Chiari type I malformation, glossopharyngeal neuralgia and central sleep apnoea in a child.

We describe the case of an 8-year-old child who presented with sleep breathing disorders associated with glossopharyngeal neuralgia. Polysomnographic studies showed central sleep apnoea lasting 10 to 18 seconds in an average frequency of 63 times for every hour of sleep. Magnetic resonance imaging (MRI) studies showed a caudal displacement of the cerebellar tonsils down to C3 level, associated with a syringomyelic cavity in the upper cervical cord and an extramedullary cystic collection at C2. Surgical decompression of the cranio-cervical junction completely relieved the apnoea and the glossopharyngeal neuralgia immediately following the procedure. MRI study performed one month later showed the complete disappearance of the syringomyelic cavity. Two years later this child remains asymptomatic. In childhood the association of Chiari type I malformation with sleep apnoea and glossopharyngeal neuralgia has not been previously reported. The successful outcome after surgery suggests a compressive mechanism on the brainstem and on the IX cranial nerve to explain these two clinical features in our patient.