Head, neck and vertebral column
David Heylings, Stephen Carmichael, Samuel Leinster, Janak Saada, Bari M. Logan, Ralph T. Hutchings in McMinn’s Concise Human Anatomy, 2017
Venous sinuses - veins within the skull formed by a double layer of dura mater normally located where dural folds meet the bones of the skull (Figs.3.1, 3.3, 3.4). The superior sagittal sinus (in the superior edge of the falx cerebri) runs posteriorly below the midline of the cranial vault to the confluence of sinuses. Most of the blood normally flows to the right, becoming the right transverse sinus, which in turn runs down as the right sigmoid sinus to pass through the jugular foramen on the right and emerging inferior to the skull as the right internal jugular vein. The straight sinus receives the inferior sagittal sinus (lying in the lower edge of the falx cerebri) and the great cerebral vein and runs posteriorly to the confluence of sinuses at the junction of the falx cerebri and tentorium cerebelli. Most of this blood normally flows to the left as the left transverse sinus, which continues as the left sigmoid sinus and, via the left jugular foramen, becomes the left internal jugular vein. The paired cavernous sinuses lie on either side of the pituitary gland and body of the sphenoid bone.
Neurologic disorders in pregnancy
Hung N. Winn, Frank A. Chervenak, Roberto Romero in Clinical Maternal-Fetal Medicine Online, 2021
The risk of CVT is increased both during pregnancy and in the puerperium. Many conditions such at thrombophilias (factor V Leiden and prothrombin gene mutations, deficiencies of protein C or S, or presence of high titers of antiphospholipid antibodies), red blood cell disorders such as sickle-cell anemia or polycythemia, local infections (meningitis, cerebral abscess, sinus or inner ear infections), and dehydration among others can predispose to CVT. When the superior sagittal sinus is involved by thrombosis, the intracranial pressure may be raised producing headaches and papilledema. If the cerebral cortical veins are involved, cerebral hemorrhages, strokes, and seizures may occur. Diagnosis of CVT is made by magnetic resonance imaging (MRI) and MR venography (MRV). Treatment of CVT is anticoagulation with heparin. Warfarin is contraindicated in pregnancy due to the risk of fetal hemorrhage and malformation.
Paper 3
Amanda Rabone, Benedict Thomson, Nicky Dineen, Vincent Helyar, Aidan Shaw in The Final FRCR, 2020
The history and CT findings are suggestive of venous sinus thrombosis. This most commonly affects the superior sagittal sinus, leading to bilateral parasagittal infarcts. Thrombus in the straight sinus or vein of Galen may lead to basal ganglia infarcts. Infarct affecting the temporal lobe could be secondary to a transverse or sigmoid sinus thrombus or thrombus in the vein of Labbe. CT or MR venogram is the next best investigation, depending on availability. MRI will show loss of normal flow venous voids in the area of thrombosis. MRV sequences (either time-of-flight or post gadolinium) will show filling defects in the affected vein. Asymmetrical hypoplastic transverse and sigmoid sinuses can be misleading. Remember to look at the jugular foramen; if it is also small it can help to distinguish between the two.
Postoperative Focal Lower Extremity Supplementary Motor Area Syndrome: Case Report and Review of the Literature
Published in The Neurodiagnostic Journal, 2021
Nicholas B. Dadario, Joanna K. Tabor, Justin Silverstein, Xiaonan R. Sun, Randy S. DAmico
Surgical resection during stage II proceeded without complication. The entirety of the left frontal region as well as a portion of the involved superior sagittal sinus was resected. Again, the lateral and inferior and posterior margins of the tumor were noted to have infiltrated the pia arachnoid of the underlying brain. These regions were carefully resected. The patient awoke with mild language deficits including persistent repetition, paraphasic errors and word finding difficulty which resolved prior to discharge. Post-operative brain MRI demonstrated resection of the bifrontal disease with known residual within the posterior superior sagittal sinus. The diffusion-weighted images demonstrated multiple punctate areas of diffusion abnormality within the high frontal and parietal lobes with corresponding ADC drop-off compatible with mild ischemic changes or devitalized tissue along the regions of brain invasion. Post-operative MRI of the lumbar spine confirmed no spinal pathology capable of producing an isolated foot drop. Post-operative EEG again demonstrated no focal seizure activity although the patient did suffer post-operative epileptiform events involving speech arrest ultimately controlled on anticonvulsants. His left foot began functioning on approximately post-operative day 7 with initial extensor hallucis longus movement progressing to dorsiflexion and plantarflexion abilities prior to discharge on post-operative day 11.
