Subarachnoid Hemorrhage Following Angioplasty and Stenting in a Patient with Primitive Drainage Pattern of the Basal Vein of Rosenthal.

Severe visual loss may occur in patients with pseudotumor cerebri (PTC), also known as idiopathic intracranial hypertension. Transverse sinus stenosis is 1 cause of PTC syndrome. Although the role of transverse sinus stenosis in the pathogenesis of the disease remains controversial, recent case series of transverse sinus stenting have reported very high rates of symptom response and resolution of papilledema with improvement or at least stabilization of the visual fields and visual acuity (Ahmed et al., 2011).1 We report a previously unpublished complication of diffuse, nonaneurysmal subarachnoid hemorrhage following angioplasty and stenting in a patient with refractory PTC.

Patterns of chronic venous insufficiency in the dural sinuses and extracranial draining veins and their relationship with white matter hyperintensities for patients with Parkinson's disease.

BACKGROUND: Idiopathic Parkinson's disease (IPD) remains one of those neurodegenerative diseases for which the cause remains unknown. Many clinically diagnosed cases of IPD are associated with cerebrovascular disease and white matter hyperintensities (WMHs). The purpose of this study was to investigate the presence of transverse sinus and extracranial venous abnormalities in IPD patients and their relationship with brain WMHs. METHODS: Twenty-three IPD patients and 23 age-matched normal controls were recruited in this study. They had conventional neurologic magnetic resonance structural and angiographic scans and, for blood flow, quantification of the extracranial vessels. Venous structures were evaluated with two-dimensional time of flight; flow was evaluated with two-dimensional phase contrast; and WMH volume was quantified with T2-weighted fluid-attenuated inversion recovery. The IPD and normal subjects were classified by both the magnetic resonance time-of-flight and phase contrast images into four categories: (1) complete or local missing transverse sinus and internal jugular veins on the time-of-flight images; (2) low flow in the transverse sinus and stenotic internal jugular veins; (3) reduced flow in the internal jugular veins; and (4) normal flow and no stenosis. RESULTS: Broken into the four categories with categories 1 to 3 combined, a significant difference in the distribution of the IPD patients and normal controls (χ(2) = 7.7; P < .01) was observed. Venous abnormalities (categories 1, 2, and 3) were seen in 57% of IPD subjects and in only 30% of controls. In IPD subjects, category type correlated with both flow abnormalities and WMHs. CONCLUSIONS: From this preliminary study, we conclude that a major fraction of IPD patients appear to have abnormal venous anatomy and flow on the left side of the brain and neck and that the flow abnormalities appear to correlate with WMH volume. Studies with a larger sample size are still needed to confirm these findings.

Venous hypertension as the cause of intracranial hypertension in patients with transverse sinus dural arteriovenous fistula.

We describe 2 patients with transverse sinus dural arteriovenous fistulas (DAVFs) who presented with headache and papilledema due to intracranial hypertension. It has been proposed, but never proven, that venous hypertension causes the intracranial hypertension in DAVF. The data from our patients support this hypothesis. An additional factor leading to intracranial hypertension could be stenosis of the fellow transverse sinus.

Reductions in bilateral transverse sinus pressure gradients with unilateral transverse venous sinus stenting for idiopathic intracranial hypertension.

BACKGROUND: Venous sinus stenting is an effective treatment for papilledema associated with idiopathic intracranial hypertension (IIH). It is unclear whether unilateral transverse-sigmoid sinus (TSS) stenting adequately decompresses the contralateral TSS system in cases of bilateral transverse sinus stenosis. The objective of this study was to compare changes in bilateral TSS pressure gradients following unilateral TSS stenting in a series of patients with IIH. METHODS: Consecutive patients from a single institution who underwent venous sinus stenting for IIH with measurement of bilateral pressure gradients before and after stenting for IIH were enrolled. Pressure gradients in both TSS pre- and post-stenting were measured during the procedure. The TSS with the highest gradient was stented. Changes in TSS pressure gradients following stent placement were calculated for both TSS. Mean changes in pressure gradients of ipsilateral and contralateral TSS were calculated. RESULTS: Sixteen patients with IIH who underwent TSS stenting were included. All were female. Mean age was 36.4 years. The right-sided TSS was the stented side in 12 (75.0%) patients. The mean pre-stent pressure gradient of the ipsilateral TSS was 19.3 mmHg (SD=10.8), which was reduced to a mean of 3.8 mmHg (3.4) following stent placement (P =<0.0001). On the contralateral (non-stented) side, the mean pre-stent gradient of 15.1 mmHg (7.5) was reduced to a mean of 7.8 mmHg (6.6) following stenting (P=0.006). CONCLUSIONS: The use of a single stent provides some venous decompression of the contralateral non-stented stenosis in most cases of IIH treated with endovascular therapy.

