Effect of venous stenting on intracranial pressure in idiopathic intracranial hypertension

Novel Approaches to the Treatment of Idiopathic Intracranial Hypertension

PURPOSE OF REVIEW

Idiopathic intracranial hypertension (IIH) typically affects women of childbearing age, is associated with recent weight gain, and can result in debilitating headache as well as papilledema that can cause vision loss. There have been advances in the medical and surgical treatment of affected patients with IIH that can improve outcomes and tolerability of therapy.

RECENT FINDINGS

Medical treatment with agents that lower intracranial pressure through pathways other than carbonic anhydrase inhibition are being developed, and medically-directed weight loss as well as bariatric surgery now may be considered as primary therapy. New surgical options including venous sinus stenting have shown efficacy even with cases of severe vision loss. Our treatment options for IIH patients are becoming more diverse, and individualized treatment decisions are now possible to address specific components of the patient's disease manifestations and to lead to IIH remission.

Interrelation Between Cerebrospinal Fluid Pressure, Intracranial Morphology and Venous Hemodynamics Studied by 4D Flow MRI

PURPOSE

To quantify the effects of CSF pressure alterations on intracranial venous morphology and hemodynamics in idiopathic intracranial hypertension (IIH) and spontaneous intracranial hypotension (SIH) and assess reversibility when the underlying cause is resolved.

METHODS

We prospectively examined venous volume, intracranial venous blood flow and velocity, including optic nerve sheath diameter (ONSD) as a noninvasive surrogate of CSF pressure changes in 11 patients with IIH, 11 age-matched and sex-matched healthy controls and 9 SIH patients, before and after neurosurgical closure of spinal dural leaks. We applied multiparametric MRI including 4D flow MRI, time-of-flight (TOF) and T2-weighted half-Fourier acquisition single-shot turbo-spin echo (HASTE).

RESULTS

Sinus volume overlapped between groups at baseline but decreased after treatment of intracranial hypotension (p = 0.067) along with a significant increase of ONSD (p = 0.003). Blood flow in the middle and dorsal superior sagittal sinus was remarkably lower in patients with higher CSF pressure (i.e., IIH versus controls and SIH after CSF leak closure) but blood flow velocity was comparable cross-sectionally between groups and longitudinally in SIH.

CONCLUSION

We were able to demonstrate the interaction of CSF pressure, venous volumetry, venous hemodynamics and ONSD using multiparametric brain MRI. Closure of CSF leaks in SIH patients resulted in symptoms suggestive of increased intracranial pressure and caused a subsequent decrease of intracranial venous volume and of blood flow within the superior sagittal sinus while ONSD increased. In contrast, blood flow parameters from 4D flow MRI did not discriminate IIH, SIH and controls as hemodynamics at baseline overlapped at most vessel cross-sections.

Venous sinus stenting for idiopathic intracranial hypertension: An updated Meta-analysis

BACKGROUND

Idiopathic intracranial hypertension (IIH) is characterized by elevated intracranial pressure and primarily affects obese women of reproductive age. Venous sinus stenting (VSS) is a surgical procedure used to treat IIH, but its safety and efficacy are still controversial.

METHODS

A systematic review and meta-analysis were conducted following PRISMA guidelines. Multiple databases were searched for studies evaluating the safety and efficacy of VSS in IIH patients and meta-analysis was performed to pool the data.

RESULTS

A total of 36 studies involving 1066 patients who underwent VSS were included. After VSS, a significant reduction in trans-stenotic gradient pressure was observed. Patients also showed significantly lower cerebrospinal fluid (CSF) opening pressure. Clinical outcomes demonstrated improvement in tinnitus (95%), papilledema (89%), visual disturbances (88%), and headache (79%). However, 13.7% of patients experienced treatment failure or complications. The treatment failure rate was 8.35%, characterized by worsening symptoms and recurrence of IIH. The complications rate was 5.35%, including subdural hemorrhage, urinary tract infection, stent thrombus formation, and others.

CONCLUSION

VSS appears to be a safe and effective treatment option for IIH patients who are unresponsive to medical therapy or have significant visual symptoms. However, long-term outcomes and safety of the procedure require further investigation.

