The syndrome of latent cerebral venous thrombosis: its frequency and relation to age and congestive heart failure

Cerebral Venous Sinus Thrombosis

Cerebral venous sinus thrombosis (CVST) is a rare type of stroke indicated by the formation of blood clots within the dural venous sinuses. These are large venous conduits that are situated between the 2 layers of the dura mater which are responsible for draining blood from the brain and returning it to the systemic circulation. Cortical venous thrombosis refers to the blockage of veins on the brain's cortical surface. Cerebral venous thrombosis encompasses both dural and cortical vein occlusions.

A case of cerebral venous sinus thrombosis presented with SAH and isolated headache

Cerebral venous sinus thrombosis is a rare and challenging type of stroke. Coexistence of subarachnoid hemorrhage adds complexity to the diagnostic process leading to a missed or delayed diagnosis. Isolated headaches can be the only presentation and urgent neuroimaging using CT or MR venogram plays a pivotal role in the workup of these cases. We report a rare case of 64-years-old patient with subarachnoid hemorrhage and underlying cerebral venous sinus thrombosis who was presented with isolated headache where the management is different from arterial subarachnoid hemorrhage.

Missed Cerebral Venous Thrombosis: A Diagnostic Challenge

Rates of cerebral venous sinus thrombosis (CVT) misdiagnosis or at times delayed diagnosis and related outcomes have remained underexplore, and also there is less knowledge about the long-term outcome of patients with untreated cerebral venous sinus thrombosis (CVT). Long-term presentations of untreated CVT are rare. We hereby presenting series of four interesting patients of chronic CVT whose diagnosis was missed and how varied chronic presentations of untreated CVT appeared to neurology and how subtle radiologic features helped with correct diagnosis.

Unilateral Abducens Nerve Palsy as the Lone Sign of Cerebral Venous Sinus Thrombosis: A Case Report and Literature Review

Cerebral venous thrombosis (CVT) is a rare condition characterized by the obstruction of cerebral venous sinuses or cortical veins, leading to stroke-like symptoms. This case report presents a case of a 74-year-old male with isolated unilateral abducens nerve palsy as the sole sign of CVT, without accompanying symptoms or focal deficits. Neuroimaging, including CT and magnetic resonance venography, confirmed the diagnosis of CVT with a thrombus in the right transverse sinus. The patient was co-managed with the medical team and initiated on anticoagulation therapy. Follow-up showed resolution of diplopia and improvement in extraocular muscle movements. Unilateral abducens nerve palsy in CVT is rare, with most cases presenting as bilateral palsy. The case report emphasizes the importance of considering CVT in the differential diagnosis of isolated abducens nerve palsy and highlights the role of neuroimaging in early detection. Timely diagnosis and appropriate management are crucial for favorable outcomes in CVT cases. Further research is needed to enhance understanding of the pathophysiology, prognosis, and optimal management of this uncommon presentation.

What about cerebral venous sinus thrombosis? A series of three autopsy cases

Cerebral venous sinus thrombosis (CVST) is an uncommon cerebrovascular disorder that gained massive media attention in 2021, when an association between COVID-19 and its vaccines was found in several reported cases, raising the suspicion of a causative relation that is still debated.

Three cases of CVST unrelated to COVID-19 are reported in this article to highlight the difficulty in the early recognition and management of this condition, as it occurs in a variety of diseases with different clinical and pathological manifestations.

When the diagnosis cannot be achieved in the clinical setting, the role of the pathologist becomes essential in the determination of the cause of death and in the identification of the etiology of CVST.

During the autopsy, coordination between the physician and the forensic pathologist is crucial to correlate the clinical presentation with the pathological picture.

Cerebral venous thrombosis: a practical guide

All neurologists need to be able to recognise and treat cerebral venous thrombosis (CVT). It is difficult to diagnose, partly due to its relative rarity, its multiple and various clinical manifestations (different from 'conventional' stroke, and often mimicking other acute neurological conditions), and because it is often challenging to obtain and interpret optimal and timely brain imaging. Although CVT can result in death or permanent disability, it generally has a favourable prognosis if diagnosed and treated early. Neurologists involved in stroke care therefore also need to be aware of the treatments for CVT (with varying degrees of supporting evidence): the mainstay is prompt anticoagulation but patients who deteriorate despite treatment can be considered for endovascular procedures (endovascular thrombolysis or thrombectomy) or neurosurgery (decompressive craniotomy). This review summarises current knowledge on the risk factors, diagnosis, treatment and prognosis of CVT in adults, and highlights some areas for future research.

