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

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.

Arachnoid granulations in idiopathic intracranial hypertension: Do they have an influence?

OBJECTIVE

The aim of this study was to investigate whether the relative narrowing of the dural venous sinuses by arachnoid granulations (AGs) is more pronounced in patients with idiopathic intracranial hypertension (IIH) compared to healthy controls.

BACKGROUND

IIH is characterized by increased intracranial pressure, which is associated with symptoms such as headache and visual disturbances. The role of cerebral venous drainage obstruction in IIH is the subject of ongoing research.

MATERIALS AND METHODS

In this retrospective case-control study, 3D contrast-enhanced magnetic resonance images of a cohort of 43 patients with IIH were evaluated for (1) the number of AGs per venous sinus and (2) the diameters of the dural venous sinuses at the site of an AG and at standardized measurement points. In addition, the minimum width of the transverse/sigmoid sinus was measured. All data were compared to the same data from a cohort of 43 control participants.

RESULTS

Patients with IIH showed less relative sinus narrowing by AG compared to controls (median: 7%, interquartile range [IQR] 10% vs. 11%, IQR 9% in controls; p = 0.009). In patients with IIH, sinus diameter was larger at the site of an AG (70 ± 25 mm2) compared to its diameter at the standardized measurement point (48 ± 23 mm2; p = 0.010). In the superior sagittal sinus (SSS), patients with IIH had smaller AGs (median: 3 mm2, IQR 2 mm2 vs. 5 mm2, IQR 3 mm2 in controls; p = 0.023) while the respective sinus segment was larger (median: 69 mm2; IQR 21 mm2 vs. 52 mm2, IQR 26 mm2 in controls; p = 0.002). The right transverse sinus was narrower in patients with IIH (41 ± 21 mm vs. 57 ± 20 mm in controls; p < 0.001).

CONCLUSIONS

In contrast to our hypothesis, patients with IIH showed less pronounced relative sinus narrowing by AG compared to controls, especially within the SSS, where AGs were smaller and the corresponding sinus segment wider. Smaller AGs could result in lower cerebrospinal fluid resorption, favoring the development of IIH. Conversely, the smaller AGs could also be a consequence of IIH due to backpressure in the SSS because of the narrower transverse/sigmoid sinus, which widens the SSS and compresses the AG.

National trends in the endovascular and surgical treatment of idiopathic intracranial hypertension

BACKGROUND

The pattern of surgical treatments for Idiopathic Intracranial Hypertension (IIH) in the United States is not well-studied, specifically the trend of utilizing endovascular venous stenting (EVS) as an emerging technique.

METHODS

In this cross-sectional study, we aimed to explore the national trend of utilizing different procedures for the treatment of IIH including EVS, Optic Nerve Sheath Fenestration (ONSF), and CSF Shunting, with a focus on novel endovascular procedures. Moreover, we explored rates of 90-day readmission and length of hospital stay following different procedures, besides the effects of sociodemographic and clinical parameters on procedure choice.

RESULTS

36,437 IIH patients were identified from records between 2010 and 2018. Those in the EVS group were 29 years old on average, and 93.4 % were female. Large academic hospital setting was independently associated with higher EVS utilization, while other factors were not predictive of procedure choice. The proportion of EVS use in IIH hospitalizations increased significantly from 2010 to 2018 (P < 0.001), while there was a relative decline in the frequency of shunting procedures (P = 0.001), with ONSF utilization remaining stable (P = 0.39). The rate of 90-day readmission and length of hospital stay were considerably lower following EVS compared to other procedures (Ps < 0.001).

CONCLUSION

This study presents novel population-level data on national trends in the frequency and outcome of EVS for IIH therapy. EVS was associated with shorter length of hospital stays and fewer readmission rates. In addition, a continuous increase in venous stenting compared to other procedures suggests an increasing role for endovascular therapies in IIH.

Differentiation Between the Low and High Trans-Stenotic Pressure Gradient in Patients With Idiopathic Intracranial Hypertension Using 4D Flow MRI-Derived Hemodynamic Parameters

BACKGROUND

Trans-stenotic pressure gradient (TPG) measurement is essential for idiopathic intracranial hypertension (IIH) patients with transverse sinus (TS) stenosis. Four-D flow MRI may provide a noninvasive imaging method for differentiation of IIH patients with different TPG.

