Clinical outcomes in patients with Chiari I malformation: a review of 27 cases.

BACKGROUND: Chiari I malformation is a congenital maldevelopment defined as downward herniation of the cerebellar tonsils through the foramen magnum. It has been treated using a variety of surgical procedures. Surgical outcomes have been reported with varying results throughout the literature.
METHODS: We retrospectively reviewed 27 patients with Chiari I malformation operated at the University Hospital during a 9-year period from 1988 to 1997. We assessed preoperative and postoperative signs and symptoms in all the patients including headache, neck pain, nystagmus, vertigo, weakness, spasticity, atrophy, numbness, pain and temperature dissociation, diplopia, dysphagia, and sphincter dysfunction. Each patient was analyzed to determine if there was an arrest in the progression of the disease after surgical intervention.
RESULTS: Syringomyelia was present in 59% of the patients. Only 1 patient who presented with neck pain improved. One patient reported new onset headache, and one patient described his headache resolved. Vertigo resolved in three patients; two patients stated mild improvement, and one patient reported worsening. Nystagmus improved or resolved in six patients. Weakness improved in only two patients who did not have syringomyelia. Dysphagia improved in two patients, and in the others it remained unchanged. Diplopia, spasticity, atrophy, and numbness remained unchanged.
CONCLUSIONS: Our study provides evidence that the main benefit of the surgical management in patients with Chiari I malformation with or without syringomyelia is to arrest the progression of the disease.