The anatomical basis of venographic filling defects of the transverse sinus

Angulation of the dural venous sinuses of the posterior cranial fossa: Anatomical study with clinical and surgical applications

Cerebral vein and dural venous sinus thromboses (CVST) account for 0.5%-1% of all strokes. Some structural factors associated with a potentially higher risk for developing CVST have been described. However, angulation of the dural venous sinuses (DVS) has yet to be studied as a structural factor. The current study was performed because this variable could be related to alterations in venous flow, thus predisposing to a greater risk of CVST development. Additionally, such information could help shed light on venous sinus stenosis (VSS) at or near the transverse-sigmoid junction. The angulations formed in the different segments of the grooves of the transverse (TS), sigmoid (SS), and superior sagittal sinuses (SSS) were measured in 52 skulls (104 sides). The overall angulation of the TS groove was measured using two reference points. Other variables were examined, such as the communication pattern at the sinuses' confluence and the sinus grooves' lengths and widths. The patterns of communication between sides were compared statistically. The most typical communication pattern at the sinuses' confluence was a right-dominant TS groove (82.98%). The mean angulations of the entire left TS groove at two different points (A and B) were 46° and 43°. Those of the right TS groove were 44° and 45°. The median angulations of the left and right SSS-transverse sinus junction grooves were 127° and 124°. The mean angulations of the left and right TS-SSJsv grooves were 111° (range 82°-152°) and 103° (range 79°-130°). Differentiating normal and abnormal angulations of the DVSs of the posterior cranial fossa can help to explain why some patients are more susceptible to pathologies affecting the DVSs, such as CVST and VSS. Future application of these findings to patients with such pathologies is now necessary to extrapolate our results.

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.

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.

Characteristics and Outcomes of the Idiopathic Intracranial Hypertension Treatment in Intrinsic and Extrinsic Stenosis: A Single-Center Experience in China

INTRODUCTION

This study aimed to explore the precipitating factors and evaluate the impact of different stenosis types on treatment outcomes in patients with idiopathic intracranial hypertension (IIH) and venous sinus stenosis (VSS).

METHODS

We recruited patients with IIH who presented with VSS, either intrinsic or extrinsic. We observed the clinical and laboratory findings, and we then compared the outcomes of stenting and medical treatment in different stenosis types.

RESULTS

Among 145 patients with IIH and VSS, 59 were of the intrinsic type and 86 were of the extrinsic type. Patients in the intrinsic group were older (42 vs. 34 years old, P < 0.001) and presented with higher pre-op gradient pressure (15 mmHg vs. 12 mmHg, P < 0.001). There was no significant difference between groups regarding other precipitating factors (P > 0.05). Stenting was significantly associated with complete resolution of the headache and impaired vision both in intrinsic (adjusted OR 0.017, 95% CI 0.001-0.35, P = 0.011; adjusted OR 0.056, 95% CI 0.004-0.697, P = 0.025, respectively) and extrinsic types of stenosis (adjusted OR 0.072, 95% CI 0.015-0.343, P = 0.001; adjusted OR 0.241, 95% CI 0.062-0.931, P = 0.039, respectively). Meanwhile, stenting was significantly associated with improvement of the papilledema in extrinsic-type stenosis compared with medical treatment (adjusted OR 0.017, 95% CI 0.002-0.135, P < 0.001).

CONCLUSION

Stenting may provide substantial clinical improvement in patients with IIH regardless of intrinsic or extrinsic stenosis type in our patient population, as noted in other series.

TRIAL REGISTRATION

Clinical trial registration number ChiCTR-ONN-17010421.

Intraluminal anatomy of the transverse sinus: implications for endovascular therapy

Trabeculae or septations in the transverse sinus can have potentially life-threatening clinical significance. The current study demonstrates trabecula/septum patterning within the transverse sinus with measurements and distribution data supplemented by imaging, and describes the possible etiology of idiopathic intracranial hypertension and turbulent blood flow in the transverse sinus. Twenty-four sides from 12 cadaveric heads, all fresh-frozen, were used (five males, seven females; age at death 65–91 years, mean 79.1 years). The length and diameter of the transverse sinus were measured along with the number and locations of septations/trabeculae and their tensile strength. The mean length of the transverse sinus was 68.43 mm on the right side and 74.31 mm on the left. A total of 42 septations were found in the 24 transverse sinuses. The number of septations per side ranged from zero to four with a mean of 1.75. The septations were located in the proximal 1/3 in 54.8% (23/42), the middle 1/3 in 21.4% (9/42), and the distal 1/3 in 23.8% (10/42). The work presented here furthers our understanding of transverse sinus anatomy, including its detailed internal architecture. The measurements can provide a technical guide for neurosurgeons and influence instrument selection when a large thrombus forms or anchors in one of these trabeculae or septa and necessitates treatment.