PURPOSE

To investigate the associations between 4D flow parameters and TPG, and to evaluate the diagnostic performance of 4D flow parameters in differentiating patients with high TPG (GroupHP) from low TPG (GroupLP).

STUDY TYPE

Prospective.

POPULATION

31 IIH patients with TS stenosis (age, 38 ± 12 years; 23 females) and 5 healthy volunteers (age, 25 ± 1 years; 2 females).

FIELD STRENGTH/SEQUENCE

3T, 3D phase contrast MR venography, and gradient recalled echo 4D flow sequences.

ASSESSMENT

Scan-rescan reproducibility of 4D flow parameters were performed. The correlation between TPG and flow parameters was analyzed. The netflow and velocity difference between inflow plane, outflow plane, and the stenosis plane were calculated and compared between GroupHP and GroupLP.

STATISTICAL TESTS

Pearson's correlation or Spearman's rank correlation coefficient, Independent samples t-test or Wilcoxon rank-sum test, Intra-class correlation coefficient (ICC), Bland-Altman analyses, Receiver operating characteristic curves. A P value <0.05 was considered significant.

RESULTS

Significant correlations were found between TPG and netflow parameters including Favg,out-s, Favg,in-s, Fmax,out-s, and Fmax,in-s (r = 0.525-0.565). Significant differences were found in Favg,out-s, Fmax,out-s, Favg,in-s, and Fmax,in-s between GroupHP and GroupLP. Using the cut-off value of 2.19 mL/sec, the Favg,out-s showed good estimate performance in distinguishing GroupHP from GroupLP (AUC = 0.856). The ICC (ranged 0.905-0.948) and Bland-Altman plots indicated good scan-rescan reproducibility.

DATA CONCLUSIONS

4D flow MRI derived flow parameters showed good correlations with TPG in IIH patients with TS stenosis. Netflow difference between outflow and stenosis location at TS shows the good performance in differentiating GroupHP and GroupLP cases.

LEVEL OF EVIDENCE

2 TECHNICAL EFFICACY: Stage 2.

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.

Long-term efficacy of venous sinus stenting in the treatment of idiopathic intracranial hypertension

BACKGROUNDS

Previous studies have suggested that cerebral dural sinus stenosis could be a possible underlying cause of idiopathic intracranial hypertension (IIH). Venous sinus stenting (VSS) has emerged as a potential alternative for treating IIH related to dural sinus stenosis. However, most of the documented studies have been conducted in Western countries. In this study, we present the results of 16 Chinese IIH patients who underwent VSS treatment in our single center.

METHODS

We prospectively collected angiographic and manometric data from IIH patients who underwent angioplasty/stenting. All patients had confirmed dural sinus stenosis and had failed maximal medical therapy (MMT). Demographic, clinical, and radiological presentation, as well as long-term follow-up outcomes were collected retrospectively.

RESULTS

A total of 16 patients who underwent VSS were enrolled in the present study. Demographic data revealed a mean age of 40 (range 20-55), with 69% (11/16) being female, and a mean body mass index (BMI) of 27.05 (range 19.18-38.04) kg/m2 . All patients presented with papilledema and visual disturbances. During a median follow-up period of 47.5 months, 93.75% (15/16) of patients reported improvement in symptoms, although only 37.5% (6/16) experienced complete resolution. Headaches, blurred vision, and amaurosis related to increased pressure improved in 100% (8/8), 81.25% (13/16), and 75% (3/4) of patients, respectively. However, one patient suffered cerebral infarction and secondary epilepsy soon after VSS, and another patient had recurrence of symptoms due to stent wall thrombosis 2 years later.

CONCLUSIONS

The significance of venous sinus stenosis in the development of IIH may be undervalued. Our study, based on a Chinese case series, affirms the long-term safety and effectiveness of VSS in treating IIH patients with relatively lower BMI than those from Western countries.

Idiopathic intracranial hypertension in Omani adults: A tertiary center experience

BACKGROUND

To evaluate the clinical profile, risk factors, and ophthalmic diagnostic and monitoring tools in Omani patients with idiopathic intracranial hypertension (IIH) using optical coherence tomography (OCT).

