Treatment of idiopathic intracranial hypertension by endovascular improvement of venous drainage of the brain

Abstract

Idiopathic intracranial hypertension (IIH), also known as pseudotumor cerebri, is a syndrome of elevated intracranial pressure (ICP) in the absence of any known causative factor. Most patients with IIH respond to weight reduction, repeated lumbar punctures and carbonic anhydrase inhibitors, such as acetazolamide and topiramate to reduce cerebrospinal fluid (CSF) production. Despite a number of pathogenetic theories, the cause of IIH remains unknown. With the availability of magnetic resonance (MR) venography and cerebral angiography, venous disease is increasingly being discussed as the etiology of IIH, with a high proportion of patients presenting with nonthrombotic unilateral or bilateral dural venous sinus stenoses. Based on this observation, endovascular stenting of stenotic dural sinuses in patients with IIH has gained popularity. Whether dural venous sinus stenoses are the cause or the consequence of increased ICP is still under debate. In patients with failure of conservative treatment or non-compliance, a more aggressive treatment, such as CSF shunting or surgical optic nerve fenestration, should be performed. For approximately 13 years endovascular stenting of the stenotic sinuses has been used and discussed as an alternative and effective treatment of IIH. Since the first report in 2002, individual cases and case series have been published demonstrating that stents immediately lower the venous pressure gradient, which is associated with clinical improvement. This effect occurs within days or weeks and is permanent in many cases.