Venous sinus stenting lowers the intracranial pressure in patients with idiopathic intracranial hypertension.

AIMS: We report the cerebrospinal fluid opening pressure (CSF-OP) measurements obtained before and after venous sinus stenting (VSS) in 50 patients with idiopathic intracranial hypertension. METHODS: The CSF-OP was measured with a spinal tap 3 months before and 3 months after treatment. All data were prospectively collected and included patient demographics, weight (kg), body mass index (BMI), acetazolamide daily dosage (mg), procedural details, complications, venous sinus pressures (mm Hg), trans-stenotic pressure gradient (mm Hg), transverse sinus symmetry, and type of venous sinus stenosis. RESULTS: The average pretreatment CSF-OP was 37 cm H2O (range 25-77) and the average post-treatment CSF-OP was 20.2 cm H2O (range 10-36), with an average reduction of 16.8 cm H2O (P<0.01). The post-treatment CSF-OP was less than 25 cm H2O in 40/50 patients. The average acetazolamide daily dose decreased from 950 mg to 300 mg at the time of 3-month follow-up (P<0.01). No patient required an increase in acetazolamide dose 3 months after VSS. The average weight before treatment was 95.4 kg with an average BMI of 35.41. There was an average increase in body weight of 1.1 kg at the 3-month follow-up with an average increase in BMI of 0.35 (P=0.03). CONCLUSIONS: We provide evidence that there is a significant decrease in CSF-OP in patients with idiopathic intracranial hypertension 3 months after VSS, independent of acetazolamide usage or weight loss.

Reduced Jet Velocity in Venous Flow after CSF Drainage: Assessing Hemodynamic Causes of Pulsatile Tinnitus.

BACKGROUND AND PURPOSE: Idiopathic intracranial hypertension is commonly associated with transverse sinus stenosis, a venous cause of pulsatile tinnitus. In patients with idiopathic intracranial hypertension, CSF drainage via lumbar puncture decreases intracranial pressure, which relieves the stenosis, and may provide at least temporary cessation of pulsatile tinnitus. The objective of this study was to evaluate changes in venous blood flow caused by lowered intracranial pressure in patients with pulsatile tinnitus to help identify the cause of pulsatile tinnitus. MATERIALS AND METHODS: Ten patients with suspected transverse sinus stenosis as a venous etiology for pulsatile tinnitus symptoms underwent MR imaging before and after lumbar puncture in the same session. The protocol included flow assessment and rating of pulsatile tinnitus intensity before and after lumbar puncture and MR venography before lumbar puncture. Post-lumbar puncture MR venography was performed in 1 subject. RESULTS: There was a lumbar puncture-induced reduction in venous peak velocity that correlated with the opening pressure (r = -0.72, P = .019) without a concomitant reduction in flow rate. Patients with flow jets had their peak velocity reduced by 0.30 ± 0.18 m/s (P = .002), correlating with a reduction in CSF pressure (r = 0.82, P = .024) and the reduction in subjectively scored pulsatile tinnitus intensity (r = 0.78, P = .023). The post-lumbar puncture MR venography demonstrated alleviation of the stenosis. CONCLUSIONS: Our results show a lumbar puncture-induced reduction in venous peak velocity without a concomitant reduction in flow rate. We hypothesize that the reduction is caused by the expansion of the stenosis after lumbar puncture. Our results further show a correlation between the peak velocity and pulsatile tinnitus intensity, suggesting the flow jet to be instrumental in the development of sound.