METHODS

A retrospective single institutional cohort study on Omani patients with a fulfilled diagnosis of IIH from January 1, 2014, to January 1, 2020, was conducted. The data obtained from the neuro-ophthalmic clinic contained age of onset of the disease, gender of patients, body mass index (BMI), presence of other associated conditions, and medication use.

RESULTS

Our study group comprised 21 patients with IIH with an annual incidence rate of 2.8 per 100,000 population. Female-to-male ratio was 9.5:1 with a mean age of 27.24 ± 7.1. Headaches appeared to be the most prevalent symptom in 21 (100%) patients, followed by transient obscuration of vision in 9 (42.9%) patients and diplopia in 3 (14.3%) patients, and the least common symptom was pulsatile tinnitus in 2 (9.5%) patients. Increased BMI was seen in 19 (90.5%) patients and noted to be the most prevalent predisposing factor among our study group. The use of oral contraceptive pills was documented in 4 (19%) patients and 1 (4.8%) patient was noted to have polycystic ovary syndrome. All patients (100%) had a best-corrected visual acuity of 1.0 in both eyes pre- and postrecovery and 7 (33.3%) patients had an enlarged blind spot on visual field testing. All patients had papilledema on presentation and an average of 14.1 months to resolve to normal clinically and on OCT monitoring. All patients were treated with medications and only 1 (4.8%) continued to have intractable headaches that did not respond to maximum medical therapy and required surgery.

CONCLUSION

The incidence of IIH in the Omani population was found to be less than neighboring countries but comparable worldwide. OCT is considered a useful tool to confirm and document papilledema and more importantly monitor recovery.

A Case of Bilateral Papilledema With Improved Clinical Symptoms by Venous Stenting for Superior Sagittal Sinus Stenosis

Superior sagittal sinus (SSS) obstruction causes intracranial hypertension, often requiring surgical stenting. Consensus on treating brain venous sinus stenosis, another cause, is lacking. This study reports a case of SSS stenosis and intracranial hypertension treated with venous stenting, improving bilateral papilledema. A 51-year-old with a headache and visual disturbance had papilledema and visual field loss. MR venography showed SSS stenosis, leading to a neurosurgery referral. Lumbar puncture confirmed intracranial hypertension (>35 cmH2O), prompting venous stenting. Post-procedure, papilledema, headache, and visual field loss improved. Venous stenting could be effective for SSS stenosis with clinically proven or recurrent pressure differences. Further cases are needed for standardization.

Endoscopic endonasal optic nerve sheath decompression (EONSD) for idiopathic intracranial hypertension: Technical details and meta-analysis

BACKGROUND

The neurosurgical management of idiopathic intracranial hypertension (IIH) remains controversial. Although shunting and newer endovascular stenting techniques are part of the neurosurgical armamentarium to treat medically refractory IIH symptoms, optic nerve sheath fenestration has traditionally been performed by ophthalmologists.

OBJECTIVE

We present a detailed cadaveric dissection that simulates the endoscopic endonasal optic nerve sheath decompression (EONSD) technique along with the literature review.

METHODS

EONSD was performed in four freshly injected cadaveric specimens. Additionally, a systematic review from different electronic databases has been done.

RESULTS

Bilateral EONSD was performed in all specimens without significant technical difficulties. Based on our experience, there is no need to expose the periorbita or orbital apex. The primary anatomic landmarks were the optic canal, the lateral opticocarotid recess, the tuberculum, the limbus, and the clinoid segment of the internal carotid artery. Based on the systematic review, 68 patients (77.9% female) underwent EONSD, with a mean age of 33.4 ± 6.9 years in adult patients. Follow-up ranged from 3 to 58 months across different studies. The pooled meta-analysis showed headache, papilledema, and visual disturbance improvement in 78% [95%CI 0.65-0.90], 72% [95%CI 0.61-0.83], and 88% [95%CI 0.80-0.96] of cases who underwent EONSD, respectively. The subgroup analysis showed there was no statistically significant difference between unilateral and bilateral EONSD in terms of different measured outcomes.

CONCLUSION

EONSD is a feasible surgical procedure that may obviate the need for shunting in patients with IIH. Although clinical studies showed that EONSD is a safe and effective technique, further studies are required to establish the preferences of either unilateral or bilateral approaches.

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.

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.

