Background—The purpose of this statement is to provide an overview of cerebral venous sinus thrombosis and to provide recommendations for its diagnosis, management, and treatment. The intended audi...

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Diagnosis and Management of Cerebral Venous Thrombosis A Statement for Healthcare Professionals From the American Heart Association/American Stroke Association

The incidence of subarachnoid haemorrhage (SAH) is stable, at around six cases per 100 000 patient years. Any apparent decrease is attributable to a higher rate of CT scanning, by which other haemorrhagic conditions are excluded. Most patients are <60 years of age. Risk factors are the same as for stroke in general; genetic factors operate in only a minority. Case fatality is approximately 50% overall (including pre-hospital deaths) and one-third of survivors remain dependent. Sudden, explosive headache is a cardinal but non-specific feature in the diagnosis of SAH: in general practice, the cause is innocuous in nine out of 10 patients in whom this is the only symptom. CT scanning is mandatory in all, to be followed by (delayed) lumbar puncture if CT is negative. The cause of SAH is a ruptured aneurysm in 85% of cases, non-aneurysmal perimesencephalic haemorrhage (with excellent prognosis) in 10%, and a variety of rare conditions in 5%. Catheter angiography for detecting aneurysms is gradually being replaced by CT angiography. A poor clinical condition on admission may be caused by a remediable complication of the initial bleed or a recurrent haemorrhage in the form of intracranial haematoma, acute hydrocephalus or global brain ischaemia. Occlusion of the aneurysm effectively prevents rebleeding, but there is a dearth of controlled trials assessing the relative benefits of early operation (within 3 days) versus late operation (day 10-12), or that of endovascular treatment versus any operation. Antifibrinolytic drugs reduce the risk of rebleeding, but do not improve overall outcome. Measures of proven value in decreasing the risk of delayed cerebral ischaemia are a liberal supply of fluids, avoidance of antihypertensive drugs and administration of nimodipine. Once ischaemia has occurred, treatment regimens such as a combination of induced hypertension and hypervolaemia, or transluminal angioplasty, are plausible, but of unproven benefit.

/pdf/subarachnoid-haemorrhage-diagnosis-causes-and-management-2bxfcfscjw.pdf

Subarachnoid haemorrhage: diagnosis, causes and management

This report describes the development of an experimental head injury model capable of producing diffuse brain injury in the rodent. A total of 161 anesthetized adult rats were injured utilizing a simple weight-drop device consisting of a segmented brass weight free-falling through a Plexiglas guide tube. Skull fracture was prevented by cementing a small stainless-steel disc on the calvaria. Two groups of rats were tested: Group 1, consisting of 54 rats, to establish fracture threshold; and Group 2, consisting of 107 animals, to determine the primary cause of death at severe injury levels. Data from Group 1 animals showed that a 450-gm weight falling from a 2-m height (0.9 kg-m) resulted in a mortality rate of 44% with a low incidence (12.5%) of skull fracture. Impact was followed by apnea, convulsions, and moderate hypertension. The surviving rats developed decortication flexion deformity of the forelimbs, with behavioral depression and loss of muscle tone. Data from Group 2 animals suggested that the cause of death was due to central respiratory depression; the mortality rate decreased markedly in animals mechanically ventilated during the impact. Analysis of mathematical models showed that this mass-height combination resulted in a brain acceleration of 900 G and a brain compression gradient of 0.28 mm. It is concluded that this simple model is capable of producing a graded brain injury in the rodent without a massive hypertensive surge or excessive brain-stem damage.

A new model of diffuse brain injury in rats Part I: Pathophysiology and biomechanics

✓ The incidence and natural history of the cavernous angioma have remained unclear in part because of the difficulty of diagnosing and following this lesion prior to surgical excision. The introduction of magnetic resonance (MR) imaging has improved the sensitivity and specificity of diagnosing and following this vascular malformation. Seventy-six lesions with an MR appearance typical of a presumed cavernous angioma were discovered in 66 patients among 14,035 consecutive MR images performed at the Cleveland Clinic between 1984 and 1989. Follow-up studies in 86% of the cases over a mean period of 26 months provided 143 lesion-years of clinical survey of this condition. The most frequent presenting features were seizure, focal neurological deficit, and headache. While most lesions exhibited evidence of occult bleeding on MR imaging, there was overt hemorrhage in seven of the 57 symptomatic patients and only one overt hemorrhage occurred during the follow-up interval. The annualized bleeding rate was 0.7%. A...