Cerebral venous blood flow in growth restricted fetuses with an abnormal blood flow in the umbilical artery before 32 weeks of gestation.

OBJECTIVE: To evaluate the brain venous circulation in fetuses with severe intrauterine growth restriction (IUGR) before 32 weeks of gestation. STUDY DESIGN: Fifty fetuses with severe IUGR diagnosed between 27 and 32 weeks of gestation and 50 appropriate-for-gestational age (AGA) fetuses matched by gestational age were evaluated. IUGR fetuses were classified according to their hemodynamic deterioration pattern in relation to the Doppler examination of the umbilical artery (UA), middle cerebral artery (MCA) and ductus venosus (DV). The fetal venous brain blood flow was evaluated in the vein of Galen (VG), superior sagittal (SS), straight and transverse venous sinuses. RESULTS: Only the transverse sinus (TS) showed a significant reduction in the pulsatility index (PI) values in IUGR fetuses. All other veins showed similar PI values between IUGR and AGA fetuses. All cerebral veins of IUGR fetuses showed significantly increased maximum and mean velocities. All these findings did not change in relation to the hemodynamic IUGR deterioration. In nearly all normal and all IUGR fetuses, a pulsatile blood flow pattern was observed in the straight and transverse sinuses, whereas an increased pulsatile pattern in the VG and in the SS was noted in IUGR fetuses. CONCLUSION: Brain venous blood flow in IUGR fetuses shows an increment in the maximum and mean velocities of all veins and a reduction in the PI in the transverse sinus.

Venous collateral drainage patterns predict clinical worsening in dural venous sinus thrombosis.

BACKGROUND: Dural venous sinus thrombosis (DVST) is an increasingly recognized cause of a wide array of neurological symptoms, with outcomes that range from complete recovery to death. The condition of approximately 23% of patients with DVST will worsen after initial presentation, as a result of restricted venous outflow and venous hypertension, but early identification of this subset is challenging. A venous collateral scale (VCS) that grades alternative drainage routes may improve prediction of clinical deterioration. OBJECTIVE: To examine the ability of the VCS system to accurately identify patients with DVST who will experience clinical worsening, based on their imaging at presentation. METHODS: From our institutional database, we identified patients with DVST on dedicated venous imaging between January 2010 and July 2016. A VCS was created and calculated from venous imaging at presentation by two reviewers blinded to subsequent data. RESULTS: The 27 patients who met the inclusion criteria for this study had a median age of 42 years and 14 (52%) were female. Initial symptoms included headache without hemorrhage in 30% and focal deficit in 30%. Transverse sinus occlusion was present in 70% and superior sagittal sinus occlusion in 41%. VCS was 0 in 11%, 1 in 37%, and 2 in 52%. A lower VCS was significantly associated with clinical worsening both from time of initial symptom onset (77% vs 29%, VCS 0-1 vs 2, p<0.05) and during hospitalization (62% vs 0%, VCS 0-1 vs 2, p<0.01). In multivariate analysis, VCS but no other presenting features was significantly associated with in-hospital worsening (OR=2, p<0.01). CONCLUSIONS: The type and quality of venous collaterals influence outcome in DVST. VCS helps to identify patients whose condition is likely to deteriorate and may need additional aggressive interventions.

Pattern of pressure gradient alterations after venous sinus stenting for idiopathic intracranial hypertension predicts stent-adjacent stenosis: a proposed classification system.