Future Directions and Innovations in Venous Sinus Stenting

This review explores the future role of venous sinus stenting (VSS) in the management of idiopathic intracranial hypertension and pulsatile tinnitus. Despite its favorable safety profile and clinical outcomes compared with traditional treatments, VSS is not yet the standard of care for these conditions, lacking high-level evidence data and guidelines for patient selection and indications. Current and recently completed clinical trials are expected to provide data to support the adoption of VSS as a primary treatment option. Additionally, VSS shows potential in treating other conditions, such as dural arteriovenous fistula and cerebral venous sinus thrombosis, and it is likely that the procedure will continue to see an expansion of its approved indications. The current lack of dedicated venous stenting technology is being addressed with promising advancements, which may improve procedural ease and patient outcomes. VSS also offers potential for expansion into modulation of brain electrophysiology via endovascular routes, offering exciting possibilities for neurodiagnostics and treatment of neurodegenerative disorders.

Challenges in the use of Venous Sinus Stenting in the Treatment of Idiopathic Intracranial Hypertension and Pulsatile Tinnitus

Although numerous case series and meta-analyses have shown the efficacy of venous sinus stenting (VSS) in the treatment of idiopathic intracranial hypertension and idiopathic intracranial hypertension-associated pulsatile tinnitus, there remain numerous challenges to be resolved. There is no widespread agreement on candidacy; pressure gradient and failed medical treatment are common indications, but not all clinicians require medical refractoriness as a criterion. Venous manometry, venography, and cerebral angiography are essential tools for patient assessment, but again disagreements exist regarding the best, or most appropriate, diagnostic imaging choice. Challenges with the VSS technique also exist, such as stent choice and deployment. There are considerations regarding postprocedural balloon angioplasty and pharmacologic treatment, but there is insufficient evidence to formalize postoperative decision making. Although complications of VSS are relatively rare, they include in-stent stenosis, hemorrhage, and subdural hematoma, and the learning curve for VSS presents specific challenges in navigating venous anatomy, emphasizing the need for wider availability of high-quality training. Recurrence of symptoms, particularly stent-adjacent stenosis, poses challenges, and although restenting and cerebrospinal fluid-diverting procedures are options, there is a need for clearer criteria for retreatment strategies. Despite these challenges, when comparing VSS with traditional cerebrospinal fluid-diverting procedures, VSS emerges as a favorable option, with strong clinical outcomes, lower complication rates, and cost-effectiveness. Further research is necessary to refine techniques and indications and address specific aspects of VSS to overcome these challenges.

Idiopathic Intracranial Venous Hypertension: Toward a Better Understanding of Venous Stenosis and the Role of Stenting in Idiopathic Intracranial Hypertension

BACKGROUND

Venous sinus stenosis, typically at the junction of the transverse and sigmoid sinus, is increasingly recognized as a contributor to the pathophysiology of idiopathic intracranial hypertension (IIH), whether it be the intrinsic type that does not reverse with normalization of intracranial pressure or the extrinsic type, which does. Efforts to treat the stenosis and reduce the associated transstenotic gradient through placement of a stent at the site of stenosis have been studied over the past 2 decades, primarily through retrospective studies, with variable emphasis on formal visual testing and direct assessment of poststent opening pressure. Most studies have presented evidence for utilization of stenting as an alternative to cerebrospinal fluid shunting or optic nerve sheath fenestration in patients with IIH who harbor the stenosis and are refractory to or intolerant of intracranial pressure-lowering medications, but an assessment of the current data is needed to better understand the role of stenting for this patient population.

EVIDENCE ACQUISITION

A search in PubMed was made for "IIH," "papilledema," and "venous stenting." Data pre and post stenting, including symptoms attributable to IIH, intracranial pressure, papilledema, retinal nerve fiber layer thickening on optical coherence tomography, and visual field assessment (mean deviation), were collected. Need for retreatment and complications were assessed among all studies. Studies using stenting for special circumstances, such as cerebrospinal leaks or for stenosis along anomalous vessels, were reviewed.

