Cerebral venous sinus thrombosis and stenosis in pseudotumor cerebri syndrome

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

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

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.

Cerebral venous sinus thrombosis as a consequence of shunt hyperdrainage: a proposal of the pathophysiological mechanism and case report

BACKGROUND AND AIM

Shunt dysfunction is a common event, especially in children who have this intervention performed early in life. The consequences of chronic shunt overdrainage can be multiple since the cerebral hydrodynamics is altered. A thrombotic event with consequent symptoms of intracranial hypertension is discussed in this article.

MATERIAL AND METHODS

We performed a detailed review of cerebral hydrodynamics and intracranial pressure compensation mechanisms and how this can alter cerebral venous circulation. Next, we report the case of a 4-year-old child with such a clinical presentation that was conducted by our team.

RESULTS

A child with a history of hydrocephalus treated with a ventriculo-peritoneal (VP) shunt in his early childhood presented with symptoms of intracranial hypertension, initial computed tomography (CT) demonstrating reduced-sized ventricles. Complementary investigation showed bilateral papilledema, cranial suture closure, changes compatible with Chiari type I, and venous sinus thrombosis (transverse and sigmoid, bilaterally). The case was managed conservatively with full anticoagulation with enoxaparin. Four months after the onset of symptoms, there was an improvement in the clinical and imaging status.

CONCLUSION

A condition of severe headache in a patient with an apparently functioning shunt and small ventricles on initial CT should open up a range of diagnostic possibilities, with pseudotumor cerebri syndrome and cerebral venous sinus thrombosis being suggested. The therapeutic approach in these cases must be individualized.

Efficacy of stenting in patients with cerebral venous sinus thrombosis-related cerebral venous sinus stenosis

BACKGROUND

Venous stenting has been proven to be a safe and effective therapeutic option for patients with idiopathic intracranial hypertension (IIH) and cerebral venous sinus stenosis (CVSS). However, its use in patients with cerebral venous sinus thrombosis-related CVSS has been less reported.

PURPOSE

To explore the safety and efficacy of stenting for patients with cerebral venous sinus thrombosis (CVST)-related CVSS.

METHODS

The clinical presentation, treatment, and outcome of patients with CVST-related CVSS received venous stenting in the chronic stage after failed medical treatment were retrospectively evaluated.

RESULTS

A total of 17 patients with CVST-related CVSS were included. Mean pressure gradient across the CVSS decreased from 11.5±4.2 mmHg prior to stenting to 2.1±1.1 mmHg post- stenting. Mean CSF opening pressure decreased from 33.1±5.5 cmH₂O to 18.7±1.7 cmH₂O. Both headache and visual disturbance improved or resolved in 78% and 92% of the patients, respectively. Complications included lethal cerebellar hematoma in one case and bilateral occipital epidural hematoma in another case. One of the patients received retreatment with ventriculo-peritoneal shunting due to recurrent headache.

CONCLUSION

Restoring the patency of stenotic sinuses with stents in patients of CVST-related CVSS unresponsive to medical therapy in the chronic stage may improve symptoms in the majority of the patients. However, a relatively higher cerebral hemorrhage rate was observed and may be related to this pathology. Stenting in this subgroup of CVSS patients may require further evaluation with a larger and long-term study, and should be used with caution at this time.

Idiopathic Intracranial Hypertension Progressing to Venous Sinus Thrombosis, Subarachnoid Hemorrhage, and Stroke

Idiopathic intracranial hypertension (IIH) is a syndrome characterized by increased intracranial pressure (ICP), the absence of structural lesions on neuroimaging, and normal cerebrospinal fluid composition. Cerebral venous sinus thrombosis (CVST) is a common cause of increased ICP and can be differentiated from IIH with magnetic resonance venography. We describe a young woman with typical IIH who underwent lumbar puncture and was treated with a short course of high-dose corticosteroids followed by acetazolamide. She subsequently developed CVST, subarachnoid hemorrhage, and stroke. Risk factors that may have resulted in CVST are discussed.

Optic Nerve

Optic nerve diseases arise from many different etiologies including inflammatory, neoplastic, genetic, infectious, ischemic, and idiopathic. Understanding some of the characteristics of the most common optic neuropathies along with therapeutic approaches to these diseases is helpful in designing recommendations for individual patients. Although many optic neuropathies have no specific treatment, some do, and it is those potentially treatable or preventable conditions which need to be recognized in order to help patients regain their sight or develop a better understanding of their own prognosis. In this chapter several diseases are discussed including idiopathic intracranial hypertension, optic neuritis, ischemic optic neuropathies, hereditary optic neuropathies, trauma, and primary tumors of the optic nerve. For each condition there is a presentation of the signs and symptoms of the disease, in some conditions the evaluation and diagnostic criteria are highlighted, and where possible, current therapy or past trials are discussed.