主動脈病變CT診斷PPT參考課件

1、主動脈病變的CT診斷,朱曉梅,1,主動脈病變診斷常用方法 CT，經(jīng)食管超聲，MR，主動脈造影 多排螺旋CT的發(fā)展，CTA已經(jīng)成為首選的診斷手段 CTA在診斷方面，優(yōu)于DSA 無創(chuàng) 三維 顯示管壁，周圍結(jié)構(gòu),2,2020/8/29,CT掃描技術(shù),掃描范圍：主動脈弓上3cm到兩側(cè)股骨頭水平（股動脈） 120KV，120mAs；低KV，低mAs噪音增加，但不影響診斷 升主動脈建議ECG-gateing 升主動脈假夾層：右前緣和左后緣 ECG-gating增加放射劑量,3,2020/8/29,主動脈搏動偽影,4,2020/8/29,of 100cm,Scan protocols for CTA of

2、the entire aorta with a range of 100cm for different Siemens scanners (Somatom Volume Zoom, Somatom Sensation 16 and sensation 64),5,2020/8/29,對比劑注射方案,主動脈內(nèi)密度：200HU 高濃度，高流速 350mg I/ml-400mg I/ml 3-4ml/s 劑量：根據(jù)患者體重及掃描持續(xù)時間確定 進(jìn)床速度與對比劑流動的一致性 進(jìn)床太快：遠(yuǎn)端動脈充盈欠佳 進(jìn)床過慢：錯失動脈內(nèi)對比劑高峰時間,6,2020/8/29,對比劑注射方案,雙筒注射器 生理鹽水沖洗

3、 減少上腔靜脈內(nèi)的條狀偽影 改善對比劑拖尾效應(yīng)，減少對比劑用量 增強(qiáng)對比劑的團(tuán)注效應(yīng) 延遲時間： test bolus bolus tracking 固定延遲時間（基本廢除）,7,2020/8/29,圖像后處理,原始斷層最重要 分節(jié)分段顯示 后處理圖像提示診斷 MIP，MPR，VR，CPR等 顯示畸形，走形：VR 血管內(nèi)腔及管壁：MIP，MPR 去骨和不去骨都重要,8,2020/8/29,主動脈解剖,升主動脈： 主動脈根部（主動脈竇），升主動脈 主動脈弓（無名動脈開口-動脈導(dǎo)管或動脈韌帶） 左側(cè) 右位主動脈弓，多伴有心臟畸形 無名動脈，左頸總動脈，左鎖骨下動脈（迷走） 降主動脈 主動脈弓與降主

4、動脈連接處：主動脈峽部,9,2020/8/29,主動脈解剖,胸部降主動脈 腹主動脈 腹腔干 根部受韌帶壓迫常會比較細(xì) 變異較多 腸系膜上動脈 診斷分支閉塞時，厚MIP或VR重要 腸系膜下動脈 腎動脈 檢查腎動脈變異時，掃描范圍要廣,10,2020/8/29,11,2020/8/29,主動脈先天變異,主動脈離斷 定義：升主動脈和降主動脈分離 分型（離斷點(diǎn)定分型） Type A：左鎖骨下動脈遠(yuǎn)端 Type B：左頸總動脈遠(yuǎn)端 Type C：左頸總動脈近端 右側(cè)頸總動脈起始 可正常也可異常 常見異常：起源于左側(cè)鎖骨下動脈遠(yuǎn)端（迷走右側(cè)鎖骨下動脈）,12,2020/8/29,主動脈先天變異,主動脈縮窄

