Shunt-related headaches: the slit ventricle syndromes

Purpose The purpose of this work is to review the pathophysiology and treatment of severe headache disorders in patients having a shunt for hydrocephalus. Materials and methods The literature on the management of the slit ventricle syndrome is reviewed as well as an assessment of personal experiences over a 30-year period in the management of severe headache disorders in shunted patients. Results If the slit ventricle syndrome is defined as severe, life-modifying headaches in patients with shunts and normal or smaller than normal ventricles with ventricular shunts for the treatment of hydrocephalus, there are five different pathophysiologies that are involved in the process. These pathologies are defined by intracranial pressure measurement as severe intracranial hypotension analogous to spinal headaches, intermittent obstruction of the ventricular catheter, intracranial hypertension with small ventricles and a failed shunt (normal volume hydrocephalus), intracranial hypertension with a working shunt (cephalocranial hypertension), and shunt-related migraine. The treatment of these conditions and identifying patients with each condition are facilitated by attempting to remove the shunt. Conclusions Following the analysis of attempts to remove shunts, there are three possible outcomes. In about a quarter of patients, the shunt can be removed without having to be replaced. This is most common in patients treated in infancy for post-hemorrhagic hydrocephalus or patients shunted early after or before brain tumor surgery. Another half of patients have increased intracranial pressure and enlarged ventricles. In these patients, there is an 80% success rate for endoscopic third ventriculostomy. Finally, the most severe form of the slit ventricle syndrome involves intracranial hypertension without ventriculomegaly, which is managed optimally by shunt strategies that emphasize drainage of the cortical subarachnoid space such as lumbo-peritoneal shunts or shunts that include cisterna magna catheters.