研究者使用3維磁共振成像去準(zhǔn)確的發(fā)現(xiàn)頸動(dòng)脈壁上出血，一個(gè)會(huì)引發(fā)中風(fēng)的情況

當(dāng)主動(dòng)脈受到動(dòng)脈粥樣硬化，脂肪沉積物，和積累在血管壁內(nèi)部的斑塊的影響。這一系列的疾病隨著時(shí)間導(dǎo)致血管窄化，限制血液流動(dòng)或者導(dǎo)致血管完全被堵塞。直到最近科學(xué)研究者相信這種稱之為狹窄的窄化現(xiàn)象是導(dǎo)致大多數(shù)心臟病和中風(fēng)的原因。但是新的研究顯示混合的結(jié)構(gòu)復(fù)雜的斑塊是形成脈管病癥和死亡的主因。這些斑塊有表面潰瘍，血塊和在血管壁內(nèi)出血的特征“在我們的研究中將有一個(gè)巨大的改變” 多倫多大學(xué)的艾倫.R.穆迪先生談到：“我們現(xiàn)在已經(jīng)知道頸動(dòng)脈中混合斑塊可能是導(dǎo)致中風(fēng)的前兆，并且數(shù)量超過血管狹窄。”
這個(gè)最新的研究結(jié)果提出3-D磁共振成像技術(shù)可能被證明能是一種對判斷有高中風(fēng)風(fēng)險(xiǎn)的患者有用的影像工具。在研究中研究者使用3—D磁共振成像對11名年齡在60-81的頸動(dòng)脈疾病患者進(jìn)行了試驗(yàn)。這些頸動(dòng)脈斑塊通過手術(shù)從這些患者的患病動(dòng)脈被取出并通過顯微鏡進(jìn)行了分析。
這個(gè)研究小組發(fā)現(xiàn)被磁共振識別的病變器官和用顯微鏡分析的組織樣本高度一致。“用高分辨率的3-D磁共振技術(shù)，我們可以不通過介入去分析動(dòng)脈壁內(nèi)的組織，并發(fā)現(xiàn)也許會(huì)導(dǎo)致患者中風(fēng)風(fēng)險(xiǎn)的在斑塊內(nèi)的細(xì)微的出血”穆迪談到。
根據(jù)穆迪所介紹，3-D磁共振成像是一個(gè)理想用于篩選高風(fēng)險(xiǎn)結(jié)構(gòu)復(fù)雜的頸動(dòng)脈斑塊的患者的工具并且監(jiān)測介入的影響，減緩動(dòng)脈粥樣硬化疾病的發(fā)展。這項(xiàng)技術(shù)可以簡單的被說明和應(yīng)用。加載到血管造影技術(shù)研究只需要幾分鐘的時(shí)間。

Diagnosis: 3-D MRI Finds High-Risk Carotid Disease

Researchers have used three-dimensional magnetic resonance imaging (3-D MRI) to accurately detect bleeding within the walls of diseased carotid arteries, a condition that may lead to a stroke.
When major arteries are affected by atherosclerosis, fatty deposit, or plaques, accumulate on the inner lining of the vessel walls. Progression of the disease over time leads to narrowing, restricting blood flow or becoming completely blocked. Until recently, scientists believed that this narrowing, called stenosis, was responsible for most heart attacks or strokes.

But new studies have identified the composition of complicated plaques as being a major cause of vascular events and deaths. These plaques are characterised by surface ulcerations, blood clots and bleeding into the vessel wall. "There's been a major sea change in our research," said Alan R. Moody of the University of Toronto. "We now know that the composition of carotid artery plaque is likely to be more predictive of future stroke events than the amount of stenosis in the vessel."

The results of the new study suggest the 3-D MRI technique may prove to be a useful screening tool for patients at high risk for stroke. In the study, researchers performed 3-D MRI on the carotid arteries of eleven patients, age 69 to 81. Complicated plaques were then surgically removed from the patients' diseased arteries and analysed under a microscope.

The research team found strong agreement between the lesions identified by MRI as complicated plaques and the microscopic analysis of the tissue samples. "With high spatial resolution 3-D MRI, we are able to noninvasively analyse the tissue within the artery wall and identify small bleeds within rupture-prone plaques that may put patients at risk for future stroke," Moody said.

According to Moody, 3-D MRI is a tool that is ideally suited to screen high-risk patients for complicated carotid plaques and to monitor the effect of interventions designed to slow the progress of the atherosclerotic disease. The technique is easy to perform and interpret and takes only a few minutes when added to an MR angiography study, he said.