Venous sinus stenting for idiopathic intracranial hypertension: a systematic review and meta-analysis

Adjunctive venous sinus stenting in transvenous embolization of vein of Galen malformations

BACKGROUND

Vein of Galen malformations are congenital arteriovenous malformations primarily treated by endovascular embolization via transarterial or transvenous approaches. transvenous embolization can be utilized to close the malformation but may be difficult in patients with venous stenosis or blockages, which drive venous hypertension and lead to significant neurologic consequences. Here, we illustrate the atypical placement of an intracranial venous sinus stent to improve outflow after transvenous embolization in pediatric patients with the vein of Galen malformation.

METHODS

A retrospective review of clinical databases at two high-volume endovascular centers from January 2018 to March 2023 identified all vein of Galen malformation patients who received a venous sinus stent during transvenous embolization. Clinical data, imaging, angioarchitecture, operative details, postoperative management, and follow-up were reviewed.

RESULTS

Three patients presented for transvenous embolization after multiple staged transarterial embolizations of their vein of Galen malformation. Transvenous access was complicated by lateral sinus stenosis, which was temporarily relieved by balloon angioplasty. After transvenous embolization by pressure cooker technique, the dural sinuses were stented using the existing venous guide catheter. Venous angiography demonstrated improved flow across the stenosed areas and post-embolization angiography demonstrated normalized venous drainage with widely patent stents. One patient experienced postoperative oculomotor nerve palsy unrelated to the stent placement. All patients demonstrated a complete cure of their vein of Galen malformations with patent venous sinus stents on follow-up.

CONCLUSION

In patients with the vein of Galen malformation and venous hypertension receiving transvenous embolization, venous sinus stenting may be a safe and effective option to reduce aberrant cortical venous drainage and improve normal outflow. Further studies are warranted to investigate its benefit in high-flow vascular malformations.

The correlation between intracranial pressure and venous sinus pressures changes after venous sinus stenting

BACKGROUND

The pathophysiology of idiopathic intracranial hypertension (IIH) and other cerebral venous outflow disorders (CVD) has largely been unexplored. While a correlation between venous sinus pressure and opening pressure (OP) has been previously noted, there are limited data on this relationship in patients with prior venous sinus stenting (VSS).

METHODS

A single center retrospective chart review was conducted on CVD patients who underwent diagnostic cerebral venography with manometry followed immediately by lateral decubitus lumbar puncture, from 2016 to 2024.

RESULTS

206 patients underwent 216 total procedures and were included. Among all patients, there was a moderate nearly one-to-one correlation between OP and torcular or superior sagittal sinus (SSS) pressures. Thirty-two patients underwent testing after having undergone VSS. Patients with previous VSS showed a significantly altered relationship between venous pressures and OP, whereby as venous sinus pressures increased, OP increased more gradually in previously stented patients compared with non-stented patients. For example, when OP was fixed at 21 mm Hg and body mass index at 30 kg/m2, predicted mean SSS pressure was 19.47 mm Hg in non-stented patients versus 16.91 mm Hg in stented patients.

CONCLUSION

This study confirmed a strong relationship between OP and venous sinus pressure in CVD patients. However, patients with previous VSS demonstrated an altered relationship with higher CSF pressures relative to venous pressures compared with naïve patients. This finding may have important clinical implications in the management of IIH patients.

Reconstructive treatment using stent placement for type IIa+b lateral sinus dural arteriovenous fistulas complicated with sinus occlusion

BACKGROUND

Cognard type IIa+b dural arteriovenous fistulas (DAVFs) in the lateral sinuses are often complicated with venous sinus obstruction and accompanied by clinical symptoms and a risk of hemorrhage. The purpose of this study was to assess venous sinus stenting as a viable alternative treatment in complex lateral sinus DAVFs and examine its efficacy and safety.

METHODS

We retrospectively examined patients diagnosed with type IIa+b DAVF in the transverse or sigmoid sinus with associated venous sinus occlusion who were treated via stent placement between April 2017 and June 2019.

RESULTS

Six patients were included in this study. Three patients had DAVFs in both the transverse and sigmoid sinuses, two in the transverse sinus and confluence of sinuses, and one in the transverse sinus. The most common symptoms were headache, dizziness, and limb weakness. At the last follow-up, three patients had significant improvement, and three were asymptomatic. Angiograms performed immediately after the surgery showed restoration of the anterograde venous drainage in all patients. According to the follow-up angiography results, two DAVFs were completely obliterated, and four remained as stable type I DAVFs. Most patients had satisfactory venous sinus drainage, except one who had in-stent stenosis.

CONCLUSIONS

Stent placement can restore sinus patency, improve clinical symptoms, and decrease intracranial hemorrhage risk. This approach may be an effective option for treating type IIa+b lateral DAVFs complicated by sinus occlusion.

Venous sinus stenting versus ventriculoperitoneal shunting: comparing clinical outcomes for idiopathic intracranial hypertension

BACKGROUND

Venous sinus stenting (VSS) has been shown to reduce intracranial venous pressures and improve symptoms in patients with idiopathic intracranial hypertension (IIH). However, long-term follow-up data are limited, raising concerns about sustained symptom improvement. We aimed to assess long-term outcomes of VSS compared with ventriculoperitoneal shunting (VPS).

METHODS

A retrospective case-control study assessed 87 patients with IIH who met inclusion criteria and underwent either VSS (n=27) or VPS (n=60) between 2017 and 2022. Descriptive statistics for baseline characteristics and outcomes were calculated, followed by multivariate logistic regression to identify factors associated with headache recurrence.

RESULTS

Baseline characteristics were similar between VSS and VPS groups, including age (p=0.58), sex (p=0.74), body mass index (p=0.47), and preoperative lumbar puncture opening pressure (p=0.62). Preoperative symptoms of headaches (p=0.42), papilledema (p=0.35), and pulsatile tinnitus (p=0.56) were also similar. Initial headache improvement was comparable (96% vs 91%, p=0.42). However, headache recurrence was less common in the VSS group (31% vs 60%, p=0.015) at the last follow-up, averaging over 1 year. Multivariate analysis showed VSS was independently associated with reduced odds of headache recurrence (OR 0.24, p=0.015). Longer follow-up was associated with increased odds of headache recurrence in both groups (OR 1.01, p=0.032).

CONCLUSION

VSS was independently associated with reduced odds of headache recurrence compared with VPS in multivariate analysis. Longer follow-up was significantly associated with headache recurrence in both groups. This suggests that VSS may lead to better outcomes for continued headache relief, but headache recurrence may increase with longer follow-up regardless of treatment modality.

Outcomes of Pulsatile Tinnitus After Cerebral Venous Sinus Stenting: Systematic Review and Pooled Analysis of 616 Patients

BACKGROUND

Pulsatile tinnitus (PT) is a debilitating condition with substantial morbidity related to quality of life. Cerebral venous sinus stenosis has recently emerged as a noninfrequent cause of PT, either in the setting of concurrent idiopathic intracranial hypertension (IIH) or due to primary venous stenosis. Venous sinus stenting (VSS) is an endovascular technique that can be used to treat venous stenosis. However, it is unclear if outcomes are different between patients with primary venogenic PT and IIH associated PT.

