Venous sinus stenting is a valuable treatment for fulminant idiopathic intracranial hypertension

Abstract

Over the past 10 years, transverse sinus stenting has grown in popularity as a treatment for idiopathic intracranial hypertension. Although promising results have been demonstrated in several reported series, the vast majority of patients in these series have been treated on an elective basis rather than in the setting of fulminant disease with acute visual deterioration. We identified four patients who presented with severe acute vision loss between 2008 and 2012 who were treated with urgent transverse sinus stenting with temporary cerebrospinal fluid (CSF) diversion with lumbar puncture or lumbar drain as a bridge to therapy. All patients presented with headache, and this was stable or had improved at last follow-up. Three patients had improvement in some or all visual parameters following stenting, whereas one patient who presented with severe acute vision loss and optic disc pallor progressed to blindness despite successful stenting. We hypothesize that she presented too late in the course of the disease for improvement to occur. Although the management of fulminant idiopathic intracranial hypertension remains challenging, we believe that transverse sinus stenting, in conjunction with temporary CSF diversion, represents a viable treatment option in the acute and appropriate setting.

Introduction

Pseudotumor cerebri (PTC), known as idiopathic intracranial hypertension (IIH) if no underlying cause is identified, is an uncommon disease characterized by the modified Dandy criteria, which include elevated intracranial pressure (ICP) (>25 cm H₂O on lumbar puncture [LP] in lateral decubitus position in adults) with a normal cerebrospinal fluid (CSF) profile, and typically with papilledema [1]. Although the most common presenting symptom is generalized headache, the symptom with the highest morbidity is vision loss, believed to result from axoplasmic flow stasis with high optic nerve head pressures and eventual optic nerve ischemia, as reviewed in detail recently [2]. Other frequently reported symptoms and signs include pulsatile tinnitus, nausea or vomiting, and double vision, most often from unilateral or bilateral sixth nerve palsies [3].

The most common initial treatment of IIH is medical management with acetazolamide, furosemide, or topiramate; however, many patients either have trouble tolerating the side effects of these medications and their ICP remains poorly controlled despite this treatment. These patients often are treated with optic nerve sheath fenestration (ONSF) or permanent CSF diversion. Although ONSF is effective in many patients, it primarily helps to treat papilledema and often is ineffective in alleviating headaches [3]. Additionally, it is not without complications as up to a 40% complication rate has been reported following this procedure, including the risk of central retinal artery occlusion resulting in permanent, severe visual loss [4]. CSF diversion with lumbar or ventricular shunting is highly effective at treating both headaches and papilledema to prevent vision loss, but requires a more invasive surgical procedure. Also, shunting in PTC rarely requires only a single procedure, as the failure rate of ventriculoperitoneal (VP) shunts has been reported to be as high as 75% within 2 years of surgery, and the failure rate of lumboperitoneal shunts was reported at 86% within 18 months at our institution [5]. Given the problems associated with these procedures, other treatments are clearly needed.

Transverse sinus stenting has grown in popularity as a treatment for PTC since its initial description over 10 years ago [6]. Although a recent systematic review by Lai et al. [7] described similar improvements in visual outcomes across treatment modalities including ONSF, CSF shunting, and transverse sinus stenting, an improvement in headaches was noted following transverse sinus stenting. The incidence of transverse sinus stenosis in PTC has been reported to range between 10–90%, with higher rates found using magnetic resonance venography (MRV), and with a 6.8% incidence in the normal population [8], [9], [10]. Although there is still debate as to whether or not transverse sinus stenosis leads to elevated ICP by causing venous hypertension and decreased CSF absorption or results from elevated ICP causing external compression of the vessel [11], it has been proposed that there may be a cycle where both of these mechanisms play a role [12]. Despite this controversy, the results reported for patients stented for transverse sinus stenosis have been promising [13], [14], [15], [16], [17], [18], [19]. For instance, in the largest reported series by Ahmed et al. [20] all 52 patients treated with stenting had reversal of papilledema and normalized venous pressures, headaches were resolved in 49/52 patients, and 12% of patients required revision of the stent during the mean 2 year follow-up period.

Despite the promising results of the above cited studies, the vast majority of the patients described in them have been treated on an elective basis, and the use of stenting to treat fulminant PTC with acute vision loss has rarely been described. As such, we present our series of four patients who presented with fulminant PTC to demonstrate that transverse sinus stenting, in concert with temporary CSF diversion such as LP or lumbar drain, should be considered as potentially the standard treatment in this clinical scenario.