Etiologic and Clinical Features of Cerebral Venous Sinus Thrombosis in Saudi Arabia

Objective:

Our study aims to evaluate the etiologic and clinical features of cerebral venous sinus thrombosis (CVST) in Saudi Arabia, and secondarily whether gender plays a role in CVST.

Materials and Methods:

Data were collected retrospectively from the stroke registry during the period from January 2008 to April 2018, and the patients with the diagnosis of CVST were identified, and data were analyzed for any gender-specific differences in clinical presentation and etiology of cerebral venous thrombosis.

Results:

There were 15 females while 11 males with a female:male ratio of 1.4:1. The mean age was 29.4± standard deviation 8.9 with the age range of 15–49. Headache was the most common and usually the first presenting symptoms present in 65% followed by hemiparesis and cranial nerve palsies. The first neurological examination was normal in 9/26 (34.6%) of the patients, while the common abnormality was cranial nerve palsies. Infections and trauma played an important part in risk factor analysis of our patient after the pregnancy- and hormone-related conditions. Some significant differences between the clinical presentation and risk factors among males and females were noted as age at presentation was higher in females while trauma and infections were common in male patients, although the involvement of the sinuses and response to treatment did not prove to be statistically significant.

Conclusion:

The results of this study were similar to the available literature with few differences. The relatively higher proportion of males in our study can be explained partly with more cases of traumatic CVST. Some important differences were noted between the risk factors and clinical presentation among genders. Large-scale prospective studies are needed to further clarify these differences.

High resolution atlas of the venous brain vasculature from 7 T quantitative susceptibility maps

The vascular organization of the human brain can determine neurological and neurophysiological functions, yet thus far it has not been comprehensively mapped. Aging and diseases such as dementia are known to be associated with changes to the vasculature and normative data could help detect these vascular changes in neuroimaging studies. Furthermore, given the well-known impact of venous vessels on the blood oxygen level dependent (BOLD) signal, information about the common location of veins could help detect biases in existing datasets. In this work, a quantitative atlas of the venous vasculature using quantitative susceptibility maps (QSM) acquired with a 0.6-mm isotropic resolution is presented. The Venous Neuroanatomy (VENAT) atlas was created from 5 repeated 7 Tesla MRI measurements in young and healthy volunteers (n = 20, 10 females, mean age = 25.1 ± 2.5 years) using a two-step registration method on 3D segmentations of the venous vasculature. This cerebral vein atlas includes the average vessel location, diameter (mean: 0.84 ± 0.33 mm) and curvature (0.11 ± 0.05 mm^-1) from all participants and provides an in vivo measure of the angio-architectonic organization of the human brain and its variability. This atlas can be used as a basis to understand changes in the vasculature during aging and neurodegeneration, as well as vascular and physiological effects in neuroimaging.

Cerebral Venous Sinus Thrombosis: Prognostic and Therapeutic Significance of an Early Radiologic Diagnosis

We describe the CT and MRI patterns of cerebral venous sinus thrombosis (CVST) on the basis of the venous angioarchitecture and the underlying pathophysiological mechanism. We also investigated if any radiologic data exist to establish which patients can be followed conservatively and which warrant endovascular treatment.

The clinical, CT-CTA and MRI-MRA findings of 11 patients (2 men; 9 women; 24 to 69 years-old) with CVST were reviewed. The morphological patterns of CVST were divided into two major groups: Vascular signs: spontaneous sinusal hyperdensity (9); spontaneous all-sequences hyperintensity (4); venous engorgement (9); empty delta sign (4); lack of sinusal contrast-enhancement (3); delayed sinusal transit-time (11); lack of flow-related signal (3). Parenchymal signs: mass effect and cortical sulcal effacement (8), white matter edema (7), venous ischemia (6), haemorrhagic infarct (3), breakdown of the blood-brain barrier (4), hydrocephalus (2).

The clinical and radiologic pictures are related to cerebral venous angioarchitecture and underlying pathophysiologic mechanism of venous thrombosis. Reversibility of clinical symptoms and parenchymal lesions is far more frequent, because vessel damage slowly and progressively develops, whereas damage to brain tissue occurs later. Consequently, a prompt CT-MRI diagnosis may allow a good prognosis. Treatment using selective sinusal instillation of urokinase is considered only when the patient clinically and radiologically does not improve within the first two weeks after heparinization.