METHODS

A systematic literature review and pooled analysis was completed to evaluate the clinical outcomes of PT in patients undergoing cerebral VSS. Outcome measures included: Improved PT, complete resolution of PT, and PT recurrence at follow-up. Subgroup analysis between patients with IIH and primary PT was completed.

RESULTS

In total, 28 studies were identified with 616 patients. The proportion of improved PT symptoms after VSS had an overall pooled rate of 91.7% (confidence interval [CI]:88.1%-95.2%; I2 = 65%) and no difference between subgroups (P = 0.12). Complete resolution after VSS had an overall pooled rate of 88.6% (CI: 84.0%-93.3%; I2 = 68%) and no significant difference between subgroups (P = 0.35). Recurrent PT after stenting occurred in 6.5% of cases (CI: 1.7%-11.3%; I2 = 62%). Furthermore, subgroup analysis demonstrated that IIH patients had a significantly higher recurrence rate (10.6%; CI: 5.2%-16.1%; I2 = 26%) compared to patients treated with venous stenting for PT as the primary indication (2.0%; CI: 0.8%-4.7%; I2 = 0%) (P < 0.0001).

CONCLUSIONS

Venous stenting in patients with PT results in a substantial decrease and often complete resolution of symptoms. PT is more likely to recur in patients with IIH-associated PT.

Venous sinus stenting under conscious sedation

BACKGROUND

Venous sinus stenting (VSS) is an increasingly performed procedure for the treatment of idiopathic intracranial hypertension (IIH) refractory to medical treatment. VSS is typically performed under general anesthesia.

OBJECTIVE

To present our experience of VSS in patients with IIH performed under conscious sedation.

METHODS

Retrospective review of a prospectively maintained database of all patients with IIH who underwent VSS in a single center between September 2019 and January 2024. The sedation protocol consisted of a remifentanil-based target-controlled infusion. Patients' clinical and radiological data, dosage of anesthesia, procedural characteristics, and outcomes were collected.

RESULTS

Twenty-six patients with IIH underwent venous manometry (VM) and VSS under awake sedation and were included in our study. Patients were predominantly women (24/26) with a median age (IQR) of 33 (13) years. The median (IQR) body mass index was 34 (10) kg/m2. There was no need for general anesthesia conversion. Technical success was achieved in all patients. Median (IQR) follow-up after stenting was 7 (2) months. All patients reported resolution of the pulsatile tinnitus; headaches regressed in 20/24 (83.3%) patients and papilledema improved in 16/20 (80%). Only one non-neurological complication (retroperitoneal hematoma) occurred, without any permanent morbidity or mortality.

CONCLUSION

Our study confirms that performing VM and VSS under conscious sedation is safe and feasible. Conscious sedation is a viable alternative to general anesthesia for managing IIH in these patients.

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.

Progress and recognition of idiopathic intracranial hypertension: A narrative review

BACKGROUND

Idiopathic intracranial hypertension (IIH) mainly affects obese young women, causing elevated intracranial pressure, headaches, and papilledema, risking vision loss and severe headaches. Despite weight loss as the primary treatment, the underlying mechanisms remain unclear. Recent research explores novel therapeutic targets.

AIMS

This review aimed to provide a comprehensive understanding of IIH's pathophysiology and clinical features to inform pathogenesis and improve treatment strategies.

METHODS

Recent publications on IIH were searched and summarized using PubMed, Web of Science, and MEDLINE.

RESULTS

The review highlights potential pathomechanisms and therapeutic advances in IIH.

CONCLUSION

IIH incidence is rising, with growing evidence linking it to metabolic and hormonal disturbances. Early diagnosis and treatment remain challenging.

Back to Bernoulli: a simple formula for trans-stenotic pressure gradients and retrospective estimation of flow rates in cerebral venous disease

BACKGROUND

Venous sinus stenosis can be associated with cerebrovascular disorders. Understanding the role of blood flow disturbances in these disorders is often hampered by the lack of patient-specific flow rates. Our goal was to demonstrate the impact of this by predicting individual flow rates retrospectively from routine manometry and angiography.

METHODS

Ten cases, spanning a range of stenosis severities and pressure gradients, were selected from a cohort of patients who had undergone venous stenting for pulsatile tinnitus. Lumen geometries were digitally segmented from CT venograms. A simplified Bernoulli formula was derived to estimate individual cycle-average flow rates from clinical pressure gradients and minimum lumen cross-section areas. High-fidelity pulsatile computational fluid dynamics (CFD) simulations were performed to compare predictions of flow disturbances using generic versus individual flow rates, and to validate the Bernoulli formula.

RESULTS

Individual flow rates derived from the Bernoulli formula deviated by up to 47% from the assumed generic flow rate, resulting in substantial differences in CFD predictions of post-stenotic flow instabilities. Pressure gradients estimated by the simplified Bernoulli formula were, however, highly predictive of pressure gradients from the full CFD simulations (R2=0.95; slope=0.98, 95% CI 0.88 to 1.09).

CONCLUSIONS

A simple Bernoulli formula can predict CFD-estimated trans-stenotic pressure gradients in realistic venous geometries. As demonstrated here, this may be used to recover individual flow rates from routine-but-invasive clinical measurements; however, it also suggests a simpler path towards non-invasive estimation of trans-stenotic pressure gradients that may avoid some of the challenges associated with 4D flow MRI approaches.

Idiopathic Intracranial Hypertension

Idiopathic intracranial hypertension is defined by headaches and a decline in visual acuity due to increased intracranial pressure. Treatment options historically included weight loss, acetazolamide, and/or cerebrospinal fluid diversion surgery. Recent understanding of the contributions of dural venous sinus hypertension and stenosis has led to venous sinus stenting as a treatment option.

Causes of Pulsatile Tinnitus and Treatment Options

Pulsatile tinnitus (PT) requires detailed workup to evaluate for an underlying structural cause. With advances in neuroimaging, structural venous abnormalities that can cause PT have becoming increasingly recognized. A number of anomalies, including dural arteriovenous fistulas, idiopathic intracranial hypertension, transverse sinus stenosis, sigmoid sinus wall abnormalities, jugular venous anomalies, and hypertrophied emissary veins, have been implicated in flow disruption and turbulence in the vicinity of auditory structures, resulting in PT. Endovascular treatment options, including stenting, coiling, and embolization with liquid agents, have demonstrated high efficacy and safety. These treatments can lead to symptomatic relief in carefully selected cases.

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.

Dynamic internal jugular vein venography: a descriptive study in 89 patients with suspected cerebral venous outflow disorders

BACKGROUND

Internal jugular vein (IJV) stenosis has recently been recognized as a plausible source of symptom etiology in patients with cerebral venous outflow disorders (CVD). Diagnosis and determining surgical candidacy remains difficult due to a poor understanding of IJV physiology and positional symptom exacerbation often reported by these patients.

METHODS

A retrospective single-center chart review was conducted on adult patients who underwent diagnostic cerebral venography with rotational IJ venography from 2022 to 2024. Patients were divided into three groups for further analysis based on symptoms and diagnostic criteria: presumed jugular stenosis, near-healthy venous outflow, and idiopathic intracranial hypertension.

