Article Text
Abstract
Background The effect of dural venous sinus stenting has been investigated for the treatment of idiopathic intracranial hypertension (IIH) but the effect of stenting on the long-term patency of the cortical draining veins, especially the vein of Labbé (VOL), remains unknown.
Methods We reviewed our database of 38 patients with IIH with 41 stented dural venous sinuses between October 2006 and December 2014. Demographic, clinical, and radiological data were reviewed. Follow-up catheter angiographic data were included when available.
Results Stent placement spanned the ostium of the VOL in 35 patients (92.1%), with no immediate effect on the drainage of the VOL. Follow-up angiography (mean 35.1 months, range 1.7–80.7 months) was available in 24 patients, 21 of whom had stents spanning the VOL ostium. The VOL remained patent without occlusion or drainage alteration in all 21 patients. There were no immediate or long-term intracranial complications.
Conclusions Dural venous sinus stenting for patients with IIH does not affect the immediate or long-term patency of the VOL and is not associated with intracranial complications.
- Blood Flow
- Hydrocephalus
- Intracranial Pressure
- Stenosis
- Stent
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Introduction
Although the etiology of idiopathic intracranial hypertension (IIH), also known as pseudotumor cerebri, is not completely understood, recent evidence suggests a potential treatment for dural venous sinus stenosis in patients with IIH.1 ,2 Stenting of dural venous sinus stenosis has shown promise as an effective treatment in these patients with IIH.3–5 We recently reported our excellent long-term stent patency results,6 which are similar to other reports.4
Patients with IIH most commonly develop stenosis in the transverse sinus or at the transverse–sigmoid junction.3 Because the inferior anastomotic vein of Labbé (VOL) usually drains into the transverse sinus or the transverse–sigmoid junction,7 stenting of these sinuses for IIH often spans the ostium of the VOL. Serious complications, such as malignant cerebral edema, cerebral venous infarction, and intraparenchymal hemorrhage, have been reported after occlusion or thrombosis of the VOL.8–10 However, there are no reports on the immediate and long-term patency of the VOL or associated cortical complications in patients undergoing dural venous sinus stenting across the VOL ostium. Here we report on a large cohort of patients who underwent dural venous sinus stenting for IIH, with a focus on angiographic outcome of VOL patency.
Methods
We performed a retrospective review of our prospectively maintained registry of patients with IIH undergoing dural venous sinus stenting between October 2006 and December 2014. Relevant demographic and radiological data were extracted and reviewed. Patients with at least one follow-up angiogram were included in the analysis. The incidence of stenting across the ostium of the VOL, long-term VOL patency, and neurological complications were recorded.
Patient selection, technique, and antithrombotic medication
A previous report has described the indications and the technique for venous sinus stenting for IIH.5 In brief, patients were diagnosed with IIH based on clinical presentation (headache, papilledema) and objective physiological data (elevated intracranial pressure). Patients underwent cerebral venography with venous pressure measurements. Venographic stenosis >50% and a venous pressure gradient >10 mm Hg were required before venous stenting was considered. Stenting was performed via a transfemoral approach using the Zilver biliary self-expanding bare metal stent (Cook Medical, Winston-Salem, North Carolina, USA). All patients were placed on dual antiplatelet medication (aspirin 325 mg daily and clopidogrel 75 mg daily) at least 3 days before the stent procedure. These medications were maintained for 3 months after stent placement, at which time clopidogrel was discontinued. Follow-up angiography was performed at multiple time points via the carotid artery ipsilateral to the stent placement in all patients.
Results
We placed stents in 41 sinuses in 38 patients with IIH during the study period. The average number of stents placed per patient was 1.25, and stent placement spanned the ostium of the VOL in 35 patients (92.1%). No immediate occlusions of the VOL were observed, nor were any immediate intracranial complications encountered.
Twenty-four patients (63%) underwent at least one follow-up angiography study with visualization of cortical venous drainage. The average length of angiographic follow-up was 35.1 months (range 1.7–80.7 months). There were no cases of VOL thrombosis, occlusion, or altered drainage pattern in the 21 patients in whom stenting spanned the VOL ostium (representative case shown in figure 1). Four cases of mild in-stent stenosis were observed but did not require treatment. No patients had neurological complications at follow-up.
Discussion
These results demonstrate that, despite the stent spanning the ostium of the VOL in the majority of patients during venous sinus stenting for the treatment of IIH, the VOL remained patent in all instances. Long-term follow-up data showed that the long-term patency of the VOL is not affected by transverse sinus stenting, despite discontinuing clopidogrel and maintaining only aspirin monotherapy 3 months after the procedure.
Typical treatments of IIH are cerebrospinal fluid diversion to reduce intracranial pressure or optic nerve sheath fenestration (ONSF) to reduce intraocular pressure. Shunting procedures are associated with shunt infection and failure, requiring operative revision in up to 75% of ventriculoperitoneal (VPS) and 86% of lumboperitoneal shunts (LPS) in IIH patients.11 However, these procedures are associated with only moderate symptomatic relief. A recent analysis comparing ONSF, VPS, LPS, and venous sinus stenting for IIH demonstrated a significant advantage of stenting over other modalities in improving visual acuity, papilledema, and headache.12
Despite this report of excellent outcomes in a clinical series of carefully selected patients, it is important to evaluate critically the safety and long-term efficacy of venous sinus stenting in the treatment of IIH. Thrombosis or occlusion of the VOL can lead to significant and even life-threatening neurological complications.9 ,10 ,13–16 The importance of preserving this vein during temporal lobe and skull base surgery has been well described.15–17 Although specific data on venous occlusion after dural venous stenting are unknown, reports of stenting across major cerebral arterial branches using similarly high-porosity stents have shown no branch vessel occlusion.18 The pathobiology of in-stent stenosis and vessel occlusion undoubtedly differs in the dural venous sinuses compared with cerebral arteries, although histological studies have not yet been performed to confirm this.
There are several limitations to this study. Although data were collected prospectively, this is a retrospective review of angiographic outcomes and it is therefore subject to the standard limitations of any retrospective study. Additionally, not all patients from the entire cohort underwent angiographic follow-up, so these patients could potentially harbor an occluded VOL. However, the lack of incidence of VOL occlusion in the patients who did undergo substantial long-term angiographic follow-up, along with the lack of neurological complications in any patient (including those with clinical but not angiographic follow-up), lend confidence to our hypothesis that VOL occlusion after dural sinus stenting for IIH is exceedingly rare.
Conclusions
Dural venous sinus stenting across the ostium of the VOL does not lead to venous occlusion or intracranial complications.
References
Footnotes
Contributors MRL collected and analyzed the data and drafted the manuscript. FCA conceived the work, acquired and analyzed the data and critically revised the manuscript; he is the guarantor. AFD, MYSK and CBM collected and analyzed the data. CGM acquired the data. All authors critically revised the manuscript prior to submission.
Competing interests None declared.
Ethics approval This study was approved by the Institutional Review Board at St Joseph's Hospital and Medical Center.
Provenance and peer review Not commissioned; externally peer reviewed.