Surgical outcomes and prognostic factors of parasagittal meningioma: a single-center experience 165 consecutive cases
Published in British Journal of Neurosurgery, 2022
Bo Wang, Gui-Jun Zhang, Zhen Wu, Jun-Ting Zhang, Pi-Nan Liu
Reconstruction of the superior sagittal sinus is one of the critical steps in successful operation. Many techniques and materials for repair and vein grafting of the sagittal sinus have been proposed. In our cases, autologous tissue was acceptable as repair material at the preferred source, such as adjacent autologous periosteum, autologous temporalis fascia, and autologous cerebral falx. Additionally, adequate resources were more readily available, lower economic burden, and better histocompatibility compared with artificial materials.11 If a relatively small area wall of the sinus was invaded (type III), repair with a patch of adjacent free autologous periosteum was recommended. If a relatively large area wall of the sinus was invasive (type IV), repair with a patch of reversal cerebral falx was proposed. The latter was more concise and facilitated to a short operation period. Temporary haemostasis of the sinus was easily achieved by temporarily plugging wet cotton strips, temporary vascular clamps, and aneurysm clips were avoided because of their propensity to crush the sinus walls. After the reconstruction of the superior sagittal sinus, verifying the patency of the superior sagittal sinus was an indispensable step. Although indocyanine green video angiography has been used for identification,11 patients are still at risk of delayed cerebral venous infarction during the week following surgery. Intermediate MRI examination of patients was helpful in the timely discovery of infarct.
Clinical features of patients with high and normal CSFP in venous pulsating tinnitus
Published in Acta Oto-Laryngologica, 2020
The flow of cerebrospinal fluid has a certain directionality. The collateral plexus of the two lateral ventricles is the most abundant and produces most of the cerebrospinal fluid. This cerebrospinal fluid flows into the third ventricle through the interventricular pores and then flows into the fourth ventricle through the midbrain aqueduct. The cerebrospinal fluid produced by the choroid plexus of each ventricle converges in the fourth ventricle and flows into the subarachnoid space of the brain and spinal cord through the median and lateral foramina of the fourth ventricle. Finally, the cerebrospinal fluid infiltrates into the superior sagittal sinus through the arachnoid granules beside the sagittal sinus before returning to the venous system [16–18]. Under normal circumstances, there are arachnoid granules in the cross-sectional area of the transverse sinus and sigmoid sinus on the dominant drainage side. When inflammation occurs, it may cause adhesion and narrowing of the vascular lumen, and hemodynamic changes occur when blood flows through the stenosis. Watane et al also found a correlation between arachnoid granules and BIH [19]. Most MRA and MRV results in this study showed superior drainage of the sigmoid sinus on the tinnitus side. We speculate that high CSFP may impact the hemodynamics of intracranial veins, and abnormal intracranial veins may also affect CSFP; that is to say, intracranial veins and CSFP interact through the important medium – arachnoid granules, and thereby participate in the occurrence and development of vascular tinnitus.
Related Knowledge Centers
- Arachnoid Granulation
- Cerebrospinal Fluid
- Confluence of Sinuses
- Emissary Veins
- Falx Cerebri
- Parietal Lobe
- Occipital Lobe
- Frontal Lobe
- Head
- Confluence of Sinuses
- Foramen Cecum