Diagnostic Performance of Routine Brain MRI Sequences for Dural Venous Sinus Thrombosis

BACKGROUND AND PURPOSE

Signs suggestive of unexpected dural venous sinus thrombosis are detectable on routine MR imaging studies without MRV. We assessed performance characteristics and interrater reliability of routine MR imaging for the diagnosis of dural venous sinus thrombosis, focusing on the superior sagittal, transverse, and sigmoid sinuses.

MATERIALS AND METHODS

This case series included 350 patients with MRIs performed with contrast-enhanced MRV and 79 patients with routine MRIs performed within 48 hours of a CTV from 2008 to 2014 (total, n = 429). Routine MR images were separated from the contrast-enhanced MRVs and CTVs. Three neuroradiologists, blinded to clinical data, independently reviewed the MRIs for signs of dural venous sinus thrombosis, including high signal on sagittal T1, loss of flow void on axial T2, high signal on FLAIR, high signal on DWI, increased susceptibility effects on T2*-weighted gradient recalled-echo imaging, and filling defects on axial contrast-enhanced spin-echo T1WI and/or volumetric gradient-echo T1WI. Two neuroradiologists independently reviewed contrast-enhanced MRVs and CTVs to determine the consensus gold standard. Interrater reliability was calculated by using the κ coefficient.

RESULTS

Contrast-enhanced MRV and CTV confirmed that dural venous sinus thrombosis was present in 72 of 429 cases (16.8%). The combination of routine MR sequences had an overall sensitivity of 79.2%, specificity of 89.9%, and moderate interrater reliability (κ = 0.50). The 3 readers did not have similar performance characteristics. 69.4% of positive cases had clinical suspicion of dural venous sinus thrombosis indicated on imaging requisition.

CONCLUSIONS

Routine MR images can suggest dural venous sinus thrombosis with high specificity in high-risk patients, even in cases without clinical suspicion.

Direct thrombolysis for cerebral venous sinus thrombosis

Cerebral venous sinus thrombosis (CVST) is an increasingly diagnosed disease with a wide range of symptoms, ranging from a mild headache to cerebral herniation. A potentially devastating syndrome, CVST has been associated with a mortality rate of 6-10%. In prospective studies, the overall rate of death and dependency from CVST ranges from 8.8 to 44.4%. Systemic anticoagulation remains the first-line treatment. However, a percentage of patients deteriorate despite medical therapy. These cases have resulted in the development of thrombolysis or endovascular treatment for CVST. Initial reports of the use of endovascular treatment of CVST have been promising. However, enthusiasm for the use of endovascular thrombolysis and thrombectomy should be tempered by an understanding of possible risks such as intracerebral hemorrhage and/or vessel dissection. The authors review the literature regarding endovascular treatment of CVST with a description of the chemical and mechanical thrombolytic techniques.

High spatial resolution magnetic resonance imaging of experimental cerebral venous thrombosis with a blood pool contrast agent

PURPOSE

The purpose of this study was to investigate the feasibility of clot visualization in small sinus and cortical veins with contrast enhanced MRA in a cerebral venous thrombosis animal model using a blood pool contrast agent, Gadofosveset, and high spatial resolution imaging.

MATERIAL AND METHODS

For induction of cerebral venous thrombosis a recently developed combined interventional and microsurgical model was used. Cerebral sinus and cortical vein thrombosis was induced in six pigs. Two further pigs died during the procedure. Standard structural, time-of-flight- and phase contrast-angiograms were followed by fast time resolved high resolution 3D MRA (4D MRA) and subsequent high spatial resolution 3D MRA in the equilibrium phase with and without addition of parallel imaging. Visualization of the clots using the different sequences was subjectively compared and contrast-to-noise ratio (CNR) was assessed.

RESULTS

In the remaining six animals the procedure and MR-imaging protocol including administration of Gadofosveset was successfully completed. The 3D high resolution MRA in the equilibrium phase without the addition of parallel imaging was superior to all the other applied MR measurement techniques in terms of visualization of the clots. Only applying this sequence bridging vein thromboses were also seen as a small filling defect with a high CNR of >18.

