Cause or Consequence: The Relationship Between Cerebral Venous Thrombosis and Idiopathic Intracranial Hypertension

A narrative review of magnetic resonance imaging findings in pediatric idiopathic intracranial hypertension

Background and Aims

Idiopathic intracranial hypertension (IIH) is a rare neurological disorder in the pediatric population which is defined as an increase in intracranial pressure (ICP) without the presence of brain parenchymal lesions, hydrocephalus, or central nervous system infection. In this study, we have determined the magnetic resonance imaging (MRI) findings in IIH patients.

Methods

A comprehensive literature search was conducted using the electronic databases including Web of Sciences, Scopus, and Pubmed to identify suitable and relevant articles using keyword search methods. The search included keywords such as "idiopathic intracranial hypertension," "pseudotumor cerebri," "MRI," and "pediatrics." The search was limited to the available publications up to January 2024.

Results

MRI plays a crucial role in diagnosing IIH by excluding secondary causes and revealing neuroimaging findings associated with elevated ICP. Despite fewer studies in children compared to adults, MRI serves as a cornerstone in identifying traditional neuroradiological markers such as empty sella turcica, posterior globe flattening, optic nerve tortuosity, optic nerve sheath distension, and transverse venous sinus stenosis. Additional subtle markers include increased Meckel's cave length, cerebellar tonsillar herniation, and slit-like ventricles, although these are less reliable. Diffusion-weighted imaging does not typically show cerebral ADC value changes indicative of cerebral edema in pediatric IIH.

Conclusion

MRI findings provide valuable non-invasive diagnostic indicators that facilitate early detection, clinical management, and potential surgical intervention in pediatric IIH. The reliability of these MRI markers underscores their importance in clinical practice.

Current and emerging diagnostic and management approaches for idiopathic intracranial hypertension

INTRODUCTION

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

AREAS COVERED

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

EXPERT OPINION

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

Venous Sinus Thrombosis in the Hypoglossal Canal Mimics a Neurogenic Tumor in a Patient with Presumed Idiopathic Intracranial Hypertension: A Case Report

Presumed idiopathic intracranial hypertension (IIH) is a disorder of elevated intracranial pressure with unknown etiology, and 10% of cases occur secondarily to cerebral venous sinus thrombosis (CVST). CVST may be underestimated when findings of IIH are missed in a normal-weight patient without risk factors of coagulopathy. Here, we present a case of CVST that mimics a neurogenic tumor in the hypoglossal canal in a normal-weight patient without risk factors of coagulopathy.

Chronic intracranial hypertension after cerebral venous and sinus thrombosis - frequency and risk factors

BACKGROUND

Cerebral venous sinus thrombosis (CVST) can infrequently lead to chronical intracranial hypertension (IH) due to the altered venous drainage. The aim of this study was to ascertain the risk of IH after CVST and to stratify underlying risk factors.

METHODS

We performed a retrospective cohort analysis of all cases treated for acute CVST at our department between 2013 and 2019. IH was diagnosed at follow-up according to the modified Dandy criteria. CVST-patients with and without IH were descriptively compared conforming to available clinical and radiological data as well as outcomes.

RESULTS

Our study included 102 patients with acute CVST. In 70 cases complete follow-up data was available (68.6%). Seven of these patients developed symptomatic intracranial hypertension (10%; N = 7, n = 70) within a median follow-up of 6 months. Four of these patients (57.1% (N = 4, n = 7) vs. 3.2% (N = 2, n = 63); p < 0.001) presented recurrent sinus thrombosis in the further course. There were no significant differences between patients with or without IH concerning gender, age, risk factors, occluded vessels and treatment for their CVST. However the presence of visual deterioration at initial admission was higher in patients who developed IH afterwards (57.1% (N = 4, n = 7) vs. 20.6% (N = 13, n = 63); p = 0.03). Patients with chronic IH after CVST showed significantly less likely recanalization of the occluded vessel on follow-up MRI (no recanalization in 28.6% (N = 2, n = 7) vs. 4.8% (N = 3, n = 63); p = 0.02). All patients with IH had a good outcome (mRS 0-2) at discharge and follow-up.

CONCLUSION

IH occurred in around 10% after CVST. Insufficient recanalization status may facilitate IH. Patients with visual disturbances seem to develop more likely IH afterwards. Patients who present IH after CVST may develop recurrent cerebral venous thrombosis.

Cerebral venous thrombosis: Diagnosis and management in the emergency department setting

INTRODUCTION

Cerebral venous thrombosis (CVT) is an uncommon neurologic emergency associated with significant morbidity and mortality that can be difficult to differentiate from other conditions. It is important for the emergency clinician to be familiar with this disease as it requires a high index of suspicion, and early diagnosis and management can lead to improved outcomes.

OBJECTIVE

This narrative review provides an evidence-based update concerning the presentation, evaluation, and management of CVT for the emergency clinician.

