Chordae Willisii of the dural sinuses: an anatomical study using magnetic resonance imaging.

PURPOSE: The chordae Willisii (CWs), trabecular projections into the lumen of the dural sinuses, are not well understood. We aimed to explore them using magnetic resonance imaging (MRI). METHODS: Eighty-five patients underwent volumetric contrast-enhanced MRI, while another 30 underwent a fluid-attenuated inversion recovery (FLAIR) sequence in the coronal section. RESULTS: The CWs were detected as linear filling defects lying in the dural sinuses, adjacent to the surrounding dura mater. They were found in the superior sagittal sinus (SSS) in 68.2% of the patients, most frequently in the middle third, with laminar appearance. In 27.1% of the patients, the CWs divided the SSS lumen into separate channels. The CWs were identified in the transverse sinus, transverse-sigmoid sinus junctional area and sigmoid sinus, and straight sinus in 54.1, 47.1, and 8.2%, respectively. On the FLAIR images, dural septi partially dividing the SSS lumen were identified in all patients. In addition, in 73.3% of the patients, fine linear structures were observed in the lumen with inconstant arrangements. CONCLUSIONS: The CWs may be constant structures distributed over the lumen of the intracranial dural sinuses. Contrast-enhanced MRI may be useful for detecting laminar CWs. The FLAIR sequence may be advantageous for delineating the dural septi projecting into the lumen of the dural sinuses.

Sex-based difference in selected stroke etiologies: cerebral dural sinus venous thrombosis, reversible cerebral vasoconstriction syndrome, dissection, migraine, pregnancy/puerperium/OC use.

Females are at higher risk than males for a multitude of cerebrovascular conditions, both common and rare; partially resulting from a complex interplay between differing process involving genetics, hormonal influences, common cerebrovascular risk factors among others. Specific topics including cervical artery dissection, cerebral dural sinus venous thrombosis, reversible cerebral vasoconstriction syndrome, migraine, along with these disorders in the setting of pregnancy, puerperium and oral contraceptive utilization. Epidemiology, pathophysiology, presentation, basics of management and outcomes are presented, with sex differences throughout.

Venous Anatomy of the Central Nervous System.

Comprehensive understanding of venous anatomy is a key factor in the approach to a multitude of conditions. Moreover, the venous system has become the center of attention as a new frontier for treatment of diseases such as idiopathic intracranial hypertension (IIH), arteriovenous malformation (AVM), pulsatile tinnitus, hydrocephalus, and cerebrospinal fluid (CSF) venous fistulas. Its knowledge is ever more an essential requirement of the modern brain physician. In this article, the authors explore the descriptive and functional anatomy of the venous system of the CNS in 5 subsections: embryology, dural sinuses, cortical veins, deep veins, and spinal veins.

New recommendations on cerebral venous and dural sinus thrombosis from the German consensus-based (S2k) guideline.

Over the last years, new evidence has accumulated on multiple aspects of diagnosis and management of cerebral venous and dural sinus thrombosis (CVT) including identification of new risk factors, studies on interventional treatment as well as treatment with direct oral anticoagulants. Based on the GRADE questions of the European Stroke Organization guideline on this topic, the new German guideline on CVT is a consensus between expert representatives of Austria, Germany and Switzerland. New recommendations include:• CVT occurring in the first weeks after SARS-CoV-2 vaccination with vector vaccines may be associated with severe thrombocytopenia, indicating the presence of a prothrombotic immunogenic cause (Vaccine-induced immune thrombotic thrombocytopenia; VITT).• D-dimer testing to rule out CVT cannot be recommended and should therefore not be routinely performed.• Thrombophilia screening is not generally recommended in patients with CVT. It should be considered in young patients, in spontaneous CVT, in recurrent thrombosis and/or in case of a positive family history of venous thromboembolism, and if a change in therapy results from a positive finding.• Patients with CVT should preferably be treated with low molecular weight heparine (LMWH) instead of unfractionated heparine in the acute phase.• On an individual basis, endovascular recanalization in a neurointerventional center may be considered for patients who deteriorate under adequate anticoagulation.• Despite the overall low level of evidence, surgical decompression should be performed in patients with CVT, parenchymal lesions (congestive edema and/or hemorrhage) and impending incarceration to prevent death.• Following the acute phase, oral anticoagulation with direct oral anticoagulants instead of vitamin K antagonists should be given for 3 to 12 months to enhance recanalization and prevent recurrent CVT as well as extracerebral venous thrombosis.• Women with previous CVT in connection with the use of combined hormonal contraceptives or pregnancy shall refrain from continuing or restarting contraception with oestrogen-progestagen combinations due to an increased risk of recurrence if anticoagulation is no longer used.• Women with previous CVT and without contraindications should receive LMWH prophylaxis during pregnancy and for at least 6 weeks post partum.Although the level of evidence supporting these recommendations is mostly low, evidence from deep venous thrombosis as well as current clinical experience can justify the new recommendations.This article is an abridged translation of the German guideline, which is available online.

