Presyrinx in a child with acquired Chiari I malformation.

Spinal cord signal abnormality resulting from alterations in cerebrospinal fluid flow at the craniocervical junction has been termed a presyrinx state. This condition has been described in the adult literature in association with a variety of conditions that cause obstruction to normal cerebrospinal fluid flow. We present a case of presyrinx in a child in the setting of acquired Chiari I malformation caused by lumboperitoneal overshunting. Awareness of the potentially reversible nature of this condition might allow for intervention before irreversible neurological damage has occurred.