CONCLUSION

Only the non-accelerated high spatial resolution 3D MRA in the equilibrium in conjunction with the blood pool agent Gadofosveset allows for high-contrast visualization of very small clots in the cerebral sinus and cortical veins. STATEMENT CLINICAL IMPACT: Detection of cortical vein thrombosis is of high clinical impact. Conventional MRI sequences often fail to visualize the clot. We could demonstrate that, in contrast to conventional sequences, with high spatial resolution 3D MRA in the equilibrium in conjunction with the blood pool agent Gadofosveset very small clots in the cerebral sinus and cortical veins could be successfully visualized. We think that with the presented approach cortical vein thrombosis might also be sufficiently visualized in patients.

New experimental model of sinus and cortical vein thrombosis in pigs for MR imaging studies

INTRODUCTION

Diagnosis of cerebral sinus vein thrombosis is still a challenge for imaging. MRI and MRA play a major role in sinus imaging. For further development of MR techniques, MR-compatible animal models are required. The aim of this study was to develop an animal model for sinus thrombosis and additional cortical vein thrombosis with a clot of human blood for MR imaging studies.

METHODS

A combined surgical and interventional approach was carried out in 13 pigs. After minimal invasive surgical access to the anterior superior sagittal sinus and cortical vein, thrombosis with human blood was induced using an interventional catheter approach. MR imaging was performed prior to and after thrombus induction.

RESULTS

Sinus thrombosis was induced in 12 of 13 animals. Three animals suffered acute subdural haemorrhage; one of these animals died during the intervention, and one died after thrombus induction. MR imaging of the thrombosed sinus could easily be performed without significant artefacts in 11 of 13 animals.

CONCLUSION

This new model of sinus and cortical vein thrombosis with a clot of human blood allows artefact-free imaging studies on MR.

Cerebral venous thrombosis: a review

BACKGROUND

Cerebral venous thrombosis (CVT) is less frequent than arterial thrombosis, presents in an atypical fashion, and is an uncommon cause of stroke. Although the functional outcome from CVT is better than arterial strokes, the outcome of CVT remains unpredictable and may lead to sequelae or even death if not recognized and treated early.

REVIEW SUMMARY

The clinical presentations, time of onset, and neuroimaging findings vary. Symptoms include headache, seizures, neurologic deficits, and altered consciousness. Causes include hematologic disorders, hypercoagulable states, pregnancy, and contraceptive medications. Treatment of this infrequent condition remains controversial and includes heparin infusions, intrasinus thrombolysis, and other endovascular procedures.

CONCLUSION

Further clinical trials are needed to address optimal treatment of this infrequent but potentially serious condition.

Estudio no invasivo de las venas cerebrales y los senos durales: comparación de dos técnicas de angiografía con resonancia magnética

OBJECTIVE

To evaluate MR venography with bolus injection of intravenous contrast and elliptical filling of the K space, using three-dimensional fast spoiled gradient-echo (3D-FSPGR) sequences, and to compare it to the technique most frequently employed in the study of cerebral veins and dural sinuses, which is two-dimensional time-of-flight (2D-TOF) MR venography.

MATERIAL AND METHODS

Source images, multiplanar reconstructions, and maximum intensity projections (MIP) were obtained using both 2D-TOF venography and contrasted-enhanced 3D-FSPGR venography in 20 healthy volunteers. Two radiologists independently evaluated both techniques for the visualization of twenty-one predefined venous structures, classifying the depiction as completely visible, partially visible, or not visible.

RESULTS

The predefined venous structures were completely visible in 795 of 840 (94.6%) of the evaluations of contrast-enhanced 3D-FSPGR images versus 682 of 840 (81.1%) evaluations of 2D-TOF venography images. In the major dural sinuses, visualization was complete in 99.4% of the readings of contrast-enhanced 3D-FSPGR images versus 81% in the readings of the 2D-TOF images.

CONCLUSION

3D-FSPGR with elliptical filling of the K space and bolus injection of contrast material provides higher quality images of the intracranial venous system than those obtained using 2D-TOF sequences.

More reliable noninvasive visualization of the cerebral veins and dural sinuses: comparison of three MR angiographic techniques

PURPOSE

To compare the visualization of cerebral veins and dural sinuses at contrast material-enhanced three-dimensional (3D) fast low-angle shot (FLASH) magnetic resonance (MR) angiography, time-of-flight (TOF) MR angiography, and phase-contrast MR angiography.