Dural sinus malformation presenting with proptosis: report and review of a rare entity.

Dural sinus malformation (DSM) is a rare vascular malformation characterized by the dilatation of a dural venous sinus with or without an anomalous jugular bulb. Its presentation with venous-reflux-related secondary proptosis is anecdotal, with only six such cases reported so far. We report a 17-month-old boy who presented with a progressive proptosis of the right eye secondary to a DSM of the transverse sinus and torcula. Following endovascular embolization of the arterio-venous fistula, complete thrombosis of the venous lake and improvement in proptosis was noted at 6-month follow-up. Prognosis of this rare malformation is variable and dependent on specific angio-architectural features.

3D digital subtracted angiography venous roadmapping for endovascular management of dural venous stenosis.

Stenting of the dural venous sinuses has emerged as a therapeutic option for intracranial hypertension and pulsatile tinnitus. However, venous endovascular navigation faces challenges due to lower-quality roadmaps compared to arterial navigation. This study explores the application of three-dimensional (3D) rotational venography in assessing the cerebral venous vasculature and its potential for venous navigation. The methods involve venous 3D digital subtracted angiography (DSA) in patients with dural venous stenosis, with image acquisition using a biplane angiographic system. The results highlight the enhanced spatial resolution of 3D venous imaging, providing anatomical information crucial for precise characterization of stenosis and understanding cortical venous drainage. 3D venous roadmapping is shown to improve endovascular venous navigation, offering synchronized and rotatable 3D roadmaps, providing a comprehensive approach to optimize endovascular venous interventions.

Eclipse balloon-assisted straight sinus thrombectomy: A novel technique.

Cerebral venous sinus thrombosis comprises 0.5% of all strokes and usually affects young adults. Straight sinus involvement is relatively rare, and it is associated with poor prognosis. Intravenous anticoagulation is considered the first line of treatment. Endovascular approaches such as direct catheter thrombolysis, balloon-assisted thrombolysis, and mechanical thrombectomy may be more efficient and should be considered in cases in which there is involvement of the deep venous system, declining neurological status, or less invasive treatment options have failed. In this work, we describe a novel technique of ECLIPSE 2L balloon (Balt, Irvine, CA) assisted mechanical thrombectomy for straight sinus thrombosis and a review of dural sinus thrombosis management.

A Prospective Cohort Study Characterizing Incidence of Dural Venous Sinus Thrombosis in Traumatic Brain Injury Patients with Skull Fractures.

BACKGROUND: Limited retrospective data suggest that dural venous sinus thrombosis (DVST) in traumatic brain injury (TBI) patients with skull fractures is common and associated with significant morbidity and mortality. Prospective data accurately characterizing the incidence of DVST in patients with high-risk TBI are sparse but are needed to develop evidence-based TBI management guidelines. METHODS: After obtaining institutional approval, 36 adult patients with TBI with skull fractures admitted to an Australian level III adult intensive care unit between April 2022 and January 2023 were prospectively recruited and underwent computed tomography venography or magnetic resonance venography within 72 hours of injury. When available, daily maximum intracranial pressure was recorded. RESULTS: Dural venous sinus abnormality was common (36.1%, 95% confidence interval 22.5%-52.4%) and strongly associated with DVST (P = 0.003). The incidence of DVST was 13.9% (95% confidence interval 6.1%-28.7%), which was lower than incidence reported in previous retrospective studies. Of DVSTs confirmed by computed tomography venography, 80% occurred in patients with extensive skull fractures including temporal or parietal bone fractures in conjunction with occipital bone fractures (P = 0.006). However, dural venous sinus abnormality and DVST were not associated with an increase in maximum daily intracranial pressure within the first 7 days after injury. CONCLUSIONS: Dural venous sinus abnormality was common in TBI patients with skull fractures requiring intensive care unit admission. DVST was confirmed in more than one third of these patients, especially patients with concomitant temporal or parietal and occipital bone fractures. Computed tomography venography is recommended for this subgroup of TBI patients.

