Chiari malformation type I with an associated syrinx presenting as acute central cord syndrome in a child: illustrative case.

backgroundChiari malformation type I (CM-I) usually manifests with chronic symptoms. The most common symptoms observed in the pediatric population include headache, neck pain, vertigo, and ataxia. Some unusual presentations have been reported in children, including a diversity of acute neurological deficits in previously asymptomatic patients. OBSERVATIONS: The authors report the case of a 4-year-old previously healthy boy who presented to the emergency department with clinical findings of incomplete cervical spinal cord injury and respiratory function decline after a minor fall. The cervical spine CT scan did not show evidence of fracture. MRI revealed findings of CM-I, a complex cervicothoracic cyst syrinx, and spinal cord signal hyperintensity. The patient required urgent intubation and mechanical ventilation for airway protection and was thought to have an ascending cervical cord injury. He underwent suboccipital craniectomy, C1 and C2 partial laminectomies, and patch duraplasty. After surgery, he showed progressive improvement and was discharged to acute inpatient rehabilitation. Postoperative MRI showed near-complete resolution of the cord edema and the syrinx. LESSONS: The authors describe the case of a previously healthy child presenting with acute central cord syndrome and a decline in respiratory effort as the initial presentation of CM-I with a syrinx. Although rare, clinicians should consider CM-I in the differential diagnosis of pediatric patients presenting with acute cervical spinal cord injury, especially if imaging does not show spinal fractures. https://thejns.org/doi/10.3171/CASE24829.