RESULTS

Eighty-nine patients were included in the study. Most commonly, ipsilateral rotation resulted in ipsilateral IJV stenosis and gradient development at C4-6 and contralateral stenosis and gradient appearance in the contralateral IJV at C1, with stenosis and gradient development in bilateral IJVs at C1-3 bilaterally during chin flexion. In all patients, 93.3% developed at least moderate dynamic stenosis of at least one IJV, more than two-thirds (69.7%) developed either severe or occlusive stenosis during rightward and leftward rotation, and 81.8% developed severe or occlusive stenosis with head flexion. Dynamic gradients of at least 4 mmHg were seen in 68.5% of patients, with gradients of at least 8 mmHg in 31.5% and at least 10 mmHg in 12.4%.

CONCLUSION

This study is the first to document dynamic changes in IJV caliber and gradients in different head positions, offering insights into the complex nature of venous outflow and its impact on CVD.

Novel, braided, self-expandable stent designed for the treatment of pulsatile tinnitus caused by intracranial venous stenosis: first-in-human experience and long-term outcomes

BACKGROUND

Pulsatile tinnitus (PT) can be a disabling clinical condition, which may be caused by a sigmoid/transverse sinus stenosis (STSS). Intracranial venous stenting with off-label carotid or peripheral venous stents has been used successfully to treat this condition. We present the results of a cohort of patients presenting with PT treated with a novel, dedicated, braided stent for the endovascular treatment of STSS.

METHODS

Twelve patients presenting with PT and associated STSS were treated at our institution (December 2022-June 2023). All clinical and procedural variables were prospectively collected. We used the Tinnitus Function Index (TFI) and the Tinnitus Handicap Inventory (THI) scores to assess the impact of PT on quality of life before and after the treatment (mean follow-up: 10.3 months).

RESULTS

Twelve women (mean age: 44±16.5 years) presenting with PT and STSS were treated. Mean pretreatment TFI/THI scores were 78.8/77. The BosStent was successfully deployed in all patients. We experienced no intraprocedural/postoperative complications. Intra-stent angioplasty was performed in three cases. All patients reported a complete resolution of PT symptoms within 1 month and remained stable and PT-free at the last follow-up (mean posttreatment TFI/THI score: 7.1/5, p<0001).

CONCLUSIONS

The BosStent was successfully used in a cohort of patients with PT without any intraprocedural complications. All the patients experienced a complete resolution of PT symptoms after 1 month, which was stable during the follow-up period. Further studies with larger populations will be necessary to investigate the safety and effectiveness of this novel stent for the treatment of PT with STSS.

A Pathophysiological Approach to Spontaneous Orbital Meningoceles: Case Report and Systematic Review

BACKGROUND

Spontaneous orbital cephaloceles are a rare condition. The purpose of this study is to provide a description of a clinical case and to carry out a systematic literature review.

METHODS

A systematic review of the English literature published on the Pubmed, Scopus, and Web of Science databases was conducted, according to the PRISMA recommendations.

RESULTS

A 6-year-old patient was admitted for right otomastoiditis and thrombosis of the sigmoid and transverse sinuses, as well as the proximal portion of the internal jugular vein. Radiological examinations revealed a left orbital mass (22 × 14 mm) compatible with asymptomatic orbital meningocele (MC) herniated from the superior orbital fissure (SOF). The child underwent a right mastoidectomy. After the development of symptoms and signs of intracranial hypertension (ICH), endovascular thrombectomy and transverse sinus stenting were performed, with improvement of the clinical conditions and reduction of the orbital MC. The systematic literature review encompassed 29 publications on 43 patients with spontaneous orbital MC. In the majority of cases, surgery was the preferred treatment.

CONCLUSIONS

The present case report and systematic review highlight the importance of ICH investigation and a pathophysiological-oriented treatment approach. The experiences described in the literature are limited, making the collection of additional data paramount.

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.

Stenting for Venous Sinus Stenosis in Patients With Idiopathic Intracranial Hypertension: An Updated Systematic Review and Meta-Analysis of the Literature

BACKGROUND AND OBJECTIVES

Although venous sinus stenting (VSS) improves cerebrospinal fluid reabsorption and decreases intracranial pressure in patients with idiopathic intracranial hypertension (IIH), the underlying pathophysiology of IIH is not well understood. We present a review and meta-analysis of the literature on VSS for IIH treatment, focusing on the rates of restenosis and symptom recurrence.

METHODS

We performed a systematic review of PubMed and Embase databases between January 1, 2011, and December 31, 2021. Articles including ≥5 patients with IIH and venous sinus stenosis treated with VSS and post-treatment rates of restenosis (de novo stenosis at a different anatomic location along the dural sinuses or restenosis within or adjacent to the stent) were selected. Demographic, procedural, and outcomes data were collected and analyzed. Mean values for variables collected were pooled, and a mean value was calculated with a 95% CI.

RESULTS

Twenty-four articles were included, comprising 694 patients and 781 VSS cases. The mean age was 33.9 (CI, 31.5-36.2) years. The mean body mass index was 35.3 (CI, 32.9-37.7) kg/m 2 . Before VSS, 98.8% (CI, 96.8%-100.0%) of patients experienced headaches, 87.7% (CI, 80.6%-95.5%) had visual acuity issues, 78.7% (CI, 69.9%-88.5%) had papilledema, 58.3% (CI, 46.0%-73.9%) had tinnitus, and 98.8% (96.4%-100.0%) had symptoms refractory to previous therapies. After VSS, 77.7% (CI, 71.1%-84.95%) experienced symptom improvement and 22.3% (CI, 15.1%-29.0%) had persistent or worsened symptoms. Pooled restenosis rate was 17.7% (CI, 14.9%-20.9%).

CONCLUSION

VSS is effective in alleviating IIH signs and symptoms, but the associated high rates of restenosis and persistent symptoms highlight the need for further investigation of this procedure and other adjunctive treatments for IIH.

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.

Redefining treatment expectations: exploring mid- and long-term outcomes of venous sinus stenting in idiopathic intracranial hypertension

BACKGROUND

Venous sinus stenting (VSS) is recognized as a safe and effective intervention for medically-refractory idiopathic intracranial hypertension (IIH). However, its long-term efficacy remains uncertain.

METHODS

This retrospective review analyzed a single-center database of adult patients with severe, medically-refractory IIH, who underwent VSS and had minimum 3-month follow-up (FU). Patients were divided into three groups based on post-stenting symptom trajectories: group 1 (sustained improvement without relapse), group 2 (temporary improvement with relapse), and group 3 (no improvement).

RESULTS

Of 178 patients undergoing VSS, the majority were female (94%), with a median opening pressure (OP) of 31 cm H2O and trans-stenosis gradient of 14 mm Hg. Of these, 153 (86%) received transverse sinus (TS) stenting, and 19 (11%) underwent concurrent TS and superior sagittal sinus stenting. At a mean FU of 166 days, 53 patients (30%) showed long-term improvement without relapse (group 1). Symptomatic recurrence was noted in 101 patients (57%; group 2) within a mean FU of 390 days. Despite recurrent headache and tinnitus, the average OP reduction was 9.6 cm H2O on repeat lumbar puncture, with 75% showing papilledema improvement or resolution post-VSS. Only 17% required further surgical intervention.