Advances in the Understanding of the Complex Role of Venous Sinus Stenosis in Idiopathic Intracranial Hypertension

Idiopathic intracranial hypertension (IIH) is a disorder characterized by elevated intracranial pressure (ICP) that predominantly affects young obese women. IIH is a diagnosis of exclusion. That is, if increased ICP is suspected, magnetic resonance imaging and magnetic resonance venography of the brain are recommended to exclude secondary causes. Imaging findings, such as empty sella, orbital findings, meningocele, and encephalocele, are not diagnostic of ICP, nor does their absence exclude ICP either. Therefore, venous manometry is recommended as the gold standard for evaluation, regardless of previous anatomic imaging results. Venous manometry is an invasive examination that is frequently applied to derive physiologic information concerning the nature of the pressure gradient. However, the pathogenesis of IIH has not been fully elucidated. The presence of venous sinus stenosis in a subset of patients has provided some support for the potential mechanisms underlying this condition. Hence, this review provides an up‐to‐date discussion on the potential pathogenic mechanisms of IIH with a special focus on venous sinus stenosis.

Neuro-ophthalmological evaluation including optical coherence tomography surrounding venous sinus stenting in idiopathic intracranial hypertension with papilledema: a case series

Venous sinus stenting (VSS) for idiopathic intracranial hypertension (IIH) has been demonstrated to achieve significant symptom improvement while harboring a low periinterventional morbidity profile. Comprehensive neuro-ophthalmological monitoring represents a cornerstone of disease monitoring. The value of optical coherence tomography (OCT) requires further exploration. Patients with IIH and papilledema who underwent VSS between 04/2018 and 02/2021 were retrospectively reviewed. Clinical and radiological were analyzed. Neuro-ophthalmological data included visual acuity, visual fields, fundoscopy categorized via Frisén scale, and OCT obtained retinal nerve fiber layer (RNFL) thickness were analyzed. Of 39 IIH patients who underwent cerebral angiography with transverse-sigmoid sinus pressure evaluation, 18 patients with IIH and papilledema underwent 21 transverse-sigmoid sinus stenting (TSST) procedures. After TSST, manometry showed a significant reduction of maximum transverse sinus pressures and trans-stenotic gradient pressures (p = 0.005 and p < 0.001, respectively). Chronic headaches, visual disturbance resolved and pulsatile tinnitus improved significantly. Visual fields remained similar, while papilledema Frisén scales and visual acuity significantly improved. The OCT calculated RNFL thickness significantly decreased in all patients. Stratification according to a minimal-low degree (Frisén 1-2) and moderate-marked degree (Frisén 3-4) papilledema demonstrated a significant reduction of RNFL thickness in both groups. Venous sinus stenting provides favorable clinical and neuro-ophthalmological outcomes. This study demonstrates that neuro-ophthalmologic testing augmented with OCT evaluation provides objective data that can be used as a biomarker for treatment success for managing patients with different extents of papilledema and may inform patient management.

Posterior fossa volume in idiopathic intracranial hypertension: a magnetic resonance imaging-based study

BACKGROUND

The etiology of idiopathic intracranial hypertension (IIH) is uncertain. Studies suggest the fundamental cause of the Chiari 1 malformation, a congenitally hypoplastic posterior fossa, may explain the genesis of IIH in some patients.

PURPOSE

To assess the hypothesis that linear and volumetric measurements of the posterior fossa (PF) can be used as predictors of IIH.

MATERIAL AND METHODS

A retrospective analysis of magnetic resonance imaging (MRI) studies on 27 patients with IIH and 14 matched controls was performed. A volumetric sagittal magnetization prepared rapid acquisition gradient echo sequence was used to derive 10 linear cephalometric measurements. Total intracranial and bony posterior fossa volumes (PFVs) were derived by manual segmentation. The ratio of PFV to total intracranial volume was calculated.

RESULTS

In total, 41 participants were included, all women. Participants with IIH had higher median body mass index (BMI). No significant differences in linear cephalometric measurements, total intracranial volumes, and PFVs between the groups were identified. Linear measurements were not predictive of volumetric measurements. However, on multivariate logistic regression analysis, the likelihood of IIH decreased significantly per unit increase in relative PFV (odds ratio [OR]=3.66 × 10^-50; 95% confidence interval [CI]=1.39 × 10^-108 to 1.22 × 10^-5; P = 0.04). Conversely, the likelihood of IIH increased per unit BMI increase (OR=1.19; 95% CI=1.04-1.47; P = 0.02).