DISCUSSION

CVT is due to thrombosis of the cerebral veins resulting in obstruction of venous outflow and increased intracranial pressure. Early recognition is important but difficult as the clinical presentation can mimic more common disease patterns. The most common patient population affected includes women under the age of 50. Risk factors for CVT include pregnancy, medications (oral contraceptives), inherited thrombophilia, prior venous thromboembolic event, malignancy, recent infection, and neurosurgery. CVT can present in a variety of ways, but the most common symptom is headache, followed by focal neurologic deficit, seizure, and altered mental status. Imaging studies such as computed tomography (CT) venography or magnetic resonance (MR) venography should be obtained in patients with concern for CVT, as non-contrast CT will be normal or have non-specific findings in most patients. Treatment includes anticoagulation, treating seizures and elevated ICP aggressively, and neurosurgical or interventional radiology consultation in select cases.

CONCLUSIONS

CVT can be a challenging diagnosis. Knowledge of the risk factors, patient presentation, evaluation, and management can assist emergency clinicians.

Venous Sinus Stenosis Treatment in Pediatric Idiopathic Intracranial Hypertension: Illustrative Case and Literature Review

OBJECTIVE

To review the literature of venous sinus stenosis (VSS) treatment in children for idiopathic intracranial hypertension (IIH) and present our own institutional case.

METHODS

A literature review was conducted using the PubMed and MEDLINE databases up to June 2020. From 134 studies that were screened, 6 studies were chosen for analysis that included patients <18 years old, a diagnosis of IIH that fit Dandy diagnostic criteria, and angiogram obtained to assess for VSS. IIH symptoms experienced in the pediatric population and efficacy of venous sinus stenting were analyzed.

RESULTS

Eleven patients identified in the literature and 1 patient from our institution were included in the analysis. There was no statistically significant difference in pressure gradient response to stenting between male and female patients (P = 0.424) or patients with body mass index >90th percentile (P = 0.626). Larger decreases in pressure gradient after stent placement correlated with headache resolution (P = 0.0005). Patients who underwent unilateral stenting showed greater reduction in pressure gradient compared with patients who underwent bilateral stenting (average change 24 mm Hg vs. 5.75 mm Hg, P = 0.003).

CONCLUSIONS

Our analysis showed that VSS treatment has the potential to be a safe option for IIH in pediatric patients. VSS treatment has shown similar results to traditional cerebrospinal fluid diversion procedures, with a lower complication rate and need for revision. More studies should be conducted to analyze the long-term efficacy and safety of VSS treatment in pediatric patients with IIH.

Cerebral Venous Thrombosis: Review of Diagnosis, Follow-Up, Late Complications and Potential Pitfalls

Cerebral venous thrombosis is a less common but relevant cause of stroke in adults. The clinical manifestations are nonspecific leading frequently diagnostic delays, so imaging findings are is of vital importance. Conventional imaging modalities, namely computed tomography and magnetic resonance imaging (MRI), allow identification of the thrombus and parenchymal involvement due to venous congestion to a variable degree, but this entity may appears as a nonexpected finding in a nonvenographic study. computed tomography and MRI venographies allow noninvasive confirmation of the diagnosis and adequate characterization of the extent of the thrombus and acute complications, both of them being robust diagnostic techniques. MR venography also can be done without the use of contrast media, which is especially important in certain clinical situations. Cerebral venous thrombosis needs follow-up, and imaging plays a key role in detection of late complications of the disease, including dural arteriovenous fistulas and intracranial hypertension due to veno-occlusive disease. Knowledge of other diseases and conditions that may mimic a thrombus is needed to avoid wrong diagnosis. In this article, we conduct a pictorial comprehensive review of cerebral venous thrombosis, including also the technical aspects of different imaging modalities, diagnosis and acute complications, follow-up, late complications and potential imaging mimics.

An update on idiopathic intracranial hypertension in adults: a look at pathophysiology, diagnostic approach and management

Idiopathic intracranial hypertension is a neurological syndrome determined by a rise in intracranial pressure without a detectable cause. Course and prognosis may be changeable, requiring a multidisciplinary approach for its diagnosis and management. Although its precise pathogenesis is still unknown, many studies have been carried out to define the possible causal and associated factors, such as retinoids, steroid hormones, body mass index and recent weight gains, cytokines and adipokines levels. The clinical presentation can be variable including chronic headache, disturbance of vision, diplopia and tinnitus. Even if papilloedema is considered the most specific sign, it could not be observed in more than 5% of patients during the evaluation of the fundus oculi. Neuroradiological signs acquire greater importance in patients who do not present papilloedema and may suggest the diagnosis of idiopathic intracranial hypertension. Other assessments can be useful in the diagnostic process, such as optical coherence tomography, visual evoked potentials, ocular ultrasonography and fundus fluorescein angiography and autofluorescence. Nonetheless, cerebrospinal fluid pressure measurement is required to establish a definite diagnosis. Management may be different, since surgical procedures or lumbar punctures are often required when symptoms develop rapidly leading to a loss of visual function. Apart from these cases, patients can be treated with a pharmacological approach and low-calorie diet, but they also need to be monitored over time since relapses years later are not uncommon.