Isolated central sleep apnea in type I Chiari malformation: improvement after surgery.

Sleep apnea is a rare but well-known clinical feature of disorders of the craniocervical junction. It may be obstructive or central in nature, and rarely presents without other neurological symptoms. We report the cases of two children, presenting with isolated central sleep apnea leading to a diagnosis of type I Chiari malformation. Surgical treatment resulted in a dramatic improvement in respiratory parameters during sleep, both clinically and on polysomnography. We discuss this uncommon presentation of type I Chiari malformation and suggest that it be considered in the differential diagnosis of central sleep apnea in children, as posterior fossa decompression may lead to significant clinical improvement.