CONCLUSION

MRI-based volumetric measurements imply that PF alterations may be partly responsible for the development of IIH and Chiari 1 malformations. Symptoms of IIH may arise due to an interplay between these and metabolic, hormonal, or other factors.

Evaluation of the signs and symptoms of pseudotumor cerebri syndrome in pediatric population

PURPOSE

Pseudotumor cerebri syndrome (PTC) is characterized by increased intracranial pressure without a space-occupying lesion and a normal cerebrospinal fluid (CSF) composition without evidence of CSF infection. In this study, we aimed to compare the symptoms, signs, and clinical characteristics of patients presenting with a preliminary diagnosis of pseudotumor cerebri syndrome (PTC) who were diagnosed and not diagnosed with PTC.

METHOD

We conducted a retrospective study of patients who were referred to our clinic with signs and symptoms of PTC. We compared the patients' symptoms, signs, and clinical characteristics who were diagnosed with PTC with those who were not diagnosed with PTC using modified Dandy criteria.

RESULTS

Ninety-four patients with the pre-diagnosis of PTC were included in the study. LP procedure was done in all patients. After LP, 75.3% of the patients were diagnosed with PTC, but 24.7% did not meet the criteria for PTC. A statistically significant relationship was found between the increase in headache complaints when leaning forward, headache that keeps the child from playing, and the CSF pressure level (p = 0.014, p = 0.019; p < 0.05). There was no statistically significant correlation between papilledema and CSF pressure level (p > 0.05). A statistically significant relationship was found between papilledema grade and CSF pressure level (p = 0.038; p < 0.05), and the rate of high CSF pressure in the groups with Grades 2-3 and Grade 4 papilledema was higher than that in the group with Grade 1 papilledema. Cranial nerve 6 palsy (CN6) (p = 0.048) and flattening of the posterior aspect of the globe (FPS) are found independent risk factors (p = 0.004 p < 0.05).

CONCLUSIONS

PTC signs and symptoms show variability among pediatric population.

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.

Idiopathic intracranial hypertension: Do we diagnose and manage it appropriately in the light of current data?

BACKGROUND AND OBJECTIVE

Idiopathic intracranial hypertension (IIH) is an increase of intracranial pressure without a known cause, which usually presented with headache. This study aimed to evaluate the changing diagnosis and management approaches of neurologists for IIH in light of recent data.

METHODS

An online questionnaire about IIH was developed covering 28 questions, and five sections: demographic data, diagnosis, examination, treatment, and follow-up. We compared the approach of neurologists with 1-9 years of experience (group-A) with that of neurologists with more than 10 years' experience (group-B).

RESULTS

A total of 517 neurologists (group A: n = 252, group B: n = 265) participated in the study. Responder rate of questionarre is 18.3%. The approach to IIH in diagnosis, examination, treatment, and follow-up processes was similar in both groups. The younger group (group A) recognized all neuro-radiologic findings, especially flattening of the posterior aspect of the globe (p = 0.001) and tortuosity of the optic nerve (p < 0.001) at higher rates compared with group B. The most commonly used medical treatment was acetazolamide (99%); corticosteroids were used more frequently by group B (p < 0.001). Optic nerve sheath fenestration (88.3%) was the first-line and ventriculo-peritoneal shunt (70.5%) was the second preferred surgical approach. It was observed that serial lumbar puncture applications (57.0%) were preferred more frequently than venous sinus stenting (19.0%) and bariatric surgery (10.0%).

CONCLUSIONS

The changing information in the last decade about IIH was more closely followed by younger neurologists despite their lesser experience, but classic methods were preferred in surgical approaches in both groups. Our findings indicated that post-graduate education and guidelines should be disseminated for IIH.