CONCLUSIONS

The most common clinical outcome post-VSS in IIH patients is initial symptomatic improvement followed by symptom recurrence in about 60% at a mean of 274 days, despite a consistent intracranial pressure reduction. These findings can guide physicians in setting realistic expectations with patients regarding VSS outcomes.

Neurovascular Interventions for Neurotrauma: From Treatment of Injured Vessels to Treatment of the Injured Brain?

Traumatic brain injury is often associated with a direct or secondary neurovascular pathology. In this review, we present recent advancements in endovascular neurosurgery that enable accurate and effective vessel reconstruction with emphasis on its role in early diagnosis, the expanding use of flow diversion in pseudoaneurysms, and traumatic arteriovenous fistulas. In addition, future directions in which catheter-based interventions could potentially affect traumatic brain injury are described: targeting blood brain barrier integrity using the advantages of intra-arterial drug delivery of blood brain barrier stabilizers to prevent secondary brain edema, exploring the impact of endovascular venous access as a means to modulate venous outflow in an attempt to reduce intracranial pressure and augment brain perfusion, applying selective intra-arterial hypothermia as a neuroprotection method mitigating some of the risks conferred by systemic cooling, trans-vessel wall delivery of regenerative therapy agents, and shifting attention using multimodal neuromonitoring to post-traumatic vasospasm to further characterize the role it plays in secondary brain injury. Thus, we believe that the potential of endovascular tools can be expanded because they enable access to the "highways" governing perfusion and flow and call for further research focused on exploring these routes because it may contribute to novel endovascular approaches currently used for treating injured vessels, harnessing them for treatment of the injured brain.

Assessment of Reversibility of Transverse Venous Sinus Stenosis in Patients With Papilledema

BACKGROUND

Bilateral transverse venous sinus stenosis (TVSS) or stenosis of a dominant venous sinus has been found to be very sensitive radiological findings in patients with intracranial hypertension (IH), yet there is still an ongoing debate whether they constitute reversible or permanent phenomena. Thus, the purpose of this study was to investigate the reversibility of TVSS in patients with IH, including conservatively treated patients with signs of IH as defined by the presence of papilledema.

METHODS

This was a retrospective chart review of all patients diagnosed with IH between 2016 and 2022, assessed from 2 tertiary university-affiliated neuro-ophthalmology practices. Inclusion criteria were the presence of papilledema, as quantified by optical coherence tomography, and bilateral TVSS, which is considered typical of IH on neuroimaging. During follow-up, included patients must have had confirmation of papilledema resolution as well as subsequent neuroimaging after conservative treatment or cerebrospinal fluid flow diversion. Patients with dural sinus vein thrombosis or intrinsic stenosis from sinus trabeculations or significant arachnoid granulations were excluded from the study. Either CT venography or MRI/MR venography was reviewed by a fellowship-trained neuroradiologist, and the degree of stenosis was scored through the combined conduit score (CCS), as described by Farb et al. The primary outcome was to assess TVSS changes after resolution or improvement of papilledema.

RESULTS

From 435 patients, we identified a subset of 10 who satisfied all inclusion criteria. Our cohort comprised entirely women with a median age of 29.5 years and a median BMI of 32.5 kg/m2. Treatment consisted of acetazolamide in 7 patients, of which 1 had additional topiramate and 2 underwent cerebrospinal fluid flow diversion. Furthermore, 6 patients demonstrated significant weight loss during follow-up. For the primary outcome, 5 of 10 patients exhibited no appreciable TVSS change, and 5 patients demonstrated significant improvement in TVSS, of which 4 received conservative treatment only. Papilledema resolution or improvement was statistically significantly associated with increasing average CCS, TVSS diameter, and grade.

CONCLUSIONS

We were able to demonstrate that TVSS can be both irreversible and reversible in patients with resolved papilledema. The finding of TVSS reversibility from conservative treatment alone is novel and has important implications to optimize patient care. Future studies should work to identify factors associated with irreversible TVSS for subsequent targeted intervention and prevention.

Intensive care unit admission is not necessary after venous sinus stenting

BACKGROUND

Venous sinus stenting (VSS) has emerged as a safe and effective treatment option for idiopathic intracranial hypertension. Many physicians routinely admit patients to the intensive care unit (ICU) for close monitoring, but little data exists on whether this is necessary.

METHODS

Electronic medical records of consecutive patients who underwent VSS by the senior author from 2016 to 2022 at a single center were reviewed.

RESULTS

214 patients were included. The mean (SD) age was 35.5 (11.6) and 196 (91.6%) patients were female. A total of 166 (77.6%) patients underwent transverse sinus stenting alone; 9 (4.2%) underwent superior sagittal sinus (SSS) stenting alone, 37 (17.3) concomitant transverse and SSS stenting, and 2 (0.9%) underwent stenting at alternate sites. All patients were planned admission to the regular ward (27.6%) or day hospital (72.4%). Twenty (9.3%) patients were discharged to home the same day as the procedure and 182 (85%) patients were discharged the following day. Major periprocedural complications were identified in 2 (0.93%) patients and minor complications were identified in 16 (7.4%). Only one patient with a subdural hematoma identified in the post-anesthesia care unit (PACU) had care escalated to the ICU. No severe complications were identified after the PACU stay. During the next 48 hours after discharge, 4 (1.9%) patients returned to any emergency room to be evaluated without requiring readmission.

CONCLUSION

Routine ICU admission following uncomplicated VSS is unnecessary. Overnight admission to a low-acuity ward, or even same-day discharge in select patients, appears to be a safe and cost-effective strategy.

Cerebral venous sinus stenting and jugular bulb embolization for pulsatile tinnitus: A case report

Background

Pulsatile tinnitus (PT) is a rare form of tinnitus that aligns with the heartbeat. It is typically brought on by lesions with significant vascularity, which produce aberrant sound conduction and increase the risk of mental health issues and hearing loss. Venous PT is more prevalent than arterial PT. Open procedures or interventional procedures can be used to treat PT. We present here a case of PT caused by venous luminal stenosis combined with jugular bulb (JB) malformation, which was improved by stenting and JB embolization.

Case presentation

A 59-year-old woman presented with long-term tinnitus consistent with heart rhythm and hearing loss, accompanied by anxiety, insomnia, and depression. The results of brain MRV, CT, and DSA showed stenosis of the right sigmoid sinus and high jugular bulb (JB) with dehiscence of the JB wall. The patient saw a significant improvement in PT symptoms following sigmoid sinus stenting and spring coil embolization of the high JB, following the diagnosis of PT. The patient had no PT recurrence for the course of the 31-month follow-up period.

Conclusion

In the present PT case, there was a simultaneous onset of the right sigmoid sinus stenosis and the high JB with the JB wall abnormalities. Sigmoid sinus stenting and spring coil embolization of high JB may be a treatment for the PT, but the prevention of post-stenting complications is still an issue that requires great attention and needs further study.