RESULTS

In total, 49 studies (45 retrospective and 4 prospective) and 18 case reports (with 3 or less patients) were found and included in the analysis, for a total of 1,626 patients. In 250 patients in whom poststent intracranial pressure was measured, the mean value was 19.7 cm H 2 O, reduced from a mean of 33 cm H 2 O. Transient visual obscurations resolved in 79.6% of 201 patients who complained of it, pulsatile tinnitus resolved in 84.7% of 515, diplopia resolved in 93% of 86 patients, and nonspecific visual symptoms such as "blurry vision" improved in 76.2% of 537 patients. Headaches resolved in 36% and improved in a further 40.7% of 1,105 patients in whom they were documented before stenting. Of 1,116 with papilledema, 40.8% demonstrated resolution and 38.2% improvement. The mean retinal nerve fiber layer thickness improved from 170.2 µm to 89.2 µm among 402 eyes in which optical coherence tomography was used to measure it. Among 135 eyes in which formal visual fields were performed pre and post stenting, the prestent average mean deviation of -7.35 dB improved to -4.72 dB after stenting. Complications associated with stenting included in-stent stenosis or thrombosis, subdural hematoma, intracerebral hematoma, cerebral edema, stent migration, and death. A recurrence of symptoms requiring a follow-up surgical intervention occurred in 9%.

CONCLUSIONS

A growing body of evidence supports the use of venous sinus stenting as a viable option for medically refractory IIH, especially when papilledema threatens visual function. Complication and failure rates seem to be similar to alternative surgical approaches, although serious neurological sequalae can rarely occur. Emerging studies evaluating stent type, including novel stents designed for use in the venous system, may help improve ease of the procedure and long-term success rates. Prospective head-to-head studies are needed to better understand the performance of stenting compared with other interventions.

Stenting versus medical treatment for idiopathic intracranial hypertension: a matched-control study

BACKGROUND

This prospective cohort study compared the outcomes of stenting and medical treatment for patients with idiopathic intracranial hypertension (IIH) and venous sinus stenosis (VSS).

METHODS

In this single-center cohort study, patients with IIH and VSS were evaluated between January 2014 and December 2019 with follow-up periods of 1, 3, and 6 months. The patients received either stenting or medical treatment. The two groups underwent 1:1 matching using propensity score analysis, and the clinical outcomes were compared.

RESULTS

Following 1:1 matching, 36 patients who underwent stenting and 36 who underwent medical treatment were matched. The median improvements in the papilledema Frisén grade were greater in the stenting group at 1 month (-2 vs 0), 3 months (-3 vs -1), and 6 months (-3 vs -1) than in the medical treatment group. Patients who received stenting treatment had a significantly higher prevalence of complete resolution of their respective symptoms (headache, tinnitus, or visual disturbances) at 3 months (58.3% vs 13.9%, OR 8.68, 95% CI 2.74 to 27.52) and 6 months (80.6% vs 22.2%, OR 14.50, 95% CI 4.64 to 45.32) than those receiving medical treatment.

CONCLUSIONS

This matched-control study shows that stenting has a greater efficacy rate and rapid resolution of papilledema and its respective symptoms compared with medical treatment.

Idiopathic intracranial hypertension imaging approaches and the implications in patient management

Idiopathic intracranial hypertension (IIH) represents a clinical disease entity without a clear etiology, that if left untreated, can result in severe outcomes, including permanent vision loss. For this reason, early diagnosis and treatment is necessary. Historically, the role of cross-sectional imaging has been to rule out secondary or emergent causes of increased intracranial pressure, including tumor, infection, hydrocephalus, or venous thrombosis. MRI and MRV, however, can serve as valuable imaging tools to not only rule out causes for secondary intracranial hypertension but can also detect indirect signs of IIH resultant from increased intracranial pressure, and demonstrate potentially treatable sinus venous stenosis. Digital subtraction venographic imaging also plays a central role in both diagnosis and treatment, providing enhanced anatomic delineation and temporal flow evaluation, quantitative assessment of the pressure gradient across a venous stenosis, treatment guidance, and immediate opportunity for endovascular therapy. In this review, we discuss the multiple modalities for imaging IIH, their limitations, and their contributions to the management of IIH.