OBJECTIVE: Venous sinus stenting (VSS) is a safe and effective treatment for idiopathic intracranial hypertension (IIH) with angiographic venous sinus stenosis. However, predictors of stent-adjacent stenosis (SAS) remain poorly defined. METHODS: We performed a retrospective review of 47 patients with IIH and intracranial venous stenosis who underwent VSS with pre- and post-stent venography. Patient characteristics, treatments and outcomes were reviewed. Changes in pressure gradient after VSS were classified according to pattern of gradient resolution into types I-III. RESULTS: Type I gradient resolution, in which mean venous pressure (MVP) in the transverse sinus (TS) decreases towards MVP in the sigmoid sinus (SS), occurred in 18 patients (38.3%). Type II gradient resolution pattern, in which SS MVP increases towards that in the TS, occurred in 7patients (14.9%). Type III pattern, in which MVP equilibrates to a middle value, occurred in 22patients (46.8%). SAS occurred in 0%, 28.6%, and 22.7% of patients in types I, II and III, respectively. Compared with patients with type I gradient resolution, SAS was more common in those with type II (p=0.0181) and type III (p=0.0306) patterns. CONCLUSIONS: The pattern of change in the trans-stenosis venous pressure gradient may be predictive of SAS and is a useful tool for classifying the response of the venous obstruction to stenting. A type I pattern appears to represent the ideal response to VSS. Some patients with type II and III changes, particularly if they have other predictors of recurrent stenosis, may benefit from longer initial stent constructs.

Quantifying the Cerebral Hemodynamics of Dural Arteriovenous Fistula in Transverse Sigmoid Sinus Complicated by Sinus Stenosis: A Retrospective Cohort Study.

BACKGROUND AND PURPOSE: Sinus stenosis occasionally occurs in dural arteriovenous fistulas. Sinus stenosis impedes venous outflow and aggravates intracranial hypertension by reversing cortical venous drainage. This study aimed to analyze the likelihood of sinus stenosis and its impact on cerebral hemodynamics of various types of dural arteriovenous fistulas. MATERIALS AND METHODS: Forty-three cases of dural arteriovenous fistula in the transverse-sigmoid sinus were reviewed and divided into 3 groups: Cognard type I, type IIa, and types with cortical venous drainage. Sinus stenosis and the double peak sign (occurrence of 2 peaks in the time-density curve of the ipsilateral drainage of the internal jugular vein) in dural arteriovenous fistula were evaluated. "TTP" was defined as the time at which a selected angiographic point reached maximum concentration. TTP of the vein of Labbé, TTP of the ipsilateral normal transverse sinus, trans-fistula time, and trans-stenotic time were compared across the 3 groups. RESULTS: Thirty-six percent of type I, 100% of type IIa, and 84% of types with cortical venous drainage had sinus stenosis. All sinus stenosis cases demonstrated loss of the double peak sign that occurs in dural arteriovenous fistula. Trans-fistula time (2.09 seconds) and trans-stenotic time (0.67 seconds) in types with cortical venous drainage were the most prolonged, followed by those in type IIa and type I. TTP of the vein of Labbé was significantly shorter in types with cortical venous drainage. Six patients with types with cortical venous drainage underwent venoplasty and stent placement, and 4 were downgraded to type IIa. CONCLUSIONS: Sinus stenosis indicated dysfunction of venous drainage and is more often encountered in dural arteriovenous fistula with more aggressive types. Venoplasty ameliorates cortical venous drainage in dural arteriovenous fistulas and serves as a bridge treatment to stereotactic radiosurgery in most cases.

Computational Fluid Dynamics Simulation of Hemodynamic Alterations in Sigmoid Sinus Diverticulum and Ipsilateral Upstream Sinus Stenosis After Stent Implantation in Patients with Pulsatile Tinnitus.

OBJECTIVE: To investigate the relationships between upstream venous sinus stenosis and pulsatile tinnitus (PT), and to assess the correlation with diverticulum growth and the effectiveness of stent implantation. METHODS: Patient-specific geometric models were constructed using computed tomography venography images from a patient with PT, with sigmoid sinus diverticulum, and with upstream transverse sinus stenosis, in whom stenting of the upstream sinus stenosis alone achieved complete remission of PT. Computational fluid dynamics simulation based on this patient-specific geometry was performed using commercially available finite element software (ANSYS-14) to qualitatively and quantitatively compare the flow velocity, flow rate, velocity vector, pressure, vorticity, and wall shear stress on the affected side transverse and sigmoid sinuses, before and after stent implantation. RESULTS: Stenting improved the flow direction and magnitude. After stenting, the flow pattern became smoother and more regular. High-speed blood flow at the level of the diverticulum neck was confined to a smaller area, and its direction changed from approximately perpendicular to the diverticular dome to the distal side of the diverticular neck. The diverticulum showed obvious flow reduction, with decreases of 80.7%, 68.7%, 96.1%, and 91.3% in peak velocity, inflow rate, pressure gradient, and peak vorticity, respectively. The abnormally low wall shear stress at the dome of diverticulum was eliminated. CONCLUSIONS: Our findings strongly support a major role of diverticulum stenosis before in PT development and suggest that such stenosis is a causative factor of diverticulum growth. They also confirm the effectiveness of stent implantation for the treatment of PT.

