An asymptotic method for the prediction of the anisotropic effective elastic properties of the cortical vein: superior sagittal sinus junction embedded within a homogenized cell element

Object The cerebral venous regulation involved in various physiological and pathological processes has received little attention. Here the authors describe the anatomy of the junction between the cortical vein and the superior sagittal sinus (SSS) and propose a new theory of cerebral venous regulation. Methods Ten adult human cadaveric heads (20 sides), including five specimens into which stained latex had been injected, were used for anatomical study. Formalin-fixed cadaver heads were dissected to demonstrate the cortical veins along the SSS. The characteristics of the cortical bridging veins and their openings into the SSS were established by anatomical, histological, immunohistochemical, and ultrastructural study of the junction. Results After their subarachnoid course, the cortical bridging veins penetrated the SSS at different points in the dura mater depending on their rostrocaudal position. The venous endothelium stretched beyond the sinus endothelium. The orientation of the collagen fibers changed at the level of the venous openings, with the luminal diameter becoming narrow and oval-shaped. The major finding was the organization of the smooth-muscle cells at the end of each cortical vein. At this site and particularly in the frontoparietal region, the vessel resembled a myoendothelial “sphincter.” The authors hypothesize that this organization is involved in cerebral venous system regulation. Conclusions The point of convergence between the cortical veins and the SSS is a key area. The authors also hypothesize that the myoendothelial junction acts as a smooth sphincter and that it plays a role in cerebral venous hemodynamics and pathological conditions.

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Mechanical thrombectomy and intravascular imaging for cerebral venous sinus thrombosis: a preclinical model

Journal of Neurosurgery ◽

10.3171/2020.6.jns201795 ◽

2020 ◽

pp. 1-6

Author(s):

Christopher R. Pasarikovski ◽

Jerry C. Ku ◽

Julia Keith ◽

Joel Ramjist ◽

Yuta Dobashi ◽

...

Keyword(s):

Superior Sagittal Sinus ◽

Sinus Thrombosis ◽

Cerebral Venous Sinus Thrombosis ◽

Venous Sinus ◽

Preclinical Model ◽

Endovascular Techniques ◽

Venous Sinus Thrombosis ◽

Cortical Vein ◽

Sagittal Sinus ◽

Oct Imaging

OBJECTIVEAlthough the majority of patients with cerebral venous sinus thrombosis (CVST) will improve with anticoagulation therapy, a portion of patients will either present in a comatose state or continue to deteriorate clinically despite early anticoagulation. In these cases, along with treating the underlying thrombophilia, timely thrombolysis may be beneficial. Repurposed arterial thrombectomy devices may not perform as expected in the cerebral venous sinus, and there are currently no preclinical endovascular thrombectomy (EVT) models for CVST. Contrary to arterial stroke research, preclinical models utilized to test various endovascular techniques and devices are lacking. The purpose of this research was to develop a reliable preclinical animal model for the testing of endovascular strategies to treat CVST.METHODSFive consecutive male Yorkshire swine weighing 45 kg were utilized. Thrombosis of the superior sagittal sinus was induced with a bovine thrombin injection via a microcatheter under distal balloon occlusion for 15 minutes. Combined arterial injections and superselective sinus injections confirmed the extent of thrombosis. EVT was subsequently performed using a second-generation stent retriever, followed by intravascular optical coherence tomography (OCT) imaging to assess the luminal environment after thrombectomy.RESULTSThrombosis of the superior sagittal sinus, EVT, and subsequent OCT imaging were technically successful in 4 of the 5 swine. Recanalization of the sinus with a second-generation stent retriever was successful after one attempt in 3 of 4 swine (75%), and 1 swine required two attempts. OCT imaging after thrombectomy revealed regions of residual sinus luminal thrombus despite complete angiographic recanalization. Thrombosed bridging cortical veins were also observed before draining into the sinus, along with patent cortical veins.CONCLUSIONSThe authors describe a preclinical model to assess endovascular techniques and devices for the treatment of CVST. Repurposed devices from arterial stroke may not perform as expected, given the unique features of venous sinus thrombosis. Residual bridging cortical vein thrombus and residual sinus thrombus, visualized on intravascular OCT, may be present despite complete sinus recanalization on angiography, and this may be the etiology of the poor clinical outcome despite technical success. In the setting of bridging cortical vein thrombus after successful sinus thrombectomy, direct chemical thrombolysis may be warranted to dissolve the remaining clot. This model may be helpful in developing and testing a new generation of devices designed specifically for CVST treatment.