Intracranial Access: Dural Venous Sinus Stenting: 2-Dimensional Operative Video

Cerebral venous sinus stenting has gained popularity in recent years as a safe and efficacious treatment of selected patients with idiopathic intracranial hypertension (IIH) and focal venous sinus stenosis.1-3 The main goal of treatment is to prevent visual loss, and often patients report resolution of headache and visual symptoms within 21 mo of mean follow-up.4-8 We present the case of a 57-yr-old woman with medically refractory IIH, bilateral sinus stenosis, and a mass lesion causing stenosis on the left. Venous angiogram with pressure monitoring was completed with the patient awake, which showed a significant pressure gradient on the right (19 mm Hg) and borderline gradient on the left (8 mm Hg). Options were reviewed and decision was made to proceed with the treatment of the right-sided stenosis with stenting and continue with the observation of the lesion on the left to prevent further visual deterioration. The patient consented for the procedure, and she tolerated the procedure well. Neurological exam remained at baseline, and she was discharged home on post-operative day #1. At 2 mo's follow-up, the patient reported improvement in headaches and remained intact neurologically.

A rare case of carotid body tumor associated with near complete cerebral sinus thrombosis and idiopathic intracranial hypertension. Management strategy and review of the literature

Background

Carotid body tumors (CBTs) are rare hypervascular lesions with critical location which makes them very challenging to treat. In rare occasions, compression of the jugular vein from the tumor mass could predispose to progressive thrombosis of intracranial venous sinuses. The latter consequently leads to intracranial hypertension (pseudotumor cerebri) with the accompanying danger to the vision. Herewith, we present our management strategy for this rare presentation of CBTs.

Case Description

A 38-year-old woman, with no medical history, was admitted in the emergency unit with acute onset of headache, dizziness, and vomiting. On the diagnostic imaging studies (CT venography and MRI) a near total occlusion of all cerebral venous sinuses and a large CBT (Shambin Type II) were diagnosed. Initially, the patient was treated with anticoagulants for the thrombosis and with lumbo-peritoneal (LP) shunt for the management of pseudotumor cerebri. At a second stage, after resolution of the cerebral sinus thrombosis, the CBT was completely resected under electrophysiological monitoring, without preoperative embolization. At 1-year follow-up, the patient is neurologically intact with functioning LP shunt, patent cerebral venous sinuses, without tumor recurrence.

Conclusion

We present a rare case of CBT with intracranial complications, which was managed successfully by staged treatment. Careful study of the preoperative radiological and laboratory data, thorough preoperative planning of the tridimensional lesion anatomy, as well as meticulous microsurgical technique under intraoperative electrophysiological monitoring was essential for the successful outcome of the case.

Major complications of dural venous sinus stenting for idiopathic intracranial hypertension: case series and management considerations

BACKGROUND

Venous sinus stenting (VSS) is a safe, effective, and increasingly popular treatment option for selected patients with idiopathic intracranial hypertension (IIH). Serious complications associated with VSS are rarely reported.

METHODS

Serious complications after VSS were identified retrospectively from multicenter databases. The cases are presented and management strategies are discussed.

RESULTS

Six major acute and chronic complications after VSS were selected from a total of 811 VSS procedures and 1466 venograms for IIH. These included an acute subdural hematoma from venous extravasation, cases of both intraprocedural and delayed stent thrombosis, an ultimately fatal cerebellar hemorrhage resulting in acute obstructive hydrocephalus, venous microcatheter perforation during venography and manometry, and a patient who developed subarachnoid hemorrhage and subdural hematoma after cerebellar cortical vein perforation. The six cases are reviewed and learning points regarding complication avoidance and management are presented.

CONCLUSION

We report on six rare, major complications after VSS for IIH. Familiarity with these potential complications and appropriate timely management may allow for good clinical outcomes.

Neurosurgical CSF Diversion in Idiopathic Intracranial Hypertension: A Narrative Review

The prevalence of idiopathic intracranial hypertension (IIH), a complex disorder, is increasing globally in association with obesity. The IIH syndrome occurs as the result of elevated intracranial pressure, which can cause permanent visual impairment and loss if not adequately managed. CSF diversion via ventriculoperitoneal and lumboperitoneal shunts is a well-established strategy to protect vision in medically refractory cases. Success of CSF diversion is compromised by high rates of complication; including over-drainage, obstruction, and infection. This review outlines currently used techniques and technologies in the management of IIH. Neurosurgical CSF diversion is a vital component of the multidisciplinary management of IIH.

Transverse sinus stenting for treatment of papilloedema secondary to a large brain herniation into a dural venous sinus with associated tectal plate lesion: Case report and literature review

Brain herniation into a dural venous sinus is a rare entity of unknown clinical significance without a clear relationship to raised intracranial pressure. There are yet to be detailed reports of interventional neuroradiology procedures involving sinus stenting across brain herniations. The authors of this paper present the first case of a stent placed across a large brain herniation into the transverse sinus in a patient with a tectal plate lesion and features of chronically raised intracranial pressure. This case demonstrates objective resolution of papilloedema and venous sinus pressure gradient at six months without complication.