MATERIALS AND METHODS

The authors prospectively compared the two-dimensional source images, multiplanar reconstructed images, and maximum intensity projection angiograms obtained at contrast-enhanced 3D radio-frequency-spoiled FLASH MR angiography in 20 patients with those obtained at TOF and phase-contrast MR angiographic examinations. Two neuroradiologists in consensus determined the number of visualized cortical veins and graded the quality of visualization of veins and sinuses as intense and continuous, faint and continuous, or noncontinuous. Statistical analysis was performed with the nonparametric sign test and the Wilcoxon matched pairs sign rank test.

RESULTS

The cortical veins, inferior sagittal sinus, and cavernous sinuses were visualized best with FLASH MR angiography (P <.003). The Trolard and Labbé veins were visualized equally well with the FLASH and TOF sequences. For septal, internal cerebral, and Rosenthal left basal vein visualization, phase-contrast MR angiography was inferior to the FLASH and TOF MR angiographic examinations (P <.05). The quality of visualization of the thalamostriate and Galen veins and of the superior sagittal, rectal, and transverse sinuses was the same at all MR angiographic examinations.

CONCLUSION

Three-dimensional FLASH MR angiography depicts some venous structures better than do TOF and phase-contrast MR angiographic examinations. The depiction of other veins is the same with 3D FLASH and TOF sequences.

Acute Treatment of Cerebral Venous Thrombosis

Correct and timely diagnosis of cerebral venous thrombosis (CVT) is imperative in determining the appropriate treatment plan. Clinical suspicion is crucial, followed by radiographic confirmation using CT, MRI, or conventional angiography. Emergency and critical care of the patient is important, including control of airway and circulation. Initially, the treatment of choice is anticoagulation with heparin. Consideration should be given to intrathrombus delivery of thrombolytic agents. Eventually, newer techniques such as laser, ultrasound, and suction may be considered.

Cerebral venous thrombosis in young adults: 2 Case reports

Cerebral venous thrombosis (CVT) is a disease with multiple known etiologies that present with a remarkably wide spectrum of clinical signs and symptoms. We present a case of a 34-year-old man with a history of meningeal symptoms for 1 week after receiving a lumbar injection for lower back pain. He subsequently developed dense right hemiplegia and global aphasia. Head magnetic resonance imaging revealed superior sagittal sinus thrombosis. The patient was started on intravenous heparin but deteriorated neurologically. Urokinase infusion directly into the superior sagittal sinus was performed, with striking functional and neurologic improvement. Lupus anticoagulant was positive. We also present the case of a 24-year-old pregnant woman who developed an acute onset of meningeal symptoms and resultant left hemiparesis. Head magnetic resonance angiography revealed thrombosis of right transverse and sigmoid sinuses. Protein S deficiency was found. She was started on intravenous heparin, then enoxaparin, with improvement in symptoms. These cases demonstrate that CVT can be a cause of stroke in young patients with hypercoagability disorders, and a heightened awareness of CVT will promote optimal medical care and functional outcomes. Excellent functional recovery is likely with early recognition and treatment of the underlying etiology, as well as successful lysis of the clot.

Dural sinus thrombosis endovascular therapy

Dural sinus thrombosis is a relatively rare, but potentially devastating disease. The problem occurs when there is extensive thrombosis of the intracranial dural sinuses, the outflow channels of venous blood from the brain. If recanalization does not occur, venous hypertension can lead to cerebral edema, infarction, and hemorrhage. Treatment of this disease usually involves anticoagulants, but with mixed results. Endovascular approaches using direct infusion of thrombolytic drugs into the occluded sinuses may result in excellent recanalization and improved patient outcomes.

Superior sagittal sinus thrombosis treated with combined local thrombolytic and systemic anticoagulation therapy

We recently encountered a patient with thrombosis of the superior sagittal sinus of an idiopathic cause. The patient was treated initially with combined local thrombolytic therapy through the burr hole over the superior sagittal sinus and systemic anticoagulant therapy. Continuous ventricular drainage and hyperbaric oxygenation therapy were used to control the increased intracranial pressure. The superior sagittal sinus was successfully recanalized. Whereas the patient suffered a complication with subacute subdural haematoma, he was successfully treated with the combination of these therapies. The rationale and approach are discussed.