Magnetic Resonance Imaging of Dural Sinus Malformation in a Fetus: A Case Report.

BACKGROUND: Dural sinus malformation (DSM) is a rather rare congenital condition that can be encountered in the fetus and infants. The cause and etiology of DSM remain unclear. Obstetric ultrasound plays a key role in screening fetal brain malformations, and MRI is frequently used as a complementary method to confirm the diagnosis and provide more details. OBJECTIVE: Here, we present a fetus with DSM by multiple imaging methods to help better understand the imaging characteristics of this malformation. CASE PRESENTATION: A 22-year-old primipara was referred to our hospital at 25 weeks of gestation following the detection of a fetal intracranial mass without any symptoms. A prenatal ultrasound performed in our hospital at 25 + 2 gestational weeks showed a large anechoic mass with liquid dark space, while no blood flow was detected. After the initial evaluation, this primipara received a prenatal MRI in our hospital. This examination at 25 + 5 gestational weeks delineated a fan-shaped mass in the torcular herophili, which was iso-to hyperintense on T1WI and hypointense on T2WI. At the lower part of this lesion, a quasi-circular hyperintense on T1WI and a signal slightly hyperintense on T2WI could be seen. Meanwhile, the adjacent brain parenchyma was compressed by the mass. CONCLUSION: We reviewed the current literature to obtain a better understanding of the mechanisms, imaging characteristics, and survival status of DSM. Although the primipara of the present study regretfully opted for elective termination of pregnancy, the reevaluation of DSM survival deserves more attention because of the better survival data from recent studies.

Multimodality imaging in cerebral venous thrombosis: a synopsis for emergency radiologist.

Cerebral venous thrombosis (CVT) is an uncommon but potentially fatal condition which presents with a wide range of symptoms. Some of these presenting features are vague thus contributing to the delay in diagnosis. A prompt diagnosis and initiation of appropriate therapy are therefore of paramount importance. In this pictorial, we have tried to illustrate the direct and indirect imaging features of CVT in detail on multiple imaging modalities, along with the potential pitfalls of imaging.

Use of greyscale and Doppler ultrasound in initial evaluation and follow-up of neurovascular malformations in children.

Pediatric intracranial arteriovenous shunts are rare vascular malformations that can be diagnosed prenatally or postnatally, as an incidental finding or due to complications. We propose a review of cerebral vascular malformations in newborns and infants with special emphasis on neurosonography and Doppler ultrasound as the first diagnostic method. Sonography can thus contribute in the planning of further studies that are always necessary, and in post-therapy follow-up.

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.

Transarterial embolization of sinus dural arteriovenous fistula using non-adhesive liquid embolic material.

Objective: The objective is to report our experience of transarterial embolization of sinus dural arteriovenous fistula (DAVF) using non-adhesive liquid embolic material.Materials and methods: In 3 cases of Borden type II sinus DAVFs, a Copernic balloon was used to protect sagittal sinus in one patient, palliative Onyx embolization was performed to protect transverse sinus in one patient and EVAL/DMSO/ethanol mixture (EVAL, SUCCESS, Shandong, China) was used in the last patient.Results: Two Borden type II DAVFs were changed into type I DAVF and one was cured. The dural sinus was patent after successful Onyx embolization in 3 cases resulting in well patient recovery. There were no treatment-related events.Conclusion: Transarterial embolization of sinus DAVF using non-adhesive liquid embolic material could be effective and safe with sinus protection techniques.

A Rare Case of Unprovoked Deep Cerebral Venous Sinus Thrombosis With Associated Petechial Hemorrhage.