The Case of a Patient with Idiopathic Intracranial Hypertension Who Required Additional Stenting for Stent-Adjacent Stenosis

Objective

We report the case of a patient with recurred idiopathic intracranial hypertension (IIH) with transverse sinus (TS) stenosis after initial stenting, which was treated with additional stent placed in tandem to the secondarily occurred stent-adjacent stenosis (SAS).

Case Presentation

A 41-year-old woman complained of reduced visual acuity and blurred vision, and presented with papilledema. Lumbar puncture revealed an opening pressure of 36 cmH₂O. MRI revealed no space-occupying lesions, and the patient was diagnosed with IIH based on the modified Dandy criteria. MR venography revealed stenosis in the right and hypoplastic left TS. The patient complained of headache and neck pain after each lumbar puncture for examination. Venous sinus stenting (VSS) was performed in the right TS. One month after stenting, follow-up angiography revealed stenosis in the remaining parts of TS. Five months after stenting, IIH recurred, and SAS was detected on angiography. An additional stenting procedure was performed. Three months after the second treatment, her symptoms disappeared and cerebrospinal fluid pressure was normalized.

Conclusion

Patients with post-VSS recurrent IIH may develop restenosis in the remaining parts of TS at variable progression speeds. In this case, angiography revealed gradually advancing stenosis that seemed to form SAS at the time of recurrence. If the initial VSS is effective for IIH, SAS can also be treated effectively and less invasively with a second stent placement covering the entire TS length.

Intracranial Venous Hypertension and Venous Sinus Stenting in the Modern Management of Idiopathic Intracranial Hypertension

Idiopathic intracranial hypertension (IIH) is a debilitating condition that has traditionally been difficult to treat. In recent years, there has been increasing focus on the role of intracranial venous hypertension in the pathophysiology of IIH. Based on increased understanding of this pathophysiology, venous sinus stenting (VSS) has emerged as a safe and reliable treatment for a certain population of patients with IIH. Stratifying patients with IIH based on the status of their venous outflow can provide insight into which patients may enjoy reduction in their symptoms after VSS and provides information regarding why some patients may have symptom recurrence. The traditional view of IIH as a disease due to obesity in young women has been cast into doubt as the understanding of the role of intracranial venous hypertension has improved.

Dural venous sinus stenting in the treatment of idiopathic intracranial hypertension: A systematic review and critique of literature

Idiopathic intracranial hypertension (IIH) is increased intracranial pressure without a known cause. Dural venous sinus stenting (DVSS) is a relatively new intervention for treatment of IIH refractory to medical therapy and lifestyle modifications. In this review, we outline various hypotheses of IIH pathogenesis and describe the role of venous sinus stenosis and the technical details of DVSS. We also present a summary and critique of the available evidence describing the outcomes of DVSS in IIH and review the evidence-based guidelines for this procedure. We conclude that, although many studies have shown generally favorable outcomes of DVSS in patients with IIH, most have serious limitations, the most common one being paucity of pre- and postprocedure ophthalmological data. Thus, there is not enough available evidence to conclude whether DVSS is an effective procedure for treatment of IIH. We also present the most commonly used indications for DVSS as described in the literature and stress the importance of neuro-ophthalmological assessment before and after the procedure to monitor response and potential complications.

Reviewing the Recent Developments in Idiopathic Intracranial Hypertension

There is increasing evidence and appreciation of idiopathic intracranial hypertension (IIH) in medicine. The pathological processes underlying raised intracranial pressure are being studied, with new insights found in both hormonal dysregulation and the metabolic neuroendocrine axis. These will potentially lead to novel therapeutic targets for IIH. The first consensus guidelines have been published on the investigation and management of adult IIH, and the International Headache Society criteria for headache attributable to IIH have been modified to reflect our evolving understanding of IIH. Randomized clinical trials have been published, and a number of studies in this disease area are ongoing.