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Cerebral Venous Thrombosis in Two Patients with Spontaneous Intracranial Hypotension

Case Reports in Neurological Medicine ◽

10.1155/2014/528268 ◽

2014 ◽

Vol 2014 ◽

pp. 1-7 ◽

Cited By ~ 1

Author(s):

M. C. Garcia-Carreira ◽

D. Cánovas Vergé ◽

J. Branera ◽

M. Zauner ◽

J. Estela Herrero ◽

...

Keyword(s):

Venous Thrombosis ◽

Cerebral Venous Thrombosis ◽

Intracranial Hypotension ◽

Superior Sagittal Sinus ◽

Spontaneous Intracranial Hypotension ◽

Cerebrospinal Fluid Leak ◽

Cerebral Veins ◽

Cortical Vein ◽

Sagittal Sinus ◽

Fluid Leak

Although few patients with spontaneous intracranial hypotension develop cerebral venous thrombosis, the association between these two entities seems too common to be simply a coincidental finding. We describe two cases of spontaneous intracranial hypotension associated with cerebral venous thrombosis. In one case, extensive cerebral venous thrombosis involved the superior sagittal sinus and multiple cortical cerebral veins. In the other case, only a right frontoparietal cortical vein was involved. Several mechanisms could contribute to the development of cerebral venous thrombosis in spontaneous intracranial hypotension. When spontaneous intracranial hypotension and cerebral venous thrombosis occur together, it raises difficult practical questions about the treatment of these two conditions. In most reported cases, spontaneous intracranial hypotension was treated conservatively and cerebral venous thrombosis was treated with anticoagulation. However, we advocate aggressive treatment of the underlying cerebrospinal fluid leak.

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Dural Arteriovenous Fistula Associated With Superior Sagittal Sinus Occlusion Secondary to Invasion by a Parafalcine Meningioma

Neurosurgery ◽

10.1227/01.neu.0000370089.94032.4f ◽

2010 ◽

Vol 67 (1) ◽

pp. E205-E207 ◽

Cited By ~ 8

Author(s):

Maria M. Toledo ◽

Thomas J. Wilson ◽

Shervin Dashti ◽

Cameron G. McDougall ◽

Robert F. Spetzler

Keyword(s):

Arteriovenous Fistula ◽

Dural Arteriovenous Fistula ◽

Superior Sagittal Sinus ◽

Sinus Thrombosis ◽

Dural Sinus ◽

External Carotid ◽

Predisposing Factor ◽

Falx Cerebri ◽

Cortical Vein ◽

Sagittal Sinus

Abstract OBJECTIVE We report a rare case of thrombosis of the superior sagittal sinus associated with a parafalcine meningioma resulting in a superior sagittal sinus dural arteriovenous fistula (dAVF). We conclude that dural sinus thrombosis is a significant predisposing factor for development of a dAVF. CLINICAL PRESENTATION A 60-year-old man had a left parietal parafalcine meningioma that invaded the posterior third of his superior sagittal sinus, leading to its occlusion and presumably resulting in an associated dAVF. The fistula was fed by the middle meningeal and superficial temporal arteries on both sides and drained through a superior interhemispheric cortical vein into the vein of Galen and straight sinus. INTERVENTION AND TECHNIQUE The parafalcine mass, which involved the sagittal sinus, was excised via a left parieto-occipital craniotomy. It was decided to resect the dAVF at a later date. Seven days after the original operation, the patient underwent a parietal interhemispheric approach for occlusion of the dAVF. Dissection proceeded until a large arterialized vein and venous pouch with multiple feeders from both external carotid arteries were observed. The vein, which was partially embedded within the falx cerebri, was collapsed, and a second indocyanine green injection confirmed cessation of blood flow. CONCLUSION This report supports that dAVFs are acquired lesions and that venous outflow obstruction is a significant contributing factor to their development. In meningiomas associated with the dural sinuses, diagnostic evaluation for possible dAVFs should be considered. Treatment of these lesions should be based on risk factors because spontaneous resolution after tumor excision has been reported.

