Longstanding Overt Ventriculomegaly in Adults: Pitfalls in Treatment With Endoscopic Third Ventriculostomy

Conclusions

The study data do not clarify what should be done in the context of seemingly asymptomatic patients with large heads and large ventricles. Neither do they help decide the form that treatment should take, that is, shunting or ETV. Nonetheless, several important conclusions can be derived from this report. In this context, chronic daily headaches are not necessarily caused by increased ICP and may not be ameliorated by intervention. In the absence of overt signs of intracranial hypertension, such as papilledema or increased ICP, headaches may not resolve. Endoscopic third ventriculostomy can be performed with reasonable safety in this patient population and can successfully reestablish normal CSF flow and dynamics. Unless ICP is monitored postoperatively, one cannot assume that it has normalized. If the patient remains symptomatic, further treatment may be needed.

What is the underlying cause of this form of chronic compensated hydrocephalus? Despite the significant degree of ventriculomegaly and large heads, five of the patients in the present study were neurologically normal before their first operation. After the first intervention, all were neurologically normal and independent. The teenager was successful in school, and all five of the adults were in dependent and employed. Terminal CSF absorption problems due to high pressure in the dural venous sinuses can lead to abnormalities in CSF flow and cause aqueductal stenosis that is reversible, as it was in two of the patients in this report. In a select group of these patients, ICP dynamics can be normalized by the use of venous stenting.

Neurosurg Focus. 2007;22(4):E6 © 2007 American Association of Neurological Surgeons