A 73-year-old male with hyperlipidemia and prior squamous cell carcinoma presented with a new-onset generalized tonic-clonic seizure and left-sided weakness. He had a progressively worsening cervical and occipital headache for nine days and was initially evaluated with an unremarkable CT head. The patient arrived at the emergency department with a left gaze deviation, prompting a "Code Neuro." CT angiography (CTA) detected a large dural sinus thrombosis, which was confirmed with a CT venogram and brain MRI. The patient was closely monitored in the intensive care unit and managed with heparin, nicardipine, and hypertonic saline boluses. Neurosurgery opted against surgical intervention. EEG revealed right hemisphere focal dysfunction. Recanalization occurred on hospital day 6. The patient was transitioned to apixaban upon discharge and instructed to follow up with hematology for a hypercoagulable workup. This case highlights the diagnostic complexity of cerebral venous sinus thrombosis (CVST), urging consideration of a differential even in atypical patients. We hope reporting this case will prompt clinicians to consider CVST in patients with non-specific symptoms, leading to timely diagnosis and treatment.

In-out-in technique for petrosal sinus dural arteriovenous fistula obliteration: How I Do It.

BACKGROUND: Dural arteriovenous fistulas (dAVFs) at the superior petrosal sinus are a rare but important subtype that pose a high risk of mortality and morbidity. Treatment for these lesions can be challenging with stand-alone endovascular methods. METHODS: We describe our "in-out-in" technique for disconnecting dAVFs at the superior petrosal sinus, which includes definitive sacrifice of the superior petrosal sinus and the transverse sigmoid sinus, if involved. This method achieves complete fistula obliteration and minimizes recurrence risk with new arterial feeders. CONCLUSIONS: The in-out-in technique is a safe and effective approach for the treatment of dAVFs involving the superior petrosal sinus.

Widespread distribution of lymphatic vessels in human dura mater remote from sinus veins.

Background and purpose: Previous experimental studies have shown that meningeal lymphatic vessels are located primarily along the walls of the dural sinus veins. Whether they are more widespread throughout human dura mater has presently not been characterized. The present study explored in humans whether meningeal lymphatic vessels may be identified remote from the sinus veins and whether they differ in the various location of dura mater. Methods: We included 15 patients who underwent neurosurgery, in whom dura mater was removed as part of the planned procedure. Tissue was prepared for immunohistochemistry using the lymphatic endothelial cell markers lymphatic vessel endothelial hyaluronan receptor 1 protein (LYVE-1), podoplanin and vascular endothelial growth factor receptor 3 (VEGFR3). Results: Lymphatic endothelial cell positive cells were found in dura mater at the posterior fossa (n = 8), temporal skull base (n = 5), frontal convexity (n = 1), and cranio-cervical junction (n = 1). They were most commonly seen remote from blood vessels, but also occurred along blood vessels, and seemed to be most abundant at the skull base. Conclusion: The present observations show that human lymphatic vessels are widespread in dura mater, not solely lining the dural sinuses.

Cerebral Venous Thrombosis in Young Adults: Unknown Origins.

Cerebral venous thrombosis (CVT) is a relatively rare neurological disorder that may result in significant morbidity if not diagnosed and managed promptly. The clinical presentation of CVT is nonspecific and highly variable with acute, subacute, or chronic onset. It most often presents as a headache but may present with focal neurological symptoms, symptoms of intracranial hypertension, or encephalopathy. The predisposing factors for CVT are mainly acquired and genetic hypercoagulable conditions. However, the epidemiology, predisposing factors, and clinical presentation of CVT are not clearly established given the rare nature of the condition. We present a case series of three young patients who did not have any classic underlying etiology for CVT or any prior diagnosis of venous thrombosis. We want to report this case series to show that a high index of suspicion should be maintained regardless of the absence of risk factors.

Transverse sinus pathologies, vestibular migraine and intracranial hypertension without papilledema.

BACKGROUND: In the absence of papilledema, the presentation of migraine and idiopathic intracranial hypertension (IIH) is very similar. In this respect, an IIH could be presented as a vestibular migraine. Our main objective in this case report is to demonstrate the similarities between IIH and vestibular migraine. CASES: This is a report of 14 patients who have IIH without papilledema presented as vestibular migraine to the clinic and followed from 2020 to 2022. RESULTS: The common presentation of patients was ear-facial pain, dizziness, and frequent pulsatile tinnitus. One-fourth of the patients reported episodes of true episodic vertigo. The average age was 37.8, the average BMI was 37.4, and the average lumbar puncture-opening pressure was 25.6 cm H2O. Transverse sinus venous flow alterations caused neuroimaging findings of sigmoid sinus dehiscence, empty sella, or tonsillar ectopia. Most patients improved with carbonic anhydrase inhibitors, and one patient was treated with a dural sinus stent. CONCLUSION: A transverse sinus stenosis, even in the non-dominant site, may elevate the CSF pressure in obese individuals. This stenosis causes dural sinus-related pulsatile tinnitus with characteristics different from those of an arterial origin. Dizziness is a common complaint in patients with IIH, just like VM. In our opinion, episodic vertigo in these patients is the direct effect of CSF flow alterations into the inner ear's vestibule. Patients with mild elevations will be presented to the clinic, similar to migraines with or without the presence of pulsatile tinnitus. Treatment requires lowering intracranial pressure and managing migraine symptoms.

