Chiari I malformation: a review of 43 patients.

We have reviewed the presentation, diagnosis, management, and outcome of 43 consecutive patients with the Chiari I malformation who were evaluated over a 12-year period and were managed by a single surgeon. The delay from the time of presentation to that of diagnosis was significantly less in the pediatric group when compared to the adult group. Also, the delay in diagnosis before 1985 was significantly longer than after 1985, the year magnetic resonance imaging became widely available in clinical practice. We were able to show the patients who did not have hydrosyringomyelia were unlikely to develop scoliosis. Surgery resulted in overall improvement in both symptoms and signs, but the improvement in symptoms was more marked than the improvement in signs. There was positive correlation between improvement in hydrosyringomyelia and the improvement in signs and symptoms. Surgery was associated with no significant permanent injury as a result of the procedure in any of the patients. The effect of Chiari surgery on scoliosis was inconclusive.