Update on Idiopathic Intracranial Hypertension

PURPOSE OF REVIEW

This review presents a critical appraisal of current therapeutic strategies for patients with idiopathic intracranial hypertension (IIH). We present the reader with the most recent evidence to support medical and surgical interventions in patients with IIH and provide recommendations about treatment initiation and escalation. We also indicate areas where knowledge gaps exist regarding therapeutic efficacy and superiority of one intervention over another.

RECENT FINDINGS

A double-masked, randomized prospective study of medical management of patients with mild IIH (Idiopathic Intracranial Hypertension Treatment Trial-IIHTT) has established that acetazolamide therapy has additional efficacy when compared to weight loss alone. Furthermore, management of IIH-related headache, even in patients with papilledema, may require treatment other than ICP lowering for patients to experience symptomatic relief. Finally, a number of uncontrolled interventional studies have shown transverse sinus stenting to be a potentially effective treatment for medically refractory IIH. Medical therapy with acetazolamide should be considered in addition to structured weight loss in patients with mild IIH. Surgical treatment for patients with vision-threatening disease IIH can be performed by either optic nerve sheath fenestration or cerebrospinal fluid diversion, with venous sinus stenting emerging as an alternate therapy. Headache relief from ICP lowering therapy is variable and often not sustained.

Cerebral venous sinuses thrombosis in both transverse sinus and torcula: Multistep endovascular treatment and stenting

Purpose Cerebral venous sinus thrombosis (CVST) is an unusual and potentially life-threatening condition with variable and nonspecific clinical symptoms and high morbimortality rates. Standard therapy consists of systemic anticoagulation; although there is no clear evidence about the best choice for treatment, intravenous heparin is used as the first-line treatment modality. Intravenous sinus thrombolysis can be an effective and relatively safe treatment for acutely deteriorating patients who have not responded to conventional therapy. This case report presents the possibility of endovascular treatment in multiple steps with mechanical thrombolysis with balloon, local pharmacological thrombolysis and stenting, in a patient with a severe form of CVST. Case summary A 67-year-old woman presented severe headache, agitation and confusion with diagnosis of venous sinus dural thrombosis in both lateral sinus and torcula. After 24 h there was neurological worsening evolving with seizures and numbness even after starting heparin, without sinus recanalization; CT scan showed left temporal intracerebral hemorrhage. We decided to take an endovascular approach in multiple steps. The first step was mechanical static thrombolysis with balloon; the second step was dynamic mechanical thrombolysis with a balloon partially deflated and "pulled"; the third step was local thrombolysis with Actilyse™; finally, the fourth step was angioplasty and reconstruction of the sinuses using multiple carotid stents and complete angiographic recanalization of both sinuses and torcula. After 24 h of endovascular treatment there was full clinical recovery and no tomographic complications. Conclusion This result shows that mechanical clot disruption, intrasinus thrombolysis and reconstruction of wall sinuses with stenting can be an endovascular option in the severe form of CVST with intracerebral hemorrhage and rapid worsening of neurological symptoms. Although this type of treatment can re-channel the occluded sinuses, further comparative and randomized studies are needed to clarify its efficacy versus other therapeutic modalities.

Imaging and interventions in idiopathic intracranial hypertension: A pictorial essay

Intracranial hypertension is a syndrome of elevated intracranial pressure that can be primary or secondary. The primary form, now termed idiopathic intracranial hypertension (IIH), was in the past a disease of exclusion and imaging played a limited role of excluding organic causes of raised intracranial pressure. However imaging markers have been described with patients with IIH at the orbit, sella and cerebral venous system. We wish to reiterate the characteristic imaging features of this poorly understood disease and also emphasise that stenting of the transverse sinus in select cases of IIH is an efficacious option.

[Intracranial hypertension and jugular vein thrombosis]

BACKGROUND

Pseudotumor cerebri is an idiopathic increase in intracranial pressure, which commonly affects obese women of fertile age. The diagnostic criteria according to the guidelines of the German Society for Neurology are increased cerebrospinal fluid (CSF) pressure, symptoms of increased CSF pressure, normal results of CSF examination, no relevant medication and a lack of structural and vascular lesions in magnetic resonance imaging (MRI).

CASE REPORT

This article presents the case of a 39-year-old male patient who presented at hospital with visual obscuration and recently occurred double vision. Except for a recently diagnosed thrombosis of the left jugular vein of unknown origin, there was nothing else of note in the medical history. Biomicroscopic examination showed papilledema with hemorrhages and cotton wool spots. The CSF opening pressure was initially > 50 cmH2O. During therapy by lumbar puncture (three times), oral carbonic anhydrase inhibitors and loop diuretics, the abducens nerve palsy and papilledema receded. Anticoagulation therapy (initially with coumarin derivatives, then with low molecular weight heparins) was unsuccessful in eliminating the thrombosis of the jugular vein. Surgical intervention was not recommended by the vascular surgeons.

CONCLUSION

This case report demonstrates the unusual combination of (idiopathic) intracranial hypertension and thrombosis of the jugular vein, which occurred spontaneously and without any detectable coagulation disorders.