Cerebral venous thrombosis in young adults. Experience in a stroke unit, 1988-1994

We report a series of nine patients younger than 45 years with angiographically-documented cerebral venous thrombosis, consecutively referred to our Stroke Unit from 1988 to 1994. Two of them were men and seven were women. Eight patients initially complained of headache, often associated with other symptoms of increased intracranial pressure. Seven patients had focal motor deficits and four suffered from epileptic seizures. None of the patients died. Only one patient remained severely disabled, whereas the others recovered self-sufficiency within two months. The use of oral contraceptives was closely associated with the occurrence of venous thrombosis in the women. Cerebral venous thrombosis is to be kept in mind in the differential diagnosis of stroke in the young.

Transcranial color-coded real-time sonography of intracranial veins. Normal values of blood flow velocities and findings in superior sagittal sinus thrombosis

Sonographic findings in patients with superior sagittal sinus thrombosis were compared to those in healthy adults. Two patients with angiographically verified superior sagittal sinus thrombosis were examined by transcranial color-coded real-time sonography (TCCS) after intravenous application of a pulmonary stable ultrasound contrast agent. For comparison, 10 patients without venous pathology had contrast-enhanced TCCS; in addition, 30 healthy adults had plain TCCS to determine the identification rate for deep and superficial venous segments and to define normal values of venous blood flow velocities. The straight sinus was identified in 22 of 30 healthy subjects by plain TCCS, and in 9 of 10 patients by contrast-enhanced TCCS. The mean peak and angle-corrected blood flow velocity was 19.1 +/- 7.1 cm/sec. The superior and inferior sagittal sinuses were identified by contrast-enhanced TCCS in 2 and 1 subjects, respectively; they were never seen on plain TCCS. In the 2 patients with sagittal sinus thrombosis a distinct increase of blood flow velocity was recorded from the straight sinus (83 and 92 cm/sec), most likely reflecting collateral circulation. These preliminary data indicate that TCCS and particularly contrast-enhanced TCCS permit identification and blood flow measurements within the deep and occasionally, the superficial venous system. TCCS may contribute to an assessment of hemodynamic repercussions of venous thrombosis and may indicate the risk of venous infarction and hemorrhage.

Contrast-enhanced MR imaging of dural sinus thrombosis: demonstration of the thrombosis and collateral venous channels

In order to study the role of Gd-DTPA-enhanced MR imaging in dural sinus thrombosis, precontrast and postcontrast imaging using Gd-DTPA in three patients with clinically unsuspected dural sinus thrombosis was reviewed. Comparisons were made with cranial CT scanning and cerebral angiography. Compared to CT, the postcontrast T1-weighted images more clearly revealed thrombus in the dural sinuses as a nonenhanced central area of intermediate intensity (but not flow void) surrounded by an enhanced rim. MR imaging also demonstrated secondary changes, including the presence of collateral venous channels and venous infarction.

Incidence of the empty delta sign in computed tomography in the paediatric age group

The computed tomographic (CT) appearances of dural sinus thrombosis are variable, but include visualization of thrombus within the sinus on post-contrast images (the 'empty triangle' or 'empty delta' sign). This review of 104 consecutive examinations was undertaken to assess the incidence of the empty delta sign in a paediatric group undergoing CT examinations. The number of examinations in which a sagittal sinus filling defect was seen in three or more images, was unexpectedly high. An overall incidence of 18% was noted. Defects due to bone artifact and defects seen on only one or two slices were excluded. The age distribution of abnormal scans was markedly skewed towards young infants. Nine of 27 examinations (33%) in infants less than 1 month of age, were positive for filling defects, compared with six of 21 (29%) aged between 1 and 12 months, and four of 56 (7%) aged over 1 year. This review suggests that the finding of a filling defect or empty delta sign in the sagittal sinus is not pathognomonic for sinus thrombosis that results in clinically apparent manifestations. Second, a filling defect apparent on CT may resolve spontaneously. The incidence of non-occlusive sinus thrombosis may be significantly higher than previously recognized, particularly in young infants where predisposing conditions including dehydration, infection or prematurity coexist. Previous studies have indicated that the sensitivity of the empty delta sign is approximately 30%. This study implies that either the empty sign has limited specificity in the paediatric population, or that unrecognized non-occlusive sinus thrombosis is much more frequent than previously described.

