Introduction: Adults with spina bifida and associated hydrocephalus are exposed to multiple risk factors for the development of chronic headache. The management of these patients can be complex and misdiagnosis can precipitate unnecessary shunt revision. This study aims to evaluate the usefulness of intracranial pressure (ICP) monitoring as a diagnostic tool in these cases and to look at the causes of chronic headaches and treatment outcomes for this patient population.
Methods: All patients over the age of 18 years with a diagnosis of spina bifida and shunted hydrocephalus who had undergone inpatient or outpatient neurosurgical review within the last 10 years were identified in our hospital database. Case notes were then retrospectively reviewed to identify all patients who had undergone either inpatient or outpatient evaluation of chronic headaches (defined as a headache of at least one month's duration) occurring in the absence of any other symptoms or signs suggestive of raised intracranial pressure (ICP). The incidence, causes, management and outcome of chronic headache in these patients was determined.
Results: 42 patients were identified, mean age 30 years (range 18 - 59). All had undergone lifelong follow-up. All had previously undergone shunt insertion for hydrocephalus. 16 had undergone endoscopic third ventriculostomy (ETV). 11 had undergone choroid plexus coagulation. 55 % (23/42) of patients underwent investigation for 1 or more episodes of chronic headache. Recurrent hydrocephalus due to shunt malfunction or ETV failure was excluded by ICP monitoring using either an intraparenchymal transducer or monitoring via a ventricular access device. All patients underwent repeat imaging, using CT and/or MR imaging. Identified causes of headache included: shunt blockage; shunt overdrainage; ETV failure and symptomatic Arnold-Chiari malformation. A history of choroid plexus coagulation (CPC) as an infant was associated with a decreased risk of chronic headache in later life (p = 0.02). In 8 patients no definite cause for headaches was identified, in 4 of these patients symptoms resolved spontaneously, the remainder required specialist pain management.
Conclusions: The aetiology of chronic headaches in this patient group is multifactorial. In the absence of other clinical symptoms or signs of raised ICP, ICP monitoring is an invaluable adjunct to management. 10 % of hydrocephalic adult spina bifida patients required specialist pain management for control of chronic idiopathic headache.