5、 常見位置：左鎖骨下動脈遠(yuǎn)端（主動脈峽部） 分型 管型 局限型 縮窄遠(yuǎn)端，主動脈管腔常擴(kuò)張 右側(cè)迷走鎖骨下動脈長起源于狹窄遠(yuǎn)端,13,2020/8/29,主動脈先天變異,主動脈縮窄 管型縮窄 可以無癥狀，偶然發(fā)現(xiàn) 癥狀：高血壓引起頭痛；遠(yuǎn)端血運(yùn)差導(dǎo)致陂行 嚴(yán)重縮窄：3-5歲需手術(shù) 術(shù)前CTA：顯示縮窄的部位和程度，近端升主動脈擴(kuò)張，有無伴發(fā)的動脈瘤，有無心臟畸形 術(shù)后CTA：測量主動脈內(nèi)徑觀察恢復(fù)情況 測量時，一定要MIP重建，垂直于血管長徑測量內(nèi)徑 比較內(nèi)徑大小時，考慮年齡增長因素，一般1mm/y,14,2020/8/29,Sagittal reformatted CT image demo

6、nstrating a membranous septation (arrow) distal to the left subclavian artery in a patient with a classic aortic coarctation,15,2020/8/29,主動脈先天變異,主動脈憩室 定義： 右側(cè)迷走鎖骨下動脈起始的主動脈彈性擴(kuò)張 部位： 左側(cè)鎖骨下動脈起始遠(yuǎn)端 癥狀： 右側(cè)迷走鎖骨下動脈壓迫食管引起吞咽困難,16,2020/8/29,主動脈先天變異,右位主動脈弓 通常無癥狀 常伴左側(cè)迷走鎖骨下動脈 分支與正常呈鏡像時：常伴有心臟畸形 左側(cè)鎖骨下動脈離斷時：先天性鎖骨下動脈盜

7、血癥（左上肢動脈搏動減弱）,17,2020/8/29,(A) Axial CT image demonstrating a right aortic arch (asterisk). (B) The right common carotid (black arrow) and the right subclavian (white arrow) arteries have separate origins at the aortic arch. There is a common trunk (arrowhead) of the left common carotid (CCA) and le

8、ft subclavian (LSA) arteries. (C) Coronal reformat image demonstrates a saccular aneurysm of the ascending aorta (asterisk). The origin of the common trunk of the left CCA and LSA is also seen (arrow).,18,2020/8/29,主動脈瘤,定義 局限性，持久性，主動脈全層擴(kuò)張，超過正常內(nèi)徑的50% 擴(kuò)張不到50%：主動脈擴(kuò)張 原因 動脈粥樣硬化：最常見 感染 主動脈中膜壞死囊變,19,2020/8

9、/29,主動脈瘤,常見的伴發(fā)致死因素 高血壓，冠心病，阻塞性肺疾病，心衰 動脈粥樣硬化動脈瘤 梭形 腹部降主動脈多發(fā) 馬凡綜合癥 升主動脈，累及主動脈環(huán) 梨形升主動脈,20,2020/8/29,主動脈瘤,CTA 部位 最大徑 長度 累及的重要血管分支 內(nèi)徑大約6cm 易形成夾層，破裂 腹主動脈瘤 人口老齡化，發(fā)病率增加 無癥狀，破裂致死率增加 高危險人群，建議篩查：吸煙，高血壓，男性，大于65歲，家族史,21,2020/8/29,主動脈瘤,腹主動脈假性動脈瘤： 醫(yī)源性最多見 支架植入術(shù) 下腔靜脈濾器植入術(shù) 心臟移植術(shù) 外傷 感染破裂,22,2020/8/29,(A) Axial CT imag

10、e in a patient with a chronic aortic pseudoaneurysm. The thick pseudocapsule formed by blood and fibrotic tissue is invading the thoracic vertebrae resulting in bone resorption. (B) Sagittal reformat CT image demonstrates a narrow neck connecting the aorta and the sac of the pseudoaneurysm (arrow).,