Endovascular Brain-Computer Interfaces in Poststroke Paralysis

Stroke is a leading cause of paralysis, most frequently affecting the upper limbs and vocal folds. Despite recent advances in care, stroke recovery invariably reaches a plateau, after which there are permanent neurological impairments. Implantable brain-computer interface devices offer the potential to bypass permanent neurological lesions. They function by (1) recording neural activity, (2) decoding the neural signal occurring in response to volitional motor intentions, and (3) generating digital control signals that may be used to control external devices. While brain-computer interface technology has the potential to revolutionize neurological care, clinical translation has been limited. Endovascular arrays present a novel form of minimally invasive brain-computer interface devices that have been deployed in human subjects during early feasibility studies. This article provides an overview of endovascular brain-computer interface devices and critically evaluates the patient with stroke as an implant candidate. Future opportunities are mapped, along with the challenges arising when decoding neural activity following infarction. Limitations arise when considering intracerebral hemorrhage and motor cortex lesions; however, future directions are outlined that aim to address these challenges.

Intensive mannitol slow infusion post-stenting may attenuate stenting-related early adverse effects in patients with cerebral venous sinus stenosis

AIMS

To analyze intensive slow mannitol poststenting on attenuating stenting-related early adverse effects in cerebral venous sinus stenosis (CVSS).

METHODS

This real-world study enrolled subacute or chronic CVSS patients from January 2017 through March 2022 and divided them into DSA only and stenting post-DSA groups. The later group was subdivided into control (without extra mannitol use) and intensive slow mannitol subgroup (immediate extra mannitol 250-500 mL, 2 mL/min infusion post-stenting) after signed informed consent. All data were compared.

RESULTS

A total of 95 eligible patients entered into final analysis, in which 37 cases underwent DSA only and 58 cases underwent stenting post-DSA. Finally, 28 patients were entered into intensive slow mannitol subgroup and 30 in control. Stenting group vs. DSA group, HIT-6 scores and WBC counts were higher in the former (both p < 0.001). Intensive slow mannitol subgroup vs. control on the third day post-stenting, a statistically significant reductions were noticed in the former on WBC counts (6.19 ± 1.86 × 109 /L vs. 9.59 ± 2.05 × 109 /L); HIT-6 scores (degree of headache) (40.00 (38.00-40.00) vs. 49.00 (41.75-55.25)) and brain edema surrounding the stent on CT maps (17.86% vs.96.67%), all p < 0.001.

CONCLUSIONS

Stenting-related severe headache, inflammatory biomarkers elevation, and brain edema aggravation can be attenuated by intensive slow mannitol infusion.

Zilver stent versus Carotid Wallstent for endovascular treatment of idiopathic intracranial hypertension

BACKGROUND

Venous sinus stenting (VSS) is a promising treatment option for medically refractory idiopathic intracranial hypertension (IIH). There are no published studies comparing the performance of different types of stents employed in VSS procedures. In this study we aimed to compare the safety and efficacy outcomes of the Zilver 518 (Cook Medical, Bloomington, Indiana, USA) and the Carotid Wallstent (Boston Scientific, Marlborough, Massachusetts, USA) devices.

METHODS

Records of patients with IIH who underwent VSS between January 2015 and February 2022 at a single referral center were retrospectively reviewed. Patients treated with the Zilver stent or Carotid Wallstent were included in the study. Stent model and size data, pre- and post-treatment pressure gradients, technical and safety outcomes, and pre- and post- stenting papilledema, headache, and tinnitus severity were collected. The χ2 and Fisher-Freeman-Halton tests were used for categorical data and the Student's t-test and Mann-Whitney U test were employed to examine the differences in non-categorical variables.

RESULTS

A total of 81 procedures (28 (34.5%) with the Zilver stent and 53 (65.5%) with the Carotid Wallstent) were performed in 76 patients. The mean procedure time was significantly shorter with the Zilver stent (22.56±10.2 vs 33.9±15 min, p=0.001). The papilledema improvement and resolution rates did not significantly differ between groups (94.7% vs 94.5%, p>0.99 for improvement; 78.9% vs 67.5%, p=0.37 for resolution). The tinnitus improvement and resolution rates in the Zilver stent group were significantly higher than those of the Carotid Wallstent group (100% vs 78.9%, p=0.041; 90% vs 63.1%, p=0.03, respectively). Additionally, the Zilver stent provided a significantly higher rate of headache resolution and improvement than the Carotid Wallstent (84.6% vs 27.6%, p=0.001 for resolution; 92.3% vs 72.3%, p=0.043 for improvement). One patient from the Carotid Wallstent group underwent re-stenting due to in-stent stenosis and refractory papilledema. No significant in-stent stenosis was observed in the Zilver stent group.

CONCLUSION

Stent choice may affect VSS outcomes. The Zilver stent provided better clinical outcomes than the Carotid Wallstent, with significantly shorter procedure times. Larger studies are needed to determine the efficacy of available venous stents for IIH.

Transverse Venous Sinus Stenosis in Patients With Nasal Cerebrospinal Fluid Leak and Idiopathic Intracranial Hypertension

OBJECTIVE

Spontaneous nasal cerebrospinal fluid (CSF) leaks are frequently linked to idiopathic intracranial hypertension (IIH). The objectives of our study were: (1) to determine the rate of transverse venous sinus stenosis (TVSS) in patients with spontaneous nasal CSF leak and in patients with IIH without CSF (controls), and (2) to study the correlation between spontaneous nasal CSF leak and brain imaging features.

STUDY DESIGN

A multicenter retrospective case-control study.

SETTING

Six French tertiary hospitals.

METHODS

Patients with spontaneous nasal CSF leaks and patients with IIH without nasal CSF leaks (controls) were included. The transverse venous sinus patency was analyzed by magnetic resonance imaging to identify possible stenosis or hypoplasia.

RESULTS

Thirty-two patients with spontaneous nasal CSF leaks and 32 controls were included. TVSS was significantly more frequent in patients with spontaneous nasal CSF leaks than in controls (p = .029). Univariate analysis indicated that TVSS (odds ratio, OR: 4.2; 95% confidence interval, CI [1.352-14.915]; p = .017) and arachnoid granulations (OR: 3; 95% CI [1.065-8.994]; p = .042) were risk factors for spontaneous nasal CSF leak. In multivariate analysis, TVSS and arachnoid granulations were independent risk factors of nasal CSF leak (OR: 5.577, 95% CI [1.485-25.837], p = .016; and OR: 4.35, 95% CI [1.234-17.756], p = .029, respectively).

CONCLUSION

This multicenter case-control study shows that TVSS is an independent risk factor for CSF leak in patients with IIH. Stenosis management by interventional radiology may be proposed postoperatively to increase the success of IIH surgical treatment or preoperatively to reduce the need for surgery.

Cranial decompression and expansion surgery for the treatment of refractory idiopathic intracranial hypertension: case report and systematic review

OBJECTIVE

The purpose of this study is to systematically review the literature on the clinical outcomes following different surgical techniques in patients with refractory idiopathic intracranial hypertension (IIH).

