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

Abstract

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.Level of Evidence1Technical Efficacy Stage2

Clinical and Radiological Characteristics of Non-Obese Female Patients with Idiopathic Intracranial Hypertension

“…In our study, transverse-sigmoid stenosis was found to be severe in both groups. As in many other studies, these results highlight the importance of venous stenosis in the patho-mechanism of IIH [ 17 , 21 , 22 ]. In some studies, obesity is mentioned as a possible trigger or ameliorating factor for venous stenosis [ 21 , 23 , 24 ].…”

“…As in many other studies, these results highlight the importance of venous stenosis in the patho-mechanism of IIH [ 17 , 21 , 22 ]. In some studies, obesity is mentioned as a possible trigger or ameliorating factor for venous stenosis [ 21 , 23 , 24 ]. However, we found the non-obese population to have a very high degree of venous stenosis, suggesting that venous stenosis may not necessarily be caused or influenced by obesity.…”

VICTR: Venous transit time imaging by changes in T1 relaxation

“…However, to date, a technique does not exist to measure the VTT. It is plausible that our ability to measure this parameter will open new avenues of research in vessel properties (e.g., dilation and tortuosity 23 ) and diseases (e.g., cerebral small vessel disease, 9,21 stroke, 25 idiopathic intracranial hypertension, 50 malformation of venous vasculature 23 ). Another MRI technique, reverse perfusion imaging, was recently proposed to probe venous physiology 51,52 .…”

Reversible Bilateral Transverse Sinus Occlusion Treated by Lumboperitoneal Shunt in Idiopathic Intracranial Hypertension: A Case Report

“…These factors form a vicious circle. 14 ) Extrinsic stenosis of the venous sinus is not considered an independent cause of IIH. 14 ) Similarly, in the present case, the venous sinus obstruction is related to intrinsic and extrinsic factors.…”

“… 14 ) Extrinsic stenosis of the venous sinus is not considered an independent cause of IIH. 14 ) Similarly, in the present case, the venous sinus obstruction is related to intrinsic and extrinsic factors. Venous sinus stenting can stop this vicious circle, but it must be ineffective to the primary cause.…”