11、23,2020/8/29,主動脈瘤,主動脈瘤破裂 定義：主動脈壁全層不連續(xù) 致死率：院外，90% 原因： 復(fù)雜，多因素 主動脈內(nèi)徑，擴(kuò)張率，舒張壓，主動脈壁所受的剪切力和強(qiáng)度，內(nèi)壁血栓和血管壁彈性改變等 破裂位置：主動脈后壁最常見,24,2020/8/29,主動脈瘤,主動脈瘤破裂 CT特點(diǎn) 特征性改變：造影劑外漏 其他： 主動脈壁不連續(xù) 與主動脈分界不清的軟組織狀況腫塊 腰大肌邊緣模糊 內(nèi)臟移位,25,2020/8/29,主動脈瘤,主動脈瘤破裂 局限性主動脈破裂 特點(diǎn)：主動脈旁軟組織腫塊邊緣較清晰 積極篩查和隨訪高危人群，在主動脈破裂前采取措施，減低死亡率,26,2020/8/29,Axial

12、 CT image demonstrating an abdominal aortic aneurysm (AAA), which has ruptured retroperitoneally with resultant hematoma (asterisk).,27,2020/8/29,主動脈瘤,感染性主動脈瘤 發(fā)病率：0.7%-2.6% 感染路徑：原發(fā)灶播散，外傷，醫(yī)源性因素 與動脈粥樣硬化性動脈瘤相比：進(jìn)展快 CT特點(diǎn)：主動脈旁軟組織腫塊，索條影，積液,28,2020/8/29,主動脈瘤,腹主動脈瘤處理 手術(shù)： 內(nèi)徑5cm 內(nèi)徑4.5cm, 半年內(nèi)徑增加大約0,5cm,29,2020/

13、8/29,Axial CT image in a patient with tuberculosis in the posterior segment of the lower lobe of the left lung. A pseudoaneurysm (asterisk) of the descending thoracic aorta has developed due to necrosis of the aortic wall.,30,2020/8/29,Axial CT image demonstrating a mycotic aneurysm of the descendin

14、g thoracic aorta with periaortic soft-tissue mass (arrowhead) and fluid (arrow).,31,2020/8/29,主動脈夾層動脈瘤,致死率高 累及升主動脈成活率低于僅累及降主動脈患者 影響因素 高血壓 馬綜合征，Turner 綜合征，結(jié)締組織病，先天性主動脈瓣膜缺陷，主動脈縮窄，主動脈瘤，主動脈炎，妊娠，可卡因等 分型 Standford分型：A型和B型 Debakey分型：I型，型和型,32,2020/8/29,Diagram illustrating the DeBakey and Stanford Systems

15、of classification of aortic dissection.,33,2020/8/29,主動脈夾層動脈瘤,急性：周；慢性：周 患者死亡多在急性期 累及頸總動脈時可引起大面積腦梗死 二聚體和凝血酶-抗凝血酶復(fù)合物 與夾層動脈瘤形狀改變呈線性關(guān)系 可以用來慢性患者的隨訪,34,2020/8/29,主動脈夾層動脈瘤,Type A： 并發(fā)癥：心包積液（心包填塞），胸腔積液，累及冠狀動脈和主動脈環(huán) 致死率高，需要立即手術(shù)治療 Type B 致死率低 致死三聯(lián)征：低血壓/休克，無胸痛，分支受累,35,2020/8/29,主動脈夾層動脈瘤,Type B 一般，積極控制血壓，擇期介入治療 隨

16、訪 受累主動脈直徑易增大 胸主動脈增長較腹主動脈快 大于60歲 假腔內(nèi)有血流 破裂，分支閉塞或變大，需緊急手術(shù)或介入治療 TypeA和Type B手術(shù)治療 并發(fā)癥： 分支開口受阻致供血不足 處理：主動脈內(nèi)膜開窗術(shù),36,2020/8/29,主動脈夾層動脈瘤,CT表現(xiàn) 平掃，增強(qiáng)都很重要 平掃 鈣化的內(nèi)膜內(nèi)移 管腔內(nèi)密度正常 急性期，假腔高密度影 需與動脈瘤內(nèi)膜鈣化伴血栓形成鑒別 管腔內(nèi)密度增高,37,2020/8/29,主動脈夾層動脈瘤,CT增強(qiáng)表現(xiàn) 內(nèi)移內(nèi)膜片 真腔，假腔 真腔假腔鑒別 必要性：支架必須在真腔 假腔：蜘蛛網(wǎng)征(cobweb sign), 鳥嘴征，兩端是盲端，易發(fā)附壁血栓 真腔