Cerebral venous sinus stenting for pseudotumor cerebri: A review

Pseudotumor cerebri is characterized by headaches, visual field changes, papilledema and an elevated cerebrospinal fluid opening pressure without evidence of an intracranial mass. In the setting of failed medical therapy, surgical options such as ventriculoperitoneal shunts and optic nerve sheath fenestrations are considered. Recently, venous sinus stenting has emerged as a new treatment option for patients with pseudotumor cerebri. We review the role of cerebral venous sinus stenting in the management of patients with medically refractory pseudotumor cerebri. Although long- term studies are needed in this field, the current reports indicate a favorable outcome for preventing vision loss and symptom control.

Update on the pathophysiology and management of idiopathic intracranial hypertension

Idiopathic intracranial hypertension is a disease of unknown aetiology, typically affecting young obese women, producing a syndrome of increased intracranial pressure without identifiable cause. Despite a large number of hypotheses and publications over the past decade, the aetiology is still unknown. Vitamin A metabolism, adipose tissue as an actively secreting endocrine tissue and cerebral venous abnormalities are areas of active study regarding the pathophysiology of idiopathic intracranial hypertension. There continues to be no evidence based consensus or formal guidelines regarding management and treatment of the disease. Treatment studies show that the diagnostic lumbar puncture is a valuable intervention beyond its diagnostic importance, and that weight management is critical. However, many questions remain regarding the efficacy of acetazolamide, CSF shunting procedures and cerebral transverse venous sinus stenting.

Update on idiopathic intracranial hypertension

PURPOSE

To provide an update on various features of idiopathic intracranial hypertension.

DESIGN

Perspective.

METHODS

Selected articles on the epidemiology, clinical and imaging features, natural history, pathophysiology, and treatment of idiopathic intracranial hypertension were reviewed and interpreted in the context of the authors' clinical and research experience.

RESULTS

Idiopathic intracranial hypertension primarily is a disease of obese women of childbearing age, but it can affect patients of any weight, sex, and age. Although a relatively rare disorder, idiopathic intracranial hypertension's associated costs in the United States entail hundreds of millions of dollars. Even after treatment, headaches frequently are persistent and may require the continued involvement of a neurologist. Quality-of-life reductions and depression are common among idiopathic intracranial hypertension patients. However, visual dysfunction, especially visual field abnormalities, represents the major morbidity of this disorder, and serial automated perimetry remains the primary method of patient monitoring. Patients who are men, black, very obese, or anemic are at higher risk of visual loss. Vitamin A metabolism, adipose tissue as an actively secreting endocrine tissue, and cerebral venous abnormalities are areas of active study regarding the pathophysiology of idiopathic intracranial hypertension. Treatment studies show that lumbar puncture is a valuable treatment (in addition to its crucial diagnostic role), and that weight management is critical. However, open questions remain regarding the efficacy of acetazolamide, cerebrospinal fluid diversion procedures, and cerebral venous stenting.

CONCLUSIONS

Many questions remain unanswered about idiopathic intracranial hypertension. Ongoing studies, especially an ongoing National Institutes of Health-funded clinical trial of acetazolamide, should provide more insight into this important, yet poorly understood, syndrome of isolated intracranial hypertension.

Transverse sinus stenting for idiopathic intracranial hypertension: a review of 52 patients and of model predictions

BACKGROUND AND PURPOSE

Transverse sinus stenosis is common in patients with IIH. While the role of transverse sinus stenosis in IIH pathogenesis remains controversial, modeling studies suggest that stent placement within a transverse sinus stenosis with a significant pressure gradient should decrease cerebral venous pressure, improve CSF resorption in the venous system, and thereby reduce intracranial (CSF) pressure, improving the symptoms of IIH and reducing papilledema. We aimed to determine if IIH could be reliably treated by stent placement in transverse sinus stenosis.

MATERIALS AND METHODS

We reviewed the clinical, venographic, and intracranial pressure data before and after stent placement in transverse sinus stenosis in 52 of our own patients with IIH unresponsive to maximum acceptable medical treatment, treated since 2001 and followed between 2 months and 9 years.

RESULTS

Before stent placement, the mean superior sagittal sinus pressure was 34 mm Hg (462 mm H(2)0) with a mean transverse sinus stenosis gradient of 20 mm Hg. The mean lumbar CSF pressure before stent placement was 322 mm H(2)O. In all 52 patients, stent placement immediately eliminated the TSS pressure gradient, rapidly improved IIH symptoms, and abolished papilledema. In 6 patients, symptom relapse (headache) was associated with increased venous pressure and recurrent stenosis adjacent to the previous stent. In these cases, placement of another stent again removed the transverse sinus stenosis pressure gradient and improved symptoms. Of the 52 patients, 49 have been cured of all IIH symptoms.

CONCLUSIONS

These findings indicate a role for transverse sinus stent placement in the management of selected patients with IIH.