Diagnosis of Transverse Sinus Hypoplasia in Magnetic Resonance Venography: New Insights Based on Magnetic Resonance Imaging in Combined Dataset of Venous Outflow Impairment Case-Control Studies: Post Hoc Case-Control Study.

In previous studies of transverse sinus (TS) hypoplasia, discrepancies between TS diameter measured by magnetic resonance venography (MRV) and contrast T1-weighted magnetic resonance (contrast T1) were observed. To investigate these discrepancies, and considering that TS hypoplasia is associated with neurological disorders, we performed a post hoc analysis of prospectively collected data from 3 case-control studies on transient global amnesia (TGA), transient monocular blindness (TMB), and panic disorders while retaining the original inclusion and exclusion criteria. Magnetic resonance (MR) imaging of 131 subjects was reviewed to evaluate TS diameter and the location and degree of venous flow stenosis and obstruction.MRV without contrast revealed that TS hypoplasia was observed in 69 subjects, whom we classified into 2 subgroups according to the concordance with contrast T1 observations: concordance indicated anatomically small TS (30 subjects), and discrepancy indicated that the MRV diagnosis is in fact flow-related and that TS is not anatomically small (39 subjects). The latter subgroup was associated with at least 1 site of venous compression/stenosis in the internal jugular vein (IJV) or the left brachiocephalic vein (BCV) (P < 0.001), which was significantly larger in patients than controls. Compensatory dilatation of contralateral TS diameter was only observed with MRV, not with contrast T1 imaging.The clinical implication of these results is that using MRV only, IJV/BCV compression/stenosis may be misdiagnosed as TS hypoplasia. And contralateral TS have no compensatory dilatation in its diameter in contrast T1 imaging, just compensatory increased flow volume.

Does bilateral transverse cerebral venous sinus stenosis exist in patients without increased intracranial pressure?

OBJECTIVE: Transverse cerebral venous sinus stenosis (TSS) is common among patients with idiopathic intracranial hypertension. TSS likely also exists among individuals with normal intracranial pressure (ICP) but the prevalence is unclear. The goal of this study was to identify patients with incidental TSS and normal ICP and describe their characteristics. METHODS: Among 240 adult patients who underwent brain magnetic resonance imaging (MRI) with magnetic resonance venography (MRV) with contrast at our institution between September 2009 and September 2011, 44 had isolated TSS without further substantial imaging abnormality. Medical records were reviewed for symptoms of increased ICP, papilledema, cerebrospinal fluid (CSF) constituents and opening pressure (OP), and reason for brain imaging. Of these, 37 were excluded for confirmed or possible idiopathic intracranial hypertension. Of the remainder, 5 had CSF-OP≤25 cmH2O without papilledema, and 2 did not have measured ICP, but had no papilledema or symptoms of increased ICP. Imaging was re-interpreted to assess for signs suggestive of elevated ICP and to characterize the TSS further. RESULTS: All patients were women (mean age: 41, mean BMI: 37.1). CSF contents were normal, but OPs were at the upper limit of normal (22-25 cmH2O). Indications for MRI/MRV included query pituitary abnormality (1), migraine (4), and anomalous-appearing optic nerves (2). All had bilateral TSS. Six had short TSS and an empty sella; 1 had long TSS and no empty sella; 1 had flattening of the posterior sclera; 2 had prominence of peri-optic nerve CSF. CONCLUSION: Asymptomatic bilateral TSS exists in patients with ICP≤25 cmH2O, but is likely uncommon. CSF-OP was at the upper limit of normal in our patients, who also had other radiologic signs suggestive (but not specific) of chronically-raised ICP. Findings of bilateral TSS on imaging should prompt funduscopic examination for papilledema.

