Segmentation of 3D image of cerebral vessel / 国际生物医学工程杂志

During surgery and radiation therapy,demands for higher quality of quantification and visualization of cerebral vessels need to be met.Hence,automatic (or semi-automatic) extractions of accurate cerebral vessel information seem particularly important.This paper reviews the cerebral vessel segmentation methods used in recent years,including statistics-based segmentation,deformable model,multi-scale method,prior knowledgebased method,and so on.The methods are divided into the following three categories:voxel intensity based approach,vascular tubular structure based approach,and prior knowledge-based approach.

Cerebral ischemia and opioids / 中国药理学通报

Opioid peptides and their receptors play an important role in the pathophysiologic process of stroke. The concentration of endogenous opioid peptides elevates, while the density of opioid receptors decreases in CNS during cerebral ischemia; on the other hand, opioids influence the development of stroke through regulating the contraction of cerebral vessel, immuno-endocrine system and neuroprotection against injury. Thus, drugs that regulate the opioid system may be a new therapeutic approach for prevention and treatment of cerebral ischemia.

Some observations on clinical and paraclinical characteristics of malformation of cerebral vessel in children

In Bach Mai Hospital from May 1998 to June 2002, 23 children aged 10-15 (15 girls and 8 boys) with malformation of brain vessel were diagnosed definitely. Most of under 11-year-old children have swelling vessel, 30.4% of above 11-year-old children have AVM malformation - 52.1%. The main manifestations of brain vessel malformation are hemorrhage of brain lobe 65.2%, subarachroid hemorrhage 39.1%, brain ischemia 30.4%, epilepxy or epileptic conditions 21.7%, head pain of migraine type 17.4%. Unilateral palsy of III nerve is specific sign for diagnosis of swelling of prosterior communicating artery with a rate of 8.7%. Dysphasia is temporary, while the visual dysfunction is more persistent

The Comparison of CT Angiography(CTA) and DSA in Neurovascular Disease / 实用放射学杂志

Objective To assess the value of CTA and DSA in neurovascular diseases.Methods 20 cases with suspected neurovascular disorders who received CTA and DSA examination between March 1999 and August 2000 were retrospectively collected.The sensitivity,specifility and accurate rate of CTA were analysed compared with DSA as gold standard.Results In 20 cases,neurovascular disorders were found in 17 on CTA.18 lesions were detected,including 6 aneurysms,9 arteriovenous malformations(AVM),2 carotid cavernous fistulae(CCFs)and 1 arterial stenosis.By contrast,19 lesions in 17 cases were detected by DSA,including 7 aneurysms,8 AVMs,2 arterial stenoses and 2 CCFs.The sensitivity,specificity and accuracy of CTA in the detection of neurovascular disorders were 90.6%,95.2% and 90.6% respectively.Conclusion 3D-CTA is a new modality with high sensitivity and specificity in the detection of neurovascular disorders.As it can be obtained simply,conveniently and safely with mild injury to the patient,CTA can be used in the diagnosis of neurovascular diseases,especially in the AVMs.

Size Differences of Major Cerebral Vessels in a Variety of Cerebrovascular Diseases with Changed Blood Flow

It has been known that the size of arterial diameter during growth in primates is closely dependent on blood flow. Flow induced arterial size can be influenced by contractile or structual characters of vascular smooth muscle cells. Furthermore it had been confirmed through experimental study that vascular endothelium releases vasoactive substances which adjust smooth muscle tone, and could detect shear stress on the vascular wall by its direct contact with luminal flow. The authors tried to prove it through the angiographic measurement of the major vessel sizes in cerebrovascular diseases with changed blood flow. We measured the major vessel sizes of 36 cases of cerebrovascular diseases:arteriovenous malformation in 14 cases, cerebral infarction in 8, cerebral hemiatrophy in 6 moyamoya disease 5, occlusion of the internal carotid artery in 2, and carotid-cavernous fistula in 1, which may influence cerebral blood flow, on angiography under the same circumstances. Results are as the followings: 1) In the cases of arteriovenous malformation and carotid-cavernous fistula, all of the major vessel sizes of the lesion wite were increased and all became decreased postoperatively. 2) In the cases of major vessel occlusion and cerebral hemiatrophy, the major vessel size of the lesion site was smaller than that of the normal site. 3) In the cases of moyamoya disease, there was no definite size different between both ICA sizes. In conclusion, the change in cerebral blood flow is a determinant factor of the major vessel sizes in the cases of cerebrovascular disorders which an influence cerebral blood flow.

