelia was also more common in the surgical group (33.3% vs. 3.8%, p <0.001), and tonsillar descent was greater (14.3±5.3 mm vs. 9.5±3.6 mm, p<0.001). No significant differences were found between the groups regarding age, sex, basal angle, or foramen magnum diameter. Postoperative follow-up revealed regression of syrinx dimensions and clinical improvement in all operated patients.

Conclusion: Headache, syrinx formation, and greater tonsillar descent are key radiological and clinical predictors of surgical intervention in pediatric Chiari 1. While craniovertebral junction anomalies and hydrocephalus may coexist, they appear less predictive of surgical necessity. Posterior fossa decompression remains a safe and effective treatment in symptomatic pediatric patients, leading to both clinical and radiological improvement.

Anahtar Kelimeler: Chiari 1 malformation, craniovertebral junction, pediatric MRI, posterior fossa decompression, syringomyelia

Kaynakça

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Nasıl atıf yapılır

1.
Yılmaz Ş, Uçan B, Bulut H, Emrahoğlu ME, Demirbilek Özdemir ZZ. Radiological evaluation of Chiari 1 malformation: Diagnostic findings and postsurgical imaging. Turk J Pediatr Dis. 2026;20(2):122-128. https://doi.org/10.12956/TJPD.2025.1271