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Prophylactic lumboperitoneal shunt in cases of cerebral venous sinus thrombosis with papilledema

International Surgery Journal ◽

10.18203/2349-2902.isj20212715 ◽

2021 ◽

Vol 8 (7) ◽

pp. 2104

Author(s):

Deepak Ranade ◽

Bhagirath More ◽

Dushyant Kashyap ◽

Vybhav Raghu ◽

Shobhit Chhabra

Keyword(s):

Complete Resolution ◽

Superior Sagittal Sinus ◽

Sinus Thrombosis ◽

Cerebral Venous Sinus Thrombosis ◽

Venous Sinus ◽

Shunt Insertion ◽

Venous Sinus Thrombosis ◽

Cortical Vein ◽

Sagittal Sinus ◽

Cortical Vein Thrombosis

Background: Although the mainstay of cerebral venous sinus thrombosis treatment is medical, rarely surgical intervention is warranted. We aimed to determine the role of prophylactic lumbo-peritoneal (LP) shunt in cases of CVST with papilledema.Methods: This is a retrospective review of 70 cases of CVST managed between November 2019 to April 2020. Indications for surgical management included poor response to medical management and severe vision impairment.Results: The mean age of the patients included in the study was 39.44±4.76 years. The most common presenting complaint was headache (83%) and nausea/vomiting (69%). On examination, the common findings were papilledema (57%), blurred vision (31%), double vision (21%) and hemiparesis (11%). Two cases had sudden loss of vision, who underwent emergency LP shunt surgery. Of the 40 cases with papilledema, 8 had severe papilledema. Based on MRI venography, transverse sinus was involved in half of all patients, superior sagittal sinus was involved in 29% and 21% had both the sinuses involved, while 7% had cortical vein thrombosis. Anticoagulants was the first line of therapy for the patients. Papilledema was present in 40 cases, of which 10 showed complete resolution of symptoms, 15 cases had reduced severity of symptoms and symptoms persisted in rest of the 15 cases. The 10 cases who had complete resolution of symptoms included two patients who underwent LP shunt. There were no deaths.Conclusions: We recommend that a LP shunt insertion in a patient with severe papilledema with superior sagittal sinus thrombosis can prevent disease progress, preserve vision and facilitate re-canalisation.

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Experimental and Numerical Modelling of the Ventriculo-Sinus Shunt to Treat Malresoptive Hydrocephalus

ASME 2007 Summer Bioengineering Conference ◽

10.1115/sbc2007-177054 ◽

2007 ◽

Author(s):

Koen Van Canneyt ◽

Jan Kips ◽

Guy Mareels ◽

Edward Baert ◽

Dirk Van Roost ◽

...

Keyword(s):

Intracranial Pressure ◽

Experimental Model ◽

Superior Sagittal Sinus ◽

Ex Vivo ◽

Cortical Vein ◽

Sagittal Sinus ◽

Mri Scans ◽

Hydrocephalus Treatment ◽

Sinus Pressure

This study assesses malresorptive hydrocephalus treatment by ventriculosinus (VS) shunting with the shunt in antegrade or retrograde position. First, an experimental model of the cerebral ventricles, the arachnoid villi, the cortical veins and the superior sagittal sinus (SSS) was built. For this purpose, the compliance of a human cortical vein was measured ex vivo and then modelled by means of Penrose tubes. The dimensions of the superior sagittal sinus were also determined in vivo by measurements on MRI-scans of 21 patients. Secondly, with the experimental model, a numerical model of the cortical veins and the superior sagittal sinus was validated. The experimental and numerical pressure difference between the intracranial pressure and the static sinus pressure was small (0–20 Pa) and corresponded with the theoretically expected values. No overdrainage was found in either antegrade or retrograde position of the shunt. Blood reflow was only found while mimicking lumbar puncture or changes in position with the experimental model (fast lowering the intracranial pressure respectively fast increasing the sinus pressure). Both model results confirm the potential of ventriculosinus shunting as therapy for malresorptive hydrocephalus patients. The ventriculosinus shunt thus proves to be a promising technique.

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On the Mechanical Behavior of the Orthotropic Cord-Rubber Composite

Tire Science and Technology ◽

10.2346/1.2167223 ◽

1976 ◽

Vol 4 (4) ◽

pp. 219-232 ◽

Cited By ~ 2

Author(s):

Ö. Pósfalvi

Keyword(s):

Mechanical Behavior ◽

Uniaxial Tension ◽

Elastic Properties ◽

Large Deformations ◽

Virtual Work ◽

Poisson's Ratio ◽

Principle Of Virtual Work ◽

Effective Elastic Properties ◽

Rubber Composite ◽

Mooney Equation

Abstract The effective elastic properties of the cord-rubber composite are deduced from the principle of virtual work. Such a composite must be compliant in the noncord directions and therefore undergo large deformations. The Rivlin-Mooney equation is used to derive the effective Poisson's ratio and Young's modulus of the composite and as a basis for their measurement in uniaxial tension.

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