Near-Infrared Spectroscopy (NIRS) in Traumatic Brain Injury (TBI)

Traumatic brain injury (TBI) occurs when a sudden trauma causes damage to the brain. TBI can result when the head suddenly and violently impacts an object or when an object pierces the skull and enters brain tissue. Secondary injuries after traumatic brain injury (TBI) can lead to impairments on cerebral oxygenation and autoregulation. Considering that secondary brain injuries often take place within the first hours after the trauma, noninvasive monitoring might be helpful in providing early information on the brain's condition. Near-infrared spectroscopy (NIRS) is an emerging noninvasive monitoring modality based on chromophore absorption of infrared light with the capability of monitoring perfusion of the brain. This review investigates the main applications of NIRS in TBI monitoring and presents a thorough revision of those applications on oxygenation and autoregulation monitoring. Databases such as PubMed, EMBASE, Web of Science, Scopus, and Cochrane library were utilized in identifying 72 publications spanning between 1977 and 2020 which were directly relevant to this review. The majority of the evidence found used NIRS for diagnosis applications, especially in oxygenation and autoregulation monitoring (59%). It was not surprising that nearly all the patients were male adults with severe trauma who were monitored mostly with continue wave NIRS or spatially resolved spectroscopy NIRS and an invasive monitoring device. In general, a high proportion of the assessed papers have concluded that NIRS could be a potential noninvasive technique for assessing TBI, despite the various methodological and technological limitations of NIRS.

Pathogenesis and Management in Cerebrovenous Outflow Disorders

In keeping with its status as one of the major causes of disability and mortality worldwide, brain damage induced by cerebral arterial disease has been the subject of several decades of scientific investigation, which has resulted in a vastly improved understanding of its pathogenesis. Brain injury mediated by venous etiologies, however, such as cerebral, jugular, and vertebral venous outflow disturbance, have been largely ignored by clinicians. Unfortunately, this inattention is not proportional to the severity of cerebral venous diseases, as the impact they exact on the quality of life of affected patients may be no less than that of arterial diseases. This is evident in disease sequelae such as cerebral venous thrombosis (CVT)-mediated visual impairment, epilepsy, and intracranial hypertension; and the long-term unbearable head noise, tinnitus, headache, dizziness, sleeping disorder, and even severe intracranial hypertension induced by non-thrombotic cerebral venous sinus (CVS) stenosis and/or internal jugular venous (IJV) stenosis. In addition, the vertebral venous system (VVS), a large volume, valveless vascular network that stretches from the brain to the pelvis, provides a conduit for diffuse transmission of tumors, infections, or emboli, with potentially devastating clinical consequences. Moreover, the lack of specific features and focal neurologic signs seen with arterial etiologies render cerebral venous disease prone to both to misdiagnoses and missed diagnoses. It is therefore imperative that awareness be raised, and that as comprehensive an understanding as possible of these issues be cultivated. In this review, we attempt to facilitate these goals by systematically summarizing recent advances in the diagnosis and treatment of these entities, including CVT, CVS stenosis, and IJV stenosis, with the aim of providing a valid, practical reference for clinicians.

Acute cerebral venous outflow obstruction during convexity meningioma resection

BACKGROUND

Cerebral venous outflow obstruction involves idiopathic intracranial hypertension, and the most common related condition is dural venous sinus stenosis or, in other words, an obstruction of the dural venous sinuses. In these cases, the pathological process is often chronic, displays only mild symptoms, and rarely requires urgent surgical intervention. In this study, we present a unique case involving an acute cerebral venous outflow obstruction that occurred during meningioma resection that ultimately had catastrophic consequences.

MATERIALS AND METHODS

The patient's preoperative imaging only revealed an unremarkable frontal convexity meningioma with an average diameter exceeding 8 cm. She was admitted for a scheduled right frontoparietal craniotomy for lesion resection.

RESULTS

The patient's unique congenital dural venous sinus structure along with a non-surgical epidural hematoma both contributed to a catastrophic outcome, causing a progressive hemispheric encephalocele, significant blood loss, and wound closure difficulties.