BACKGROUND

IIH is a condition characterised by increased cranial pressure (ICP) in the absence of an intracranial lesion that does not adequately respond to different medical and surgical therapies. Cranial decompression or expansion surgeries are a last resort therapy for patients with refractory IIH.

METHODS

A systematic literature search of the databases of PubMed, Embase and Medline from inception to 2019 was performed. Searches were limited to the English language and to clinical studies. Studies were included if clinical outcomes following different cranial decompression or expansion techniques were reported. We also add one case of our own experience with performing a bilateral frontoparietal expansion craniotomy and subtemporal craniectomy.

RESULTS

Five manuscripts, describing 38 procedures, met the inclusion criteria. Thirty-one patients were female (82%). The mean age was 26.2 years. The techniques studied included subtemporal craniectomy (27/38, 71%), internal cranial expansion (10/38, 26%), and cranial morcellation decompression (1/38, 3%). Thirty-five patients presented with headaches of which 17 noted postoperative improvement or resolution (49%). Visual deficits were documented in 30 patients and 25 reported postoperative improvement (83%). Papilledema disappeared in 23 of 32 patients with this sign at presentation (72%). In our patient, symptoms completely resolved postoperatively and a 6% increase in intracranial volume was measured.

CONCLUSIONS

Cranial vault decompression or expansion surgeries may be an effective last resort therapy for patients with refractory IIH. These surgeries expand the intracranial volume, and thus may normalise ICP, leading to clinical improvement.

ACR Appropriateness Criteria® Tinnitus: 2023 Update

Tinnitus is abnormal perception of sound and has many subtypes. Clinical evaluation, audiometry, and otoscopy should be performed before ordering any imaging, as the choice of imaging will depend on various factors. Type of tinnitus (pulsatile or nonpulsatile) and otoscopy findings of a vascular retrotympanic lesion are key determinants to guide the choice of imaging studies. High-resolution CT temporal bone is an excellent tool to detect glomus tumors, abnormal course of vessels, and some other abnormalities when a vascular retrotympanic lesion is seen on otoscopy. CTA or a combination of MR and MRA/MRV are used to evaluate arterial or venous abnormalities like dural arteriovenous fistula, arteriovenous malformation, carotid stenosis, dural sinus stenosis, and bony abnormalities like sigmoid sinus wall abnormalities in cases of pulsatile tinnitus without a vascular retrotympanic lesion. MR of the brain is excellent in detecting mass lesions such as vestibular schwannomas in cases of unilateral nonpulsatile tinnitus. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision process support the systematic analysis of the medical literature from peer reviewed journals. Established methodology principles such as Grading of Recommendations Assessment, Development, and Evaluation or GRADE are adapted to evaluate the evidence. The RAND/UCLA Appropriateness Method User Manual provides the methodology to determine the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where peer reviewed literature is lacking or equivocal, experts may be the primary evidentiary source available to formulate a recommendation.

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.

Venous sinus stenting for the treatment of acute blindness in a patient with idiopathic intracranial hypertension

We present a case of acute onset of blindness treated with venous sinus stenting in the hyperacute period (24-48 h). The patient had not been diagnosed previously with idiopathic intracranial hypertension and presented at an outside facility with a short history of headache, nausea, vomiting and visual deficits. Initial management included lumbar punctures for pressure relief. Unfortunately, the patient's condition deteriorated and she experienced the rapid onset of blindness. Within 24-48 h of blindness onset, she was transferred to our institution for emergent endovascular stenting of the venous sinuses. The intervention resulted in improvement of symptoms and recovery of visual acuity over a short-term follow-up period.

A descriptive study of venous pressures and gradients while awake and both pre- and post-stent under anesthesia in patients with idiopathic intracranial hypertension

BACKGROUND

This study aims to explore factors that affect venous sinus pressures and associated gradients while awake and under general anesthesia (GA) both before and after venous sinus stenting (VSS) in patients with idiopathic intracranial hypertension (IIH).

METHODS

A retrospective analysis was performed examining pressures and gradients in patients with IIH having undergone awake venography followed by VSS under GA.

RESULTS

174 patients were included. Compared with awake, GA superior sagittal sinus (SSS) pressures were 2.6 mmHg lower (p=0.01) resulting in a total cranial gradient reduction of 2.5 mmHg (p=0.002). The transverse-sigmoid gradient, the most commonly stented segment, did not differ under the two conditions (p=0.30). Regression analyses demonstrated that body mass index, gender, blood pressure, and end-tidal carbon dioxide content significantly affected venous pressures (all p<0.05). After stenting, mean total cranial gradients decreased by 13.2 mmHg while skull base gradients increased by 0.8 mmHg. Stenting resulted in an 84% mean reduction in the target gradient and a mean decrease in SSS pressures by 78% of the target gradient. When cardiopulmonary and anesthetic factors were optimized, GA had a limited effect on the target gradient in most patients (p=0.88).

CONCLUSIONS

This study is the largest series to date to report on cerebral venous pressure measurements and gradients recorded while awake and under GA both before and after VSS for IIH. In a well-controlled cardiorespiratory and anesthetic setting, GA venography may provide information that is not substantially inequivalent to that obtained while awake.

Blood Flow Velocity: a Decision Tool for Stenting Indication in Venous Pulsatile Tinnitus

BACKGROUND AND PURPOSE

Lateral sinus stenosis is the most common cause of venous pulsatile tinnitus (VPT). Stenting is an effective treatment after demonstration of a trans-stenotic pressure gradient; however, pressure measurement has many technical limitations. In 2018, a study showed that a combined approach with intravascular velocity measurement could be effective in identifying most appropriate candidates for stenting. The aim of the present study was to evaluate a new strategy using this biomarker for the indication of stenting even without a significant pressure gradient.

MATERIAL AND METHODS

Consecutive patients with disabling VPT were included from 2016 to 2019 and analyzed retrospectively. Intrasinusal pressures were measured and blood flow velocities (with a dual-sensor guidewire) were used for the indication of stenting independent of the pressure gradient. We evaluated the clinical outcome after stenting based on this new biomarker.

RESULTS

A total of 41 patients were treated according to this strategy. At last follow-up (mean = 30.2 months), 32/33 patients (97%) treated by stenting showed complete resolution or a significant decrease in VPT intensity. The use of velocity as the threshold for indicating stenting identified 8 patients (24%) missed by the pressure gradient. Their clinical outcome after stenting was excellent and no complications occurred.

CONCLUSION

Measurement of sinus blood flow velocity provides a hemodynamic explanation of disease and may be a better tool than pressure gradient for the indication of stenting in VPT.