Idiopathic intracranial hypertension with stenosis of a solitary occipital venous sinus treated with stenting

A 47-year-old live kidney-donor woman presented with headaches and blurred vision. Neuro-ophthalmological examination demonstrated papilledema and right eye inferior nasal defect. Brain MRV showed no sinus thrombosis but solitary right venous sinus draining the torcular Herophili to right jugular bulb. Lumbar puncture revealed elevated CSF opening pressure of 40 cm H₂O with normal composition. She was diagnosed with idiopathic intracranial hypertension (IIH). She did not tolerate medical management and declined CSF diversion surgery. Cerebral angiography and venography showed venous outflow drainage from torcular Herophili through a solitary occipital sinus which has distal severe stenosis and pressure gradient of 10 mmHg. Balloon angioplasty and stenting of the occipital sinus were performed. Post-stenting, the stenosis and pressure gradient resolved. At 3-months follow-up, her symptoms and papilledema had resolved and CSF opening pressure was normal at 15 cm H2O. Aberrant cerebral venous anatomy may cause IIH and can be treatable with neuroendovascular techniques.

A systematic review of surgical treatments of idiopathic intracranial hypertension (IIH)

Idiopathic intracranial hypertension denotes raised intracranial pressure in the absence of an identifiable cause and presents with symptoms relating to elevated ICP, namely headaches and visual deterioration. Treatment of IIH aims at reducing intracranial pressure, relieving headache and salvaging patients' vision. Surgical interventions are recommended for medically refractory IIH and include CSF diversion techniques, optic nerve sheath fenestration, bariatric surgery and venous sinus stenting. Prospective studies on the surgical options for IIH are scant and no evidence-based guidelines for the surgical management of medically refractory IIH have been established. A search in Cochrane Library, MEDLINE and EMBASE from 1 January 1985 to 19 April 2019 for controlled or observational studies on the surgical treatment of IIH (defined in accordance with the modified Dandy or the modified Friedman criteria) in adults yielded 109 admissible studies. VSS improved papilledema, visual fields and headaches in 87.1%, 72.7% and 72.1% of the patients respectively, with a 2.3% severe complication rate and 11.3% failure rate. CSF diversion techniques diminished papilledema, visual field deterioration and headaches in 78.9%, 66.8% and 69.8% of the cases and are associated with a 9.4 severe complication rate and a 43.4% failure rate. ONSF ameliorated papilledema, visual field defects and headaches in 90.5, 65.2% and 49.3% of patients. Severe complication rate was 2.2% and failure rate was 9.4%. This is currently the largest systematic review for the available operative modalities for IIH. VSS provided the best results in headache resolution and visual outcomes, with low failure rates and a very favourable complication profile. In light of this, VSS ought to be regarded as the first-line surgical modality for the treatment of medically refractory IIH.

Understanding the complex pathophysiology of idiopathic intracranial hypertension and the evolving role of venous sinus stenting: a comprehensive review of the literature

Idiopathic intracranial hypertension (IIH) is a disease defined by elevated intracranial pressure without established etiology. Although there is now consensus on the definition of the disorder, its complex pathophysiology remains elusive. The most common clinical symptoms of IIH include headache and visual complaints. Many current theories regarding the etiology of IIH focus on increased secretion or decreased absorption of cerebrospinal fluid (CSF) and on cerebral venous outflow obstruction due to venous sinus stenosis. In addition, it has been postulated that obesity plays a role, given its prevalence in this population of patients. Several treatments, including optic nerve sheath fenestration, CSF diversion with ventriculoperitoneal or lumboperitoneal shunts, and more recently venous sinus stenting, have been described for medically refractory IIH. Despite the availability of these treatments, no guidelines or standard management algorithms exist for the treatment of this disorder. In this paper, the authors provide a review of the literature on IIH, its clinical presentation, pathophysiology, and evidence supporting treatment strategies, with a specific focus on the role of venous sinus stenting.