Natural history of the cavernous angioma

Cerebral venous thrombosis.

• Only a few cases of angiographically demonstrated and pathologically proved cases of venous angiomas have been published. In contrast to the scarcity of recorded cases of angiographically studied venous angiomas, they are the most common incidentally encountered angiomatous lesions at autopsy. Their angiographic characterization, though highly suggestive, is not pathognomonic. The angiographic characteristics include small radiating veins that drain into a larger transcerebral vein that in turn empties into a dural sinus; blush and early draining veins also may be seen. The differential diagnosis includes telangiectasia, infiltrating glioma, and probably a cavernous angioma. We report an angiographically demonstrated and pathologically proved case of a venous angioma and also review the literature.

https://jamanetwork.com/journals/NEUR/articlepdf/576545/archneur_35_5_012.pdf

Intracerebral Venous Angioma: Case Report and Review

The presence of the empty delta sign on contrast material-enhanced computed tomographic (CT) scans of the brain is considered pathognomonic of sagittal sinus thrombosis (SST); however, a valid explanation for its appearance is lacking, despite several hypotheses. To determine the frequency of the sign and its prognostic significance, 76 reported cases (112 CT manifestations) of SST and SST-related intracranial sinovenous occlusive disease were reviewed. Ten CT signs related to both disease processes were reported; the empty delta sign was the most frequently reported sign (28.6%) of SST. Patients with hemorrhagic infarction and/or the empty delta sign on CT scans had the poorest prognosis. A case illustrative of the empty delta sign is described in which there was engorgement of endothelial- and nonendothelial-lined spaces in the dura mater with hemorrhagic rupture into the dural leaf. The empty delta sign can probably be explained on the basis of the rich dural venous collateral circulation, consisting p...

The empty delta sign: frequency and significance in 76 cases of dural sinus thrombosis

The common embryologic origin of the septum pellucidum, of the corpus callosum, and of the limbic system explains the anatomic basis of a varying degree of concurrent involvement of these structures in disease processes, both developmental and acquired. Developmental absence of the septum pellucidum portends a more generalized dysplasia that encompasses the corpus callosum and the limbic system. When considered in this context, it is easy to understand the limbic system dysfunction that is engendered by this anomaly. It is rare for an acquired lesion to involve the septum pellucidum per se because of its small size. However, it is common for it to be secondarily involved in almost all types of acquired disease processes. With the exquisite anatomic morphology that MR now provides, one must carefully assess involvement of the septum pellucidum, of the corpus callosum, and of the limbic system in disease processes that occur in the vicinity of these structures, so that more incisive clinical insight into the functions that are subserved by these structures can be obtained.

http://www.ajnr.org/content/ajnr/10/5/989.full.pdf

The septum pellucidum: normal and abnormal.

The pneumatization of 141 "normal" temporal bones on computed tomography (CT) was evaluated in 100 patients (age range, 6-85 years). Because of the controversy surrounding the sclerotic squamomastoid (mastoid), temporal bones with this finding were discarded. A CT index of pneumatization was based on the pneumatized area and the number of cells seen within a representative scanning section. Results suggest that squamomastoid pneumatization follows the classic normal distribution and does not correlate with age, gender, or laterality. A high degree of symmetry was found in 41 patients who had both ears examined. In 35% of all temporal bones, the petrous apex was pneumatized, concordant with the findings of other investigators. Pneumatization extending into other regions of the temporal bone corresponded linearly with squamomastoid pneumatization. Air-cell configuration was variable. Air-cell size tended to increase progressively from the mastoid antrum. The scutum "pseudotumor" appearance caused by incompl...

Computed tomography of temporal bone pneumatization: 1. Normal pattern and morphology.

The clinical and roentgenographic features of 25 cases of colloid cyst of the third ventricle are described. Of all brain tumors, the colloid cyst is one of the most favorable for surgical removal, hence the need for an exact preoperative diagnosis is emphasized. The differential diagnosis is discussed and 2 cases presented to illustrate some pitfalls in the radiological diagnosis of these cysts.

Mohammad Sarwar

Papers

Intracerebral Venous Angioma: Case Report and Review

The empty delta sign: frequency and significance in 76 cases of dural sinus thrombosis

The septum pellucidum: normal and abnormal.

Computed tomography of temporal bone pneumatization: 1. Normal pattern and morphology.

Colloid cysts of the third ventricle.