Arrested hydrocephalus and the presyrinx state. Case report.

Hydrocephalus is known to be associated with syringomyelia; however, the association between arrested hydrocephalus and syringomyelia has been reported only once before. This presyrinx state is a recently recognized condition that is known to resolve with proper treatment. This case report highlights a rare association between arrested hydrocephalus and the presyrinx state and outlines the implications for treatment and etiopathogenesis. A 6-year-old girl with arrested hydrocephalus presented with a recent history of difficulty in walking despite no antecedent trauma or infection. An examination revealed macrocrania and features of cervical myelopathy, and magnetic resonance (MR) imaging revealed panventriculomegaly with evidence of the presyrinx state on both T1- and T2-weighted images of the cervical spine. The patient underwent a procedure to insert a ventriculoperitoneal shunt that used a mediumpressure system. After the shunt was inserted, the patient's myelopathic symptoms gradually improved over a period of 6 months. Postoperative MR images obtained 1 year later revealed decompression of the ventricular system and complete resolution of the presyrinx state in the cervical spinal cord. Decompensation in arrested hydrocephalus is a well-known phenomenon. This case illustrates the concept that the presyrinx state may be one of the manifestations of decompensated arrested hydrocephalus. The importance of early recognition of this condition and its implications for the pathogenesis of syringomyelia are discussed.