Dural sinus collapsibility, idiopathic intracranial hypertension, and the pathogenesis of chronic migraine

Available evidences suggest that a number of known assumption on idiopathic intracranial hypertension (IIH) with or without papilledema might be discussed. These include (1) the primary pathogenetic role of an excessive dural sinus collapsibility in IIH, allowing a new relatively stable intracranial fluids pressure balance at higher values; (2) the non-mandatory role of papilledema for a definite diagnosis; (3) the possibly much higher prevalence of IIH without papilledema than currently considered; (4) the crucial role of the cerebral compliance exhaustion that precede the raise in intracranial pressure and that may already be pathologic in cases showing a moderately elevated opening pressure; (5) the role as "intracranial pressure sensor" played by the trigeminovascular innervation of dural sinuses and cortical bridge veins, which could represent a major source of CGRP and may explain the high comorbidity and the emerging causative link between IIHWOP and chronic migraine (CM). Accordingly, the control of intracranial pressure is to be considered a promising new therapeutic target in CM.

Headache attributed to cranial venous sinus stenting: A case series and literature review

Background

The diagnostic criteria for headache attributable to cranial venous sinus stenting were first formalized in the recently published third edition of the International Classification of Headache Disorders (ICHD-3). However, the diagnostic criteria for headache caused by cranial venous sinus stenting are based on very few data and the condition is poorly characterized.

Objectives

To validate the diagnostic criteria for cranial venous sinus stenting headache by retrospectively studying the characteristics of headache in patients with isolated pulsatile tinnitus who underwent curative cranial venous sinus stenting and who had not previously complained of headache.

Patients and methods

We retrospectively studied clinical, radiological, and manometric data from patients with isolated venous pulsatile tinnitus who had not previously reported headache. All patients underwent lateral sinus stenting in our institution between October 2010 and February 2018.

Results

Forty eight patients, 47 females and one male, were enrolled. The mean age at symptom onset was 36.2 ± 8.7 years and the mean body mass index was 24.0 ± 3.2 kg/m2. Lateral sinus stenosis was evident in 47 patients and a sigmoid diverticulum in one. Fourteen patients experienced headaches after recovering from general anesthesia. All were female, with a mean age of 35.5 ± 9.6 years. Headache persisted for less than 3 days in six patients (42.8%); for 3 days to 3 months in four (28.6%); and for longer than 3 months in four (28.6%). The headaches were located on the same sides as the cranial venous sinus stents in 13 patients (92.9%) and were principally occipital, being oppressive in nine patients (64.3%) and of moderate intensity in seven (50%). Age at onset of pulsatile tinnitus and body mass index were significantly associated with headache ( p < 0.05; t-test).

Conclusion

To the best of our knowledge, this is the first study to describe cranial venous sinus stenting headache in detail. We found that de novo headache developed after cranial venous sinus stenting, and was usually mild to moderate, unilateral, but oppressive; almost one-third of such headaches persisted for more than 3 months. Researchers and clinicians must become familiar with this headache spectrum; further prospective studies are required.

Dural venous sinus stenting for idiopathic intracranial hypertension: An updated review

BACKGROUND

Dural venous sinus stenting (DVSS) is an accepted treatment option in selected patients with medically refractory idiopathic intracranial hypertension and obstructive venous outflow physiology prior to cerebrospinal flow diversion (CSFD) surgery. There are no randomized controlled studies focusing on outcomes and complication rates for dural venous sinus stenting.

PURPOSE

We present the largest comprehensive meta-analysis on DVSS for idiopathic intracranial hypertension (IIH) focusing on success rates, complications, and re-stenting rates to date. We also present a simplified approach to direct retrograde internal jugular vein (IJ) access for DVSS that allows for expedited procedures.

MATERIALS AND METHODS

We performed a retrospective electronic PubMed query of all peer-reviewed articles in the last 15 years between 2003 to 2018. We included all patients who underwent dural venous sinus stenting for a medically refractive IIH and excluded articles without sufficient data on outcomes, complication rates and re-stenting rates. We also evaluated and compared outcomes in patients undergoing direct retrograde IJ access DVSS to traditional transfemoral vein access.

RESULTS

A total of 29 papers and 410 patients who underwent DVSS met criteria for inclusion. DVSS was associated with high technical success [99.5%], low rates of repeated procedure [10%], and low major complication rates [1.5%].

CONCLUSION

Our retrospective comprehensive review of DVSS for medically refractory IIH suggests that stenting in appropriately chosen patients is associated with low complication rates, high technical success, and low repeat procedure rates.