Case report: cerebral venous thrombosis as a manifestation of acute ulcerative colitis

Ulcerative colitis is associated with a number of extraintestinal complications, including the infrequent occurrence of thromboembolic disease. Cerebral venous thrombosis is extremely rare, with only 15 cases reported in the literature. The outcome in this group of patients is poor; the result in more than 80% of the cases is permanent neurologic sequelae or death. The precise mechanisms involved in thrombogenesis remain unclear. A hypercoagulable state may occur in ulcerative colitis because of well-documented associations of thrombocytosis, elevated factors V and VIII and fibrinogen, and decreased antithrombin III. Treatment regimens for cerebral venous thrombosis remain controversial and include anticoagulation with heparin, surgical thrombectomy, and systemic and local infusion of fibrinolytic regimens. A conservative approach with antiedemic agents, anticonvulsants, antiplatelet therapy, and acetazolamide also may be beneficial and offers a substantially reduced hemorrhagic potential. A case of primary superior sagittal sinus thrombosis associated with active ulcerative colitis treated by the latter method is reported. The patient's neurologic recovery was complete, with recanalization of the thrombosed venous sinus being demonstrated by magnetic resonance imaging studies.

Superior sagittal sinus thrombosis and pulmonary embolism: a syndrome rediscovered

Pulmonary emboli as a fatal complication of superior sagittal sinus thrombosis was once well recognized in the literature but appears to have been forgotten. The sagittal sinus appeared to be the source of pulmonary emboli in previously reported cases. Even in patients with no evidence of systemic thrombosis, but who have sagittal sinus thrombosis, the possibility of dislodging pulmonary emboli should be strongly considered. We report a case of nontraumatic sagittal sinus thrombosis complicated by multiple pulmonary emboli and a fatal saddle embolism, likely originating from the thrombosed sinus. Our review of the literature between 1942 and 1990 yielded 203 cases of intracranial venous thrombosis. The overall mortality rate was 49.3%. In 23 cases (11.3%), the venous sinus thrombosis was associated with pulmonary emboli and in these the overall mortality rate was 95.6%. In the 203 cases in our review, those patients who received anticoagulation therapy also had a statistically significant better outcome. Therefore, the presence of pulmonary emboli in association with sagittal sinus thrombosis mandates a sober assessment of the need of anticoagulation therapy in the absence of obvious contraindication.

MRI assessment of unsuspected dural sinus thrombosis

In three patients with clinically unsuspected diagnosis, MRI has afforded a positive and conspicuous demonstration of dural sinus thrombosis, allowing specific treatment and followed by improvement in the patients' condition. Even in retrospect, CT examinations were nondiagnostic. Presenting symptoms were usual and nonspecific. CT and radionuclide scanning have proved valuable when performed on a clinically oriented basis. Angiography cannot be carried out without clear indications. MRI offers advantages in being a non-invasive technique without ionising radiation, allowing direct visualization and accurate delineation of the thrombus. MRI is definitely the method of choice to assess clinically suspected cerebral venous occlusion. As MRI diagnosis relies on a routine examination protocol, we believe that it will detect other unsuspected cases of dural sinus thrombosis.

Superior sagittal sinus thrombosis with intracerebral hematoma

Intracranial hematoma secondary to superior sagittal sinus thrombosis is a well described, but rare event. We present a case of interval resolution of a intracerebral hematoma in a patient with thrombosis of the sagittal sinus.

Diagnosis of superior sagittal sinus thrombosis by computerized tomography. Report of two cases

Superior sagittal sinus thrombosis was diagnosed on computerized tomography (CT) scanning and was subsequently confirmed by angiography in two patients. Small ventricles and filling defects occurring within the sinus (the empty triangle sign) appeared to be highly suggestive of superior sagittal sinus thrombosis, and the association was confirmed angiographically. Potential pitfalls in the CT diagnosis of local obstruction of cerebral venous outflow are described and correlated with the natural history of the disease. The need for improved awareness of the CT appearance of occlusive disease of the dural venous sinuses is stressed.