The protective role of GLP-1 in neuro-ophthalmology

Despite recent advancements in the field of neuro-ophthalmology, the rising rates of neurological and ophthalmological conditions, mismatches between supply and demand of clinicians, and an aging population underscore the urgent need to explore new therapeutic approaches within the field. Glucagon-like peptide 1 receptor agonists (GLP-1RAs), traditionally used in the treatment of type 2 diabetes, are becoming increasingly appreciated for their diverse applications. Recently, GLP-1RAs have been approved for the treatment of obesity and recognized for their cardioprotective effects. Emerging evidence indicates some GLP-1RAs can cross the blood-brain barrier and may have neuroprotective effects. Therefore, this article aims to review the literature on the neurologic and neuro-ophthalmic role of glucagon-like peptide 1 (GLP-1). This article describes GLP-1 peptide characteristics and the mechanisms mediating its known role in increasing insulin, decreasing glucagon, delaying gastric emptying, and promoting satiety. This article identifies the sources and targets of GLP-1 in the brain and review the mechanisms which mediate its neuroprotective effects, as well as implications for Alzheimer's disease (AD) and Parkinson's disease (PD). Furthermore, the preclinical works which unravel the effects of GLP-1 in ocular dynamics and the preclinical literature regarding GLP-1RA use in the management of several neuro-ophthalmic conditions, including diabetic retinopathy (DR), glaucoma, and idiopathic intracranial hypertension (IIH) are discussed.

Association of post-intervention pressure gradient with symptom-free at 6 months in idiopathic intracranial hypertension with venous sinus stenosis treated by stenting

OBJECTIVE

This study aimed to identify the key factors that might affect the clinical outcome of patients with idiopathic intracranial hypertension (IIH) and Venous sinus stenting (VSS).

METHODS

We performed an analysis of a prospectively collected database of patients with IIH and VSS who underwent stenting. The trans-stenotic pressure gradient was measured before and after intervention. In additional, patients' baseline characteristics, procedure details and clinical outcomes at 6-month follow-up (including changes in headache, visual impairment, papilledema, etc.) were recorded. The effects of post-intervention pressure gradient on symptom-free at 6 months were explored using logistic regression analysis, generalized additive model and receiver operator characteristic (ROC) curve.

RESULTS

Of 101 patients included in this study, the median pressure gradient across stenosis decreased from 19 mmHg before intervention to 2 mmHg after intervention. At 6 months, symptom-free was observed in 58 cases (57.4%). Multivariable logistic analysis and generalized additive model showed that post-intervention pressure gradient (increased by 1 mmHg) was independently and linearly correlated with symptom-free (OR = 0.79, 95% CI = 0.67-0.94). Moreover, the post-intervention pressure gradient revealed moderate discrimination with an area under ROC curve of 0.68 (95% CI = 0.57-0.78). Similar associations were observed for the disappearance of headache and papilledema, but not for the visual recovery.

CONCLUSION

The post-intervention pressure gradient may be a valid and reliable predictor of 6-month clinical outcome in patients with IIH and VSS treated by stenting. Nevertheless, external validation with blinded outcome is still needed to confirm its performance before clinical application.

Current and emerging diagnostic and management approaches for idiopathic intracranial hypertension

INTRODUCTION

Idiopathic intracranial hypertension is characterized by raised intracranial pressure that triggers disabling headaches and can cause permanent visual loss. There is an increased incidence and prevalence of the condition linked to location-specific obesity rates. There are no licensed treatments for the condition. The majority of approaches to managing the disease prioritize resolution of papilledema. However, evidence is emerging that idiopathic intracranial hypertension is a systemic metabolic disease.

AREAS COVERED

The aim of this review is to present the emerging pathophysiology evidence which is leading to novel targeted therapeutics. The diagnostic pathway is outlined. The current and potential management approaches for idiopathic intracranial hypertension are also discussed.

EXPERT OPINION

Idiopathic intracranial hypertension is a condition with metabolic dysregulation with systemic manifestations that are present over and above what can be expl.ained by obesity alone. While most of the current management of this condition focuses on the eyes, future management needs to address the disabling headaches and the systemic risks of preeclampsia, gestational diabetes, and major cardiovascular events.

"Idiopathic" intracranial hypertension: An update from neurointerventional research for clinicians

BACKGROUND

The recognition of venous sinus stenosis as a contributing factor in the majority of patients with idiopathic intracranial hypertension coupled with increasing cerebral venography and venous sinus stenting experience have dramatically improved our understanding of the pathophysiologic mechanisms driving this disease. There is now a dense, growing body of research in the neurointerventional literature detailing anatomical and physiological mechanisms of disease which has not been widely disseminated among clinicians.

METHODS

A literature search was conducted, covering the most recent neurointerventional literature on idiopathic intracranial hypertension, the pathophysiology of idiopathic intracranial hypertension, and management strategies (including venous sinus stenting), and subsequently summarized to provide a comprehensive review of the most recently published studies on idiopathic intracranial hypertension pathophysiology and management.

CONCLUSION

Recent studies in the neurointerventional literature have greatly improved our understanding of the pathophysiologic mechanisms causing idiopathic intracranial hypertension and its associated conditions. The ability to make individualized, patient-specific treatment approaches has been made possible by advances in our understanding of how venous sinus stenosis and cerebral venous hypertension fundamentally contribute to idiopathic intracranial hypertension.

Estimation of venous sinus pressure drop in patients with idiopathic intracranial hypertension using 4D-flow MRI

OBJECTIVE

We aimed to explore a non-invasive estimate of pressure drop in patients who undergo venous sinus stenting to treat idiopathic intracranial hypertension (IIH).

METHODS

This prospective study included 28 IIH patients scheduled for venous stenting. 4D-flow MRI was acquired 24-48 h before venous manometry. Manometry-obtained pressure drop (Mp) was dichotomized into low (Lp: 0-8 mmHg) and high (Hp: 8-30 mmHg) groups. Hemodynamic indices were compared between Lp and Hp. Trans-stenotic pressure drop was estimated by work-energy equation, simplified Bernoulli equation, vorticity magnitude, and velocity difference between inlet and outlet and was compared with Mp. Measurement agreement, correlation, and accuracy were evaluated using the κ coefficient, Pearson's r, and confusion matrix-derived accuracy.

RESULTS

Among 28 patients (mean age 38.8 ± 12.7), 19 (67.9%) were female. Work-energy equation-estimated pressure drop (WEp) had strong correlation (r = 0.91, 95% confidence interval [CI]: 0.81-0.96, p < 0.001) and high agreement (intraclass correlation coefficient = 0.90, 95% CI: 0.78-0.95, p < 0.001) with Mp. WEp classified Lp and Hp with an accuracy of 0.96. The κ value between WEp and Mp was 0.92 (95% CI: 0.78-1.00). In the work-energy equation, the viscosity energy term (V_e) had the largest weights, and the ratio of V_e to the summation of the three energy terms was 0.93 ± 0.07. V_e had strong correlation with mVort (r = 0.93, 95% CI: 0.85-0.97, p < 0.001), and mean vorticity magnitude was significantly elevated in Hp compared to that in Lp (259.8 vs. 174.9 mL/s, p < 0.001).

CONCLUSION

Trans-stenotic pressure drop in IIH can be estimated using the work-energy equation with favorable accuracy.

KEY POINTS

• Trans-stenotic pressure drop in patients with idiopathic intracranial hypertension can be estimated accurately with the work-energy equation using the 4D-flow MRI full velocity field. • Compared with traditional venous sinus manometry, the 4D-flow MRI-derived pressure drop is totally non-invasive and cost-saving. • 4D-flow MRI may help neurointerventionalist to select IIH patients suitable for venous sinus stenting.

