Idiopathic intracranial hypertension

The cause of idiopathic intracranial hypertension (IIH) has long been a mystery and continues to be. There are three major theories of the cause of IIH1: 1) increased resistance to CSF absorption; 2) increased CSF production; and 3) within the past few years, increased venous sinus pressure. In fact, increased venous sinus pressure is now hypothesized to be the cause of IIH. Venous sinus occlusion and elevated venous sinus pressure are a proven cause of elevated intracranial pressure. MRI and MR venography now make it easier to identify venous sinus occlusion. Biousse et al.6 have shown that 54 of 160 patients with venous sinus occlusion had only symptoms of headache and papilledema that could have been construed as IIH. Many had normal CSF constituents and elevated CSF pressure. In Melbourne, King et al.2 have measured intracranial venous sinus pressures with transducers in …