Dural sinus and cerebral venous thrombosis

Eighty patients with 'primary' dural sinus and cerebral venous thrombosis were seen over a period of 16 years. There was an equal distribution amongst the sexes and the largest number of patients presented in the third decade. The commonest predisposing factors were puerperium, pregnancy, synthetic steroid contraceptives and anaemia. Seventy patients presented in an acute fashion with headache, focal or generalized seizures and focal neurological deficits. Ten patients presented in a subacute to chronic manner, with features to suggest an intracerebral space-occupying lesion. The investigation of choice was angiography. Thirty-five patients were treated conservatively with anticonvulsants, low molecular weight dextran and anti-oedema measures. Anti-coagulants were not used for fear of haemorrhage in the associated red infarcts. Antibiotics were not needed as infection played no part in the pathogenesis. Thirty-four patients needed an operation which took the form of a decompressive craniotomy and dural closure with the aid of a pericranial graft. The conservatively treated group appeared to fare better only because it included patients with a milder ictus. Forty patients improved, three remained unchanged and 37 expired. Autopsy in the 35 of the 37 patients showed cortical vein and sinus thrombosis and oedema with a haemorrhagic infarct. Long term follow-up showed good recovery of neurological function, but epilepsy was a troublesome sequel and needs regular anti-epileptic drug treatment.

The complementary role of angiography and CT in the diagnosis of cerebral sinovenous occlusion

Three patients with angiographic and CT findings of cerebral sinovenous occlusion are described. Filling defects within the venous pathways are well demonstrated by angiography. Some of the most characteristic CR signs are here described. Full evaluation, including the clinical history, angiography and computed tomography is essential.

Superior sagittal sinus thrombosis followed by subdural hematoma

A case of superior sagittal sinus thrombosis followed by a subdrual hematoma is reported. A 33-year-old woman, who presented with serious neurological deficits, made a remarkable recovery with mild residual. She had a thin subdural fluid collection, which eventually developed into a subdural hematoma. After evacuation of the hematoma, she had no neurological deficits. Treatment of cerebral venous and dural sinus thrombosis is discussed.

Cerebral venous thrombosis in the rhesus monkey

Cerebral venous thrombosis was identified in four rhesus monkeys. Two initially showed neurologic signs and three had diarrhea or dysentery. All four had severe intestinal disease, including three cases of ulcerative colitis complicated by extracerebral thromboembolic disease. Central nervous system lesions, confined to the centrum semiovale, were multiple thrombi of internal cerebral veins, perivenular demyelination, and gemistocytic astrocytosis. The lesions resembled those found in people with cerebral venous thrombosis, and support the hypothesis that perivenular demyelination may occur as a sequela to venous occlusion. The lesions were identical to those found in "leukoencephalosis and perivascular myelosis," an entity of unknown cause previously described in monkeys.

Primary cerebral venous thrombosis in young adults: the diverse manifestations of an underrecognized disease

Primary cerebral venous thrombosis has a wide clinical and pathological spectrum, which has not been recognized. Seven cases of aseptic cerebral venous thrombosis (5 fatal) are discussed, with pathological study and literature review. Five patients ranged in age from 22 to 31 years. In 3 cases no discernible cause for thrombosis was found. Novel features of these cases include: primary bilateral internal cerebral venous thrombosis; isolated thrombocytopenia; occurrence in the context of (1) ulcerative colitis plus oral contraceptive use, (2) a twin transfusion syndrome, and (3) presenting syndrome five years after mastectomy for carcinoma. Diagnosis and treatment are discussed, and it is suggested that a focal coagulopathy may be responsible for this underdiagnosed condition.

Acute cerebrovascular and myocardial ischemia superimposed upon chronically hypertensive and arteriosclerotic male Sprague-Dawley rats

Repeatedly bred male rats which develop arteriosclerosis spontaneously were subjected to unilateral nephrectomy, 1% saline drinking water, and 2 mg subcutaneous injections of deoxycorticosterone acetate per animal weekly for 7 weeks to induce severe hypertension (+/- 175 mmHg systolic). Acute cerebral ischemia was induced by ligating one carotid artery. Two days later, experimental animals were subjected to acute myocardial ischemia by injecting them subcutaneously with a single dose of isoproterenol (25 mg/100 g body weight). All of the experimental animals died within 4 hours of the injection of isoproterenol. During this same period, blood pressure, body weight, thymus, kidney, and testicular weights were reduced, whereas heart and adrenal gland weights increased markedly. Serum enzymes (CPK, SGOT, and LDH), lipids (triglycerides and free fatty acids), glucose, BUN, and corticosterone rose progressively. Fatty infiltration of the liver, adrenal hyperplasia, myocardial thrombi, renal degenerative changes, and cerebral edema became progressively more severe. A hypothalamic-pituitary-adrenal axis component may be involved in the reaction to the stress of acute cerebral or myocardial ischemia, which is intensified when the two ischemias are combined, and chronic hypertension may exacerbate both.