Editorial Comment: Estimation of venous sinus pressure drop in patients with idiopathic intracranial hypertension using 4D-flow MRI

KEY POINTS

• Work-energy equation using 4D-flow MRI is a promising technique for non-invasive estimation of trans-stenotic pressure drop in patients with idiopathic intracranial hypertension.• Additional research with larger and multicentric prospective cohorts is needed to validate the results, along with improvement of the segmentation process with automated techniques and shortening of scanning times to allow for practical clinical use.

Neuroimaging in the diagnosis and treatment of intracranial pressure disorders

OBJECTIVE

To review the clinical features, proposed pathophysiology, and the role of medical imaging in the diagnosis and treatment of idiopathic intracranial hypertension and spontaneous intracranial hypotension.

METHODS

The authors conducted a narrative review of the current literature on intracranial hypertension and hypotension syndromes, with a focus on imaging findings and role of neurointerventional radiology as a therapeutic option for these pathologies.

RESULTS

Idiopathic intracranial hypertension commonly presents in obese women of childbearing age, being headache and papilledema the main clinical manifestations. Characteristic radiological findings consist of increased cerebrospinal fluid around the optic nerve, partially empty sella turcica and stenosis of the transverse sinuses. Transverse sinus stenting is a treatment alternative that has proven valuable utility in the recent years. Spontaneous intracranial hypotension in most of cases presents with orthostatic headache and has predilection for female population. The typical radiological features in the brain consist of subdural fluid collections, enhancement of the dura, engorgement of the venous structures, pituitary enlargement, and sagging of the brain. In this pathology, a cerebrospinal fluid leak in the spine associated with a defect in the dura, meningeal diverticulum, or a cerebrospinal fluid-venous leak must be actively ruled out.

CONCLUSIONS

Neurologic complaints secondary to changes in intracranial pressure exhibit certain clinical features that in combination with fairly specific radiological patterns allow a highly accurate diagnosis. The diverse specialists in neurosciences should be aware of the multiple image modalities in the study of these syndromes as well as the treatment alternatives by neurointerventional radiology.

Venous Sinus Stenting: Safety and Health Care Resource Evaluation for Optimal Recovery in an Evolving Health Care Environment

BACKGROUND

Increasing evidence supports the effectiveness of venous sinus stenting (VSS) with favorable outcomes, safety, and expenses compared with shunting for idiopathic intracranial hypertension. Yet, no evidence is available regarding optimal postoperative recovery, which has increasing importance with the burdens on health care imposed by the coronavirus disease 2019 pandemic. We examined adverse events and costs after VSS and propose an optimal recovery pathway to maximize patient safety and reduce stress on health care resources.

METHODS

A retrospective review was undertaken of elective VSS operations performed from May 2008 to August 2021 at a single institution. Primary data included hospital length of stay, intensive care unit (ICU) length of stay, adverse events, need for ICU interventions, and hospital costs.

RESULTS

Fifty-three patients (98.1% female) met the inclusion criteria. Of these patients, 51 (96.2%) were discharged on postoperative day (POD) 1 and 2 patients were discharged on POD 2. Both patients discharged on POD 2 remained because of groin hematomas from femoral artery access. There were no major complications or care that required an ICU. Eight patients (15.1%) were lateralized to other ICUs or remained in a postanesthesia care unit because the neurosciences ICU was above capacity. Total estimated cost for initial recovery day in a neurosciences ICU room was $2361 versus $882 for a neurosurgery/neurology ward room. In our cohort, ward convalescence would save an estimated $79,866 for bed placement alone and increase ICU bed availability.

CONCLUSIONS

Our findings reaffirm the safety of VSS. These patients should recover on a neurosurgery/neurology ward, which would save health care costs and increase ICU bed availability.

Arachnoid Granulation Causing Unilateral Pulsatile Tinnitus Treated With Dural Venous Sinus Stenting

BACKGROUND

Large arachnoid granulations that protrude into dural venous sinuses and partially obstruct outflow are an underappreciated etiology of pulsatile tinnitus (PT). Endovascular dural venous sinus stenting is thought to diminish turbulent venous outflow and may relieve obstruction caused by arachnoid granulations.

METHODS

Four patients at two institutions were evaluated for unilateral PT. Magnetic resonance imaging and digital subtraction angiography revealed moderate-to-severe stenoses from large arachnoid granulations within the implicated transverse sinus. All patients underwent venous manometry and endovascular sinus stenting.

RESULTS

All patients experienced immediate and complete remission of their PT. Stenoses were relieved by a mean of 93% by Warfarin-Aspirin Symptomatic Intracranial Disease criteria. There were no procedural or periprocedural complications. All patients continued to report complete symptom resolution at a mean of 8-month follow-up.

CONCLUSIONS

PT from arachnoid granulations are an underappreciated pathomechanism. Endovascular dural venous sinus stenting is an effective intervention for treating unilateral PT secondary to large arachnoid granulation.

Literature Commentary

In this issue of Journal of Neuro-Ophthalmology, Drs. Marc J. Dinkin, Deborah I. Friedman, and Mark L. Moster discuss the following 6 articles: Mollan SP, Mitchell JL, Yiangou A, Ottridge RS, Alimajstorovic Z, Cartwright DM, Hickman SJ, Markey KA, Singhal R, Tahrani AA, Frew E, Brock K, Sinclair AJ. Association of amount of weight lost after bariatric surgery with intracranial pressure in women with idiopathic intracranial hypertension. Neurology. 2022;99. doi:10.1212/WNL.0000000000200839.Nia AM, Srinivasan VM, Lall R, Kan P. Dural venous sinus stenting in idiopathic intracranial hypertension: a national database study of 541 patients. World Neurosurg. 2022:S1878-8750(22)01135-4. doi: 10.1016/j.wneu.2022.08.035.Eide PK, Hansson HA. A new perspective on the pathophysiology of idiopathic intracranial hypertension: role of the glia-neuro-vascular interface. Front Mol Neurosci. 2022;15:900057.Shah S, Morris P, Buciuc M, Tajfirouz D, Wingerchuk DM, Weinshenker BG, Eggenberger ER, Di Nome M, Pittock SJ, Flanagan EP, Bhatti MT, Chen JJ. Frequency of asymptomatic optic nerve enhancement in a large retrospective cohort of patients with aquaporin-4+ NMOSD. Neurology. 2022;99:e851-e857.Bsteh G, Krajnc N, Riedl K, Altmann P, Kornek B, Leutmezer F, Macher S, Mitsch C, Pruckner P, Rommer PS, Zulehner G, Pemp B, Berger T; Vienna Multiple Sclerosis Database Study Group. Retinal layer thinning after optic neuritis is associated with future relapse remission in relapsing multiple sclerosis. Neurology. 2022. doi: 10.1212/WNL.0000000000200970.Tsai RK, Lin KL, Huang CT, Wen YT. Transcriptomic analysis reveals that granulocyte colony-stimulating factor trigger a novel signaling pathway (TAF9-P53-TRIAP1-CASP3) to protect retinal ganglion cells after ischemic optic neuropathy. Int J Mol Sci. 2022;23:8359. doi: 10.3390/ijms23158359.