Various manifestation of Chiari I malformation in children and improvement after surgery

Introduction: Chiari I malformation is defined as caudal displacement of the cerebellar tonsils into the foramen magnum. The most commonly associated finding is cervical syringomyelia. The most common presenting symptom is occipital and upper cervical pain. The incidence of syringomyelia is between 30% and 70%. Surgery is recommended for symptomatic patients. The main purpose of the study is to present the data of children with Chiari type I malformation that were treated surgically in low-volume center and to describe some atypical presentations in children. Materials and methods: At University Medical Centre Maribor, Slovenia, we performed a retrospective study of children with Chiari type I malformation that were treated surgically in the period from 2012 until 2021. The indication for surgery was symptomatic Chiari type I malformation. Suboccipital decompression with laminectomy of at least C1 (in one case also C2) with splitting of dura or duraplasty was performed. In a few cases coagulation of both tonsillar tips was necessary to achieve sufficient decompression and restoration of adequate cerebrospinal fluid (CSF) flow. Results: Ten children (under 18 years of age) underwent surgery for Chiari I malformation. Four patients had atypical presentation. In nine patients there was improvement after surgery. Complication rate was zero with no revision surgery. In one case suboccipital headache persisted. In all cases with preoperative syringomyelia it improved after surgery. Scoliosis improved in two out of three cases. There was no mortality after the procedure. Discussion: When patients with Chiari I malformation become symptomatic, it is recommended to perform surgery as soon as possible. Comparing the techniques; dura-splitting technique has advantages of lesser operation duration, lesser intraoperative bleeding and lower complication rates than duraplasty. Conclusions: The majority of patients with Chiari I malformation improve after surgery. Surgical procedure is safe with very low morbidity and mortality. Surgical technique must be an individualized patient tailored choice