Changes in cerebral venous sinuses diameter after lumbar puncture in idiopathic intracranial hypertension: a prospective MRI study.

BACKGROUND: Idiopathic intracranial hypertension (IIH), is characterized by elevated intracranial pressure (ICP) without a clear cause. Recently it was shown that in more than 90% of the IIH patients there is stenosis of the transverse dural sinuses. In this study we assessed the changes in diameter of cerebral veins after lumbar puncture, in order to have some more insight regarding the volume and pressure influence on cerebral veins. METHODS: We prospectively included 13 patients suspected with IIH, admitted for investigation in the Soroka medical center. All the patients had a lumbar puncture (LP) with opening pressure measurement and CSF analysis, and two MRI-MRV studies: one before the LP and one after it. Measurements of the cerebral venous sinuses diameter were performed. RESULTS: Significant stenosis of both transverse sinuses was found before LP in IIH patients with an average diameter of 1.77 mm of the right TS, and 1.57 mm of the left TS. After the LP, there was a significant increase in all venous sinuses diameters (P < .05). There was no correlation between the changes in diameter of the venous sinuses after LP and opening pressure measured or BMI. CONCLUSIONS: Our results support other studies and demonstrated narrowing of the transverse sinuses in IIH patients. The main finding of this study is the increase in cerebral sinuses diameter after LP. This observation should be considered when evaluating cerebral venous sinuses after LP. A larger scale study is warranted to validate our findings.

Papel de la radiología en el síndrome de pseudotumor cerebral / Role of Imaging in pseudotumor cerebri syndrome

El síndrome de pseudotumor cerebral (SPTC) es una alteración caracterizada por el aumento de presión intracraneal que afecta predominantemente a mujeres jóvenes obesas. El objetivo del trabajo es definir los conceptos de SPTC primario, sin causa identificable y denominado también hipertensión intracraneal idiopática (HII), y de SPTC secundario, con etiología identificable. Se revisa el papel actual de las pruebas de imagen en su diagnóstico y los hallazgos por imagen típicos del SPTC, algunos de los cuales se incluyen entre los criterios diagnósticos propuestos en 2013. También se remarca el papel fundamental de la radiología intervencionista en el tratamiento, puesto que la colocación de stent en las estenosis de senos venosos constituye una alternativa terapéutica novedosa en pacientes resistentes al tratamiento clásico. Por último, se describen aquellos biomarcadores de imagen que han sido evaluados para aproximar el diagnóstico de la HII y predecir la respuesta al tratamiento

Pseudotumor cerebri is a disorder characterized by increased intracranial pressure that predominantly affects obese young women. This paper aims to define the concepts of primary pseudotumor cerebri, in which the cause cannot be identified (also known as idiopathic intracranial hypertension), and secondary pseudotumor cerebri, in which the cause can be identified. We review the current role of imaging techniques in diagnosing pseudotumor cerebri and describe and illustrate the most characteristic imaging findings of the disorder, some of which are included in the diagnostic criteria proposed in 2013. We also consider the fundamental role of interventional radiology in the treatment of pseudotumor cerebri because placing a stent in stenosed venous sinuses is a novel treatment option in patients who are refractory to classical treatment. Finally, we describe the imaging biomarkers that have been evaluated for diagnosing primary pseudotumor cerebri and predicting the response to treatment

Spontaneous closure of a type 2a dural arteriovenous fistula following late recanalization of the occluded sinus.

We describe the rare spontaneous resolution of a type 2a dural AVF that coincided with recanalization of the previously thrombosed sigmoid sinus after ten years of conservative management. The factors potentially responsible for spontaneous fistula obliteration are discussed and the therapeutic implication of this observation is considered.