CONCLUSION

Neurosurgeons should place an additional focus on cerebral venous outflow patency during tumor resection, even if the tumor does not involve the transverse or sigmoid sinuses. It is well known that the tacking sutures play an essential role in preventing an epidural hematoma, but the procedure to mitigate hematomas occurring outside the surgical field of view is not fully recognized by neurosurgeons. If dural tacking sutures are placed after complete tumor resection, the prophylactic effect for preventing EDH in the non-surgical areas may not be guaranteed. Therefore, we strongly advocate for the tacking sutures to be accurately placed before dural incisions are made.

Psychiatric symptoms are frequent in idiopathic intracranial hypertension patients

Idiopathic intracranial hypertension (IIH) is a rare disease with an incidence rate of 0.5-2.0/100,000/year. Characteristic symptoms are headache and several degrees of visual impairment. Psychiatric symptoms in association with IIH are usually poorly described and underestimated. In this study, we evaluated IIH subjects to determine the association with psychiatric symptoms. We evaluated thirty consecutive patients with IIH submitted to neurosurgery from January 2017 to January 2020 in two Brazilian tertiary hospitals. They underwent clinical evaluation, obtaining medical history, comorbidities, body mass index (BMI-kg/m²), and applying Neuropsychiatric Inventory Questionnaire (NPI-Q). There were 28 females and 2 males. Ages ranged from 18 to 66 years old, with mean age of 37.97 ± 12.78. Twenty-five (83%) presented comorbidities, being obese and having arterial hypertension the most frequent. Body mass index ranged from 25 to 35 kg/m² and mean value was 31 ± 3.42. After application of Neuropsychiatric Interview, 26 of 30 presented psychiatric symptoms (86%). Depression-anxiety syndromes were reported in 25 patients (83%). Nighttime disturbances were reported by 14 subjects (46%). Appetite and eating disorders were described by 23 (76%). Psychiatric symptoms in association with IIH are usually poorly described and underestimated. In our sample, twenty-six out of 30 (86%) reported psychiatric symptoms. We highlight the high prevalence of psychiatric symptoms among IIH patients and the need of managing these patients with a multidisciplinary team, including psychiatrists.

Venous sinus stenting improves cerebral autoregulation in a patient with venous sinus stenosis: a case report

BACKGROUND

Venous sinus stenosis (VSS) is a type of cerebral venous vascular disease. Cerebral autoregulation is an indicator of cerebral arterial function. The cerebral circulatory system is composed of the venous system and arterial system. Impaired venous function may affect arterial function. Thus, cerebral venous stenosis may influence cerebral autoregulation.

CASE PRESENTATION

In this case, a 50-year-old woman with transient blindness and headache was admitted to the hospital. The patient was diagnosed with VSS. A stent was placed at the stenosis. The stent released the intravenous pressure and remitted the patient's symptoms. Measurements of dynamic cerebral autoregulation (dCA) were performed at 3 time points: before stenting, after stenting, and 3 months later. The dCA gradually improved after stenting.

CONCLUSION

VSS may have an influence on cerebral autoregulation, and effective treatment improves cerebral autoregulation in patients with VSS.

Familial Intracranial Hypertension in 2 Brothers With PTEN Mutation: Expansion of the Phenotypic Spectrum

PTEN (Phosphatase and Tensin Homolog on chromosome TEN) encodes a vastly expressed tumor suppressor protein that antagonizes the PI3 K signaling pathway and alters the MTOR pathway. Mutations in PTEN have been described in association with a number of syndromes including PTEN hamartoma-tumor syndrome, macrocephaly/autism, and juvenile polyposis of infancy. Although there is a wide variability in the clinical and radiologic presentations of PTEN-related phenotypes, the most consistent features include macrocephaly and increased tumorigenesis. Intracranial hypertension may be idiopathic or secondary to multiple etiologies. We describe 2 siblings harboring a PTEN mutation who presented with macrocephaly and intracranial hypertension. Repeat brain MRIs were normal in both. Acetazolamide treatment normalized intracranial pressure, but several trials of medication tapering led to recurrence of intracranial hypertension symptoms. The clinical presentation of our patients expands the PTEN-related phenotypes. We discuss the possible pathophysiology in view of PTEN function.