Sleep-disordered breathing in Chiari malformation type 1.

Type 1 Chiari malformation is defined as an elongation of the cerebellar tonsils >6 mm below the foramen magnum. Central sleep apnea is a well-recognized sign, and can be an initial presentation, of this malformation. Obstructive sleep apnea is not a widely recognized sign of Chiari type 1 malformation, though there were a few case reports. We present a 13-year-old girl who presented at our respiratory clinic with excessive nighttime snoring. Magnetic resonance imaging revealed a Chiari type 1 malformation requiring decompression. We emphasize the importance of including cervicomedullary junction disorders in the differential diagnosis of apnea, and we review the literature concerning mixed apneas and obstructive sleep apneas in Chiari type 1 malformation.