Study the Effects of Herba Siegesbeckiae Capsule on Cerebral Blood Flow and Cerebral Vessel Resistance in Anesthetized Dogs / 中国药房

OBJECTIVE:To study the effect of Herba Siegesbeckiae capsule on cerebral blood flow (CBF), cerebral vessel resistance (CVR), blood pressure (BP), electrocardiogram (ECG) and heart rate (HR)in anesthetized dogs. METHODS: The external carotid arteries on one side and the vertebral arteries of dogs were ligated, then the CBF of carotid arteries was measured by electromagnetic flowmeter, and the BP, EGG and HR were measured by polygraph. RESULTS: Herba Siegesbeckiae capusle could significantly increase CBF and decrease CVR; however, it has no effect on BP, ECG and HR. CONCLUSION: Herba Siegesbeckiae capsule can improve cerebral blood circulation through increasing CBF and decreasing CVR.

Cerebral ischemia and opioids / 中国药理学通报

Opioid peptides and their receptors play an important r ole in the pathophysiologic process of stroke. The concentration of endogenous o pioid peptides elevates, while the density of opioid receptors decreases in CNS during cerebral ischemia; on the other hand, opioids influence the development o f stroke through regulating the contraction of cerebral vessel, immuno-endocrin e system and neuroprotection against injury. Thus, drugs that regulate the opioi d system may be a new therapeutic approach for prevention and treatment of cereb ral ischemia.

THE CHANGES OF ENDOTHELIN-A RECEPTOR mRNA IN THE CEREBRAL BASILAR ARTERY OF RATS WITH SUBARACHNOID HEMORRHAGE / 解剖学报

Objective To detect the changes of Endothelin-A receptor mRNA in the cerebral basilar artery of rats with experimental subarachnoid hemorrhage-induced cerebral vessel spasm as well as its effect. Methods Fifty-six Wistar rats were randomly divided into normal, experimental,sham-operated and saline-control groups. The experimental group was subdivided into subarachnoid hemorrhage(SAH)2,3,7 and 14?d groups. Reverse transcription polymerse chain reaction was used to study the changes of Endothelin-A receptor mRNA level in the cerebral basilar artery of rats with experimental subarachnoid hemorrhage-induced cerebral vessel. Results ET-A receptor mRNA level of basilar artery in SAH2, 3?d and 7?d group was higher obviously than that of normal group,sham-operated and saline-control groups. That of 14?d group was approximate to normal group.Conclusion ET-A receptor may play an important role in pathogenesis of SAH-induced cerebral vessel spasm.

THE PEPTIDERGIC INNERVATION OF CEREBRAL VESSELS——LIGHT MICROSCOPIC AND IMMUNOELECTRON MICROSCOPIC STUDY / 解剖学报

Using the immunohistochemical and immunoelectron microscopic methods, the localization and pattern of vasoactive intestinal polypeptidergic nerves in the wall of cerebral vessels were investigated. The results revealed that the VIP-like immunoreactive (VIPLI) fibres were located in the adventitia or at the adventitia-media border. No synaptic contacts were identified among the nerve terminals or between nerve terminal and smooth muscle cell. VIPLI terminals directly apposed to the smooth muscle cells with a distance of 100 nm.The observations mentioned above indicate that there is peptidergic innervation in the wall of the cerebral vessels besides traditional adrenergic and cholinergic innervations. The regulatory function of VIP-containing nerves to the cerebral vessels may be performed by affecting the smooth muscle directly through the nonsynaptic release. In addition, present study identified and discussed the distribution and function of substance P(SP) in the cerebral vessels.