Comprehensive approach to Chiari malformation in pediatric patients.

Chiari malformation is a developmental disorder that is often associated with other abnormalities of the cerebrospinal axis. Despite widespread recognition of this association, there is relatively little information on the treatment of these coexisting disorders in the setting of cerebellar tonsillar ectopia. In an effort to improve the care provided to pediatric patients with Chiari malformations the authors reviewed their management practices over the last 20 years. Specifically, they recorded presenting symptoms, radiological studies, comorbidities, and management (surgical and nonsurgical) of 112 patients (all < 20 years of age) with Chiari malformation without myelodysplasia. They found an associated syrinx in 29% of patients, basilar invagination in 17%, and scoliosis in 14%. The basal angle varied from 120 to 190 degrees and Boogard's angle varied from 120 to 220 degrees ; both angles were larger than those measured in normal controls. The vertical height of the posterior fossa was shortened and the volume decreased as compared with normal controls. The surgical management of this group of patients included posterior decompressive (44%), combined transoral and posterior decompressive (31%), combined posterior decompressive and posterior fusion (8%), and multiple posterior decompressive procedures in the same patient (5%). The authors conclude that pediatric patients with a Chiari malformation should be specifically examined for evidence of additional craniovertebral malformations so that procedures are directed at correcting both the comorbidities and the herniation of the cerebellar tonsils through the foramen.