Recommendations for the selection and treatment of patients with idiopathic intracranial hypertension for venous sinus stenting

INTRODUCTION

Although venous sinus stenting (VSS) has emerged as a promising treatment option for patients with idiopathic intracranial hypertension (IIH) and associated venous sinus stenosis, there is considerable ambiguity regarding patient selection criteria, treatment protocols, and management strategies.

METHODS

An extensive literature review was performed to identify all reports of VSS in patients with IIH using PubMed. Recommendations for the selection and treatment of patients with IIH with VSS are outlined as determined based on author opinion from supporting studies. Due to the lack of randomized trials and few published prospective studies, standard grading scales for recommendations and level of evidence are not fully applicable and therefore a revised grading scale has been provided for recommendations.

RESULTS

The literature review identified a total of eight systematic reviews or meta-analyses and 29 published patient series on VSS. Recommendations for patient selection for diagnostic catheter angiography, angiography procedural considerations, stenting procedural considerations, and retreatment are provided based on the literature. Recommendations that were considered strong included: performance of venous sinus manometry to assess candidacy for treatment prior to stenting; administration of antiplatelet agents prior to stenting and for a follow-up period of at least 3-6 months; performance of post-stenting manometry to confirm resolution of pressure gradient; and performance of repeat angiography and manometry on patients with recurrence of symptoms after resolution with stenting to evaluate for recurrent stenosis.

CONCLUSION

VSS for patients with IIH with venous sinus stenosis is now an established and effective treatment option. These recommendations have been provided, based on a summative review of the available published literature, to assist in standardizing care for patients with IIH undergoing VSS.

Unexpected occlusion of the contralateral transverse sinus after stenting for idiopathic intracranial hypertension

A woman in her thirties with intracranial hypertension underwent stenting of the right transverse-sigmoid (TS) junction with resolution of the pressure gradient. Due to persisting symptoms at follow-up, she underwent a repeat study showing a patent right TS stent but the non-dominant left transverse sinus, patent on initial studies, was now completely occluded. According to the positive feedback loop hypothesis, stenting of the right transverse sinus should have resulted in a reduction in intracranial pressures (confirmed by post-stenting lumbar puncture), but also an increase in left transverse sinus diameter, opposed to the occlusion seen on venography. This unexpected finding can be explained by the positive feedback loop hypothesis if a revision is made accounting for intramural venous pressures as an opposing force of venous sinus stenosis, as venous outflow obstruction in the dominant venous sinus pathway provided an increased intramural venous pressure in the non-dominant sinus facilitating patency against extramural pressures.

Venous sinus stenting lowers the intracranial pressure in patients with idiopathic intracranial hypertension

AIMS

We report the cerebrospinal fluid opening pressure (CSF-OP) measurements obtained before and after venous sinus stenting (VSS) in 50 patients with idiopathic intracranial hypertension.

METHODS

The CSF-OP was measured with a spinal tap 3 months before and 3 months after treatment. All data were prospectively collected and included patient demographics, weight (kg), body mass index (BMI), acetazolamide daily dosage (mg), procedural details, complications, venous sinus pressures (mm Hg), trans-stenotic pressure gradient (mm Hg), transverse sinus symmetry, and type of venous sinus stenosis.

RESULTS

The average pretreatment CSF-OP was 37 cm H₂O (range 25-77) and the average post-treatment CSF-OP was 20.2 cm H₂O (range 10-36), with an average reduction of 16.8 cm H₂O (P<0.01). The post-treatment CSF-OP was less than 25 cm H₂O in 40/50 patients. The average acetazolamide daily dose decreased from 950 mg to 300 mg at the time of 3-month follow-up (P<0.01). No patient required an increase in acetazolamide dose 3 months after VSS. The average weight before treatment was 95.4 kg with an average BMI of 35.41. There was an average increase in body weight of 1.1 kg at the 3-month follow-up with an average increase in BMI of 0.35 (P=0.03).

CONCLUSIONS

We provide evidence that there is a significant decrease in CSF-OP in patients with idiopathic intracranial hypertension 3 months after VSS, independent of acetazolamide usage or weight loss.