【正文】 位內(nèi)膜血漿脂蛋白的內(nèi)流和聚集； 局部?jī)?nèi)膜單核細(xì)胞巨噬細(xì)胞修復(fù)； 在內(nèi)膜通過(guò)(tōnggu242。纖維母細(xì)胞生長(zhǎng)因子可能調(diào)節(jié)平滑肌細(xì)胞增殖； 斑塊破裂主要在巨噬細(xì)胞最密集部位。,第二十八頁(yè)，共一百一十七頁(yè)。,E： 動(dòng)脈粥樣硬化(y236。)的形成,圖片(tn)7a,第三十頁(yè)，共一百一十七頁(yè)。pi224。,F： Time window,血管閉塞3～6個(gè)小時(shí)內(nèi)恢復(fù)血流，腦梗死還可能挽救，超過(guò)這段時(shí)間后恢復(fù)血流，不但難于挽救腦細(xì)胞，還可能引起再灌流損傷(sǔnshāng)，繼發(fā)出血、腦水腫，這段時(shí)間稱(chēng)為復(fù)流治療時(shí)間窗（Time window）。,G： 缺血瀑布理論 近年發(fā)現(xiàn)腦缺血、缺氧造成的能量代謝障礙(zh224。i)—興奮性神經(jīng)介質(zhì)釋放—鈣過(guò)量?jī)?nèi)流—自由基反應(yīng)—細(xì)胞死亡等一系列缺血性連鎖反應(yīng)，是導(dǎo)致缺血性腦損害的中心環(huán)節(jié)，稱(chēng)之為缺血瀑布。,迅速溶栓復(fù)流是大片腦梗死急性期治療成功的前提和基礎(chǔ) 腦保護(hù)打斷反應(yīng)鏈則是治療成功的基本保證。沒(méi)有溶栓復(fù)流，即使用最有效的腦保護(hù)方法和藥物，最終也不能挽救持續(xù)缺血的腦組織； 而單靠溶栓復(fù)流，沒(méi)有針對(duì)(zhēndu236。,第三十四頁(yè)，共一百一十七頁(yè)。n li有的白細(xì)胞甚至(sh232。)游出血管外,直接損傷腦組織. 出血性梗死:血管再通后,梗塞血管通透性增加甚至壞死,血液滲出血管外,這種情況特別容易發(fā)生在治療時(shí)間窗后血管再通. 鑒于再灌流損傷和出血性梗死皆易發(fā)生在治療時(shí)間窗后血管再通,故溶栓治療要嚴(yán)格掌握治療時(shí)間窗.,第三十五頁(yè)，共一百一十七頁(yè)。x236。,A: 我們先看幾張前循環(huán)(xn)梗塞片,圖片(tn)8,第三十七頁(yè)，共一百一十七頁(yè)。ngm224。pi224。,MCA infarction: on CT an area of hypoattenuation appearing within six hours is highly specific for irreversible ischemic brain damage,圖片(tn)10,第三十九頁(yè)，共一百一十七頁(yè)。,Hemorrhage is most easily detected with CT, but it can also be visualized with gradient echo MRsequences. 采用梯度回波MRI序列檢測(cè)超早期(zǎoqī)腦實(shí)質(zhì)出血的準(zhǔn)確性與CT相當(dāng),圖片(tn)11,第四十一頁(yè)，共一百一十七頁(yè)。pi224。,Insular Ribbon sign This refers to hypodensity and swelling of the insular cortex. It is a very indicative and subtle early CTsign of infarction in the territory of the middle cerebral artery. This region is very sensitive to ischemia because it is the furthest removed from collateral flow.,圖片(tn)13,第四十三頁(yè)，共一百一十七頁(yè)。xi224。預(yù)示著大面積MCA梗死。,Dense MCA sign This is a result of thrombus or embolus in the MCA. On the left a patient with a dense MCA sign. On CTangiography occlusion of the MCA is visible.,圖片(tn)14,第四十五頁(yè)，共一百一十七頁(yè)。pi224。,CT Perfusion (CTP) With CT and MRdiffusion we can get a good impression of the area that is infarcted, but we cannot preclude a large ischemic penumbra (tissue at risk). With perfusion studies we monitor the first pass of an iodinated contrast agent bolus through the cerebral vasculature. Perfusion will tell us which area is at risk. Approximately 26% of patients will require a perfusion study to come to the proper diagnosis. The limitation of CTperfusion is the limited coverage.,圖片(tn)16,第四十七頁(yè)，共一百一十七頁(yè)。pi224。,On the left three consecutive CTimages of a patient with an occlusion of the right internal carotid artery. The hypoperfusion in the right hemisphere resulted in multiple internal border zone infarctions. This pattern of deep watershed infarction is quite common and should urge you to examine the carotids. See the article on Multiple Sclerosis for the differentiation between internal border zone infarctions, lacunar infarctions and MS.,deep watershed infarction 分水嶺梗塞(gěngs232。pi224。,B: 左大腦(d224。pi224。,上圖,綜合典型的脫髓鞘改變和腦萎縮，診斷應(yīng)該為皮層下動(dòng)脈硬化性腦病更為(ɡ232。i)明確一點(diǎn)。,C: 丘腦梗塞,圖片(tn)19,第五十二頁(yè)，共一百一十七頁(yè)。,D: 大腦(d224。pi224。,圖片(tn)21,第五十五頁(yè)，共一百一十七頁(yè)。pi224。,圖片(tn)23,第五十七頁(yè)，共一百一十七頁(yè)?；讋?dòng)脈主干閉塞常引起廣泛的橋腦梗塞，可突發(fā)眩暈、嘔吐、共濟(jì)失調(diào)，迅速出現(xiàn)昏迷、面部與四肢癱瘓，去腦強(qiáng)直、眼球固定、瞳孔縮小、高熱、甚至呼吸及循環(huán)衰竭死亡。,圖片(tn)24,第五十九頁(yè)，共一百一十七頁(yè)。pi224。,圖片(tn)26,第六十一頁(yè)，共一百一十七頁(yè)。pi224。,圖片(tn)28,第六十三頁(yè)，共一百一十七頁(yè)。pi224。,圖片(tn)30,第六十五頁(yè)，共一百一十七頁(yè)。pi224。,圖片(tn)32