Intracranial arteriovenous shunts in infants: A decade of experience from a quaternary pediatric center.

BACKGROUND AND PURPOSE: Intracranial arteriovenous shunts (IAVS) are rare vascular diseases in infants. They can be categorized into vein of Galen aneurysmal malformation (VGAM), pial arteriovenous fistula (PAVF), and dural arteriovenous fistula associated with dural sinus malformation (DAVF/DSM). We sought to review the clinical presentation, imaging characteristics, endovascular treatment (EVT), and outcomes of IAVS in infants presenting to a quaternary pediatric referral center over one decade. METHODS: A retrospective review of a prospectively maintained database was performed of all infants diagnosed with IAVS between January 2011 and January 2021 in a quaternary pediatric referral center. For each patient, demographic data, clinical presentation, imaging findings, management strategies, and outcomes were reviewed and discussed. RESULTS: Over the study period, 38 consecutive infants were diagnosed with IAVS. Patients with VGAM (23/38, 60.5%) presented with congenital heart failure (CHF) (14/23), hydrocephalus (4/23), and seizures (2/23), and three patients were asymptomatic. Eighteen patients with VGAM underwent EVT. Among those, 13 patients (72.2%) were successfully treated with an angiographic cure and three patients (3/18, 17%) died. Patients with PAVF (9/38, 23.7%) presented with CHF (5/9), intracranial hemorrhage (2/9), and seizures (2/9), and all of them were successfully treated endovascularly. Patients with Type I DAVF/DSM (4/6, 66.6%) presented with mass effect (2/4), cerebral venous hypertension (1/4), CHF (1/4), and cerebrofacial venous metameric syndrome (1/4). Patients with type II DAVF/DSM (2/6, 33.3%) presented with a thrill behind the ear. Patients with DAVF/DSM were treated endovascularly, five patients were cured, and one with type I DAVF/DSM died. CONCLUSION: Intracranial arteriovenous shunts are rare but potentially life-threatening neurovascular pathologies in infants. Endovascular treatment is challenging but feasible in carefully selected patients.

Utility of 3D T1-weighted turbo spin echo black blood sequence for the diagnosis of cerebral venous thrombosis.

PURPOSE: Accurate assessment of dural sinus, deep and cortical venous thrombosis on MR imaging is challenging. The aim of this study is to evaluate the accuracy of 3D-T1 turbo spin echo (T1S), sequences in detecting venous thrombosis and comparing it with susceptibility-weighted imaging (SWI), magnetic resonance venography (MRV) and post contrast T1 magnetization-prepared rapid acquisition gradient echo (T1C). METHODS: A blinded retrospective observational analysis of 71 consecutive patients evaluated for cerebral venous thrombosis (CVT) and 30 control patients was performed. Multimodality reference standard adopted included T1C, SWI with MRV. Sub-analyses in superficial, deep and cortical venous segments were performed in addition to correlation of signal intensity of thrombus with the clinical stage. RESULTS: A total of 2222 segments in 101 complete MRI examinations were evaluated. Sensitivity/specificity/positive predictive value/negative predictive value/accuracy and precision of T1S for detection of cortical vein thrombosis was 0.994/1/1/0.967/0.995/1, 1/0.874/0.949/1/0.963/0.950 for detection of superficial venous sinus thrombosis and 1/1/1/1/1/1 for deep venous thrombosis. The AUC yield for T1S was 0.997 for cortical, 1 for deep and 0.988 for superficial venous segments. CONCLUSION: T1S paralleled the accuracy of conventional sequences in the overall detection of CVT but showed superior accuracy in the detection of cortical venous thrombosis. It makes a fitting addition to the CVT MRI protocol in scenarios demanding negation of gadolinium administration.