17、：與近端和遠(yuǎn)端管腔連續(xù)，外壁鈣化（慢性期，假腔外壁偶可鈣化），離心性內(nèi)膜片鈣化,38,2020/8/29,主動脈夾層動脈瘤,CT增強(qiáng)表現(xiàn) 真腔假腔鑒別 上四分之一處 假腔較大（85%） 內(nèi)膜片： 急性期：凸向假腔（56%），平直（38%），凸向真腔（6%） 慢性期：平直（75%），凸向假腔（25%） 中段水平 假腔大（94%） 內(nèi)膜片 急性期：平直（37%），凸向假腔（33%），凸向真腔（30%） 慢性期：平直（67%），凸向假腔（29%），凸向真腔（4%） 下四分之一處 假腔大（91%） 內(nèi)膜片 急性期：平直（33%），凸向假腔（39%），凸向真腔（28%） 慢性期：平直（100%）,39,

18、2020/8/29,主動脈夾層動脈瘤,CT增強(qiáng)表現(xiàn) 真腔假腔鑒別 真腔：對比劑早到早走，峰值較高 假腔：對比劑遲到遲走，峰值較低 急性期和慢性期鑒別 急性期： 上四分之一處和下四分之一處，內(nèi)膜片凸向假腔 慢性期： 內(nèi)膜片鈣化，假腔外壁鈣化，假腔內(nèi)附壁血栓,40,2020/8/29,(A) Axial CT image in a patient with a Type A aortic dissection. The true lumen (arrowhead) is smaller and of higher density than the false lumen (arrow). (B)

19、Coronal reformat image demonstrates extension of the dissection flap into the innominate and right common carotid arteries (arrow).,41,2020/8/29,(A) Sagittal reformat CT image in a patient with Marfan syndrome demonstrating a type A aortic dissection involving the entire length of the aorta. (B) Axi

20、al CT image at the level of the main pulmonary artery showing involvement of the ascending and descending thoracic aorta. The larger cavity is the false lumen with a lower density (arrows) while the true lumen is smaller with a higher density (arrowheads).,42,2020/8/29,41-year-old man with acute aor

21、tic dissection. CT scan obtained at one-quarter distance along length of dissected portion of aorta shows descending aortic dissection flap (arrows) that is curved toward false lumen (F). Beak sign (arrowheads) is present in false lumen. Note that false lumen area is larger than true lumen area.,43,

22、2020/8/29,51-year-old woman with chronic aortic dissection. CT scan obtained at one-half distance along length of dissected portion of aorta shows flat dissection flap. False lumen beaks are filled with lowattenuation thrombus (arrowheads). Faintly visualized cobweb (arrows) is present in false lume

23、n (F).,44,2020/8/29,65-year-old woman with chronic aortic dissection. CT scan obtained at one-quarter distance along length of dissected portion of aorta shows flat dissection flap. Outer wall calcification (straight arrow) is present in true lumen (T). Thrombus (arrowheads) is present in false lume

24、n. Curved arrow indicates thrombus within false lumen beak.,45,2020/8/29,76-year-old man with chronic aortic dissection. CT scan obtained at three-quarters distance along length of dissected portion of aorta shows flat dissection flap. Outer wall calcification (arrows) and thrombus (asterisk) are pr

25、esent in false lumen (F). T = true lumen.,46,2020/8/29,59-year-old man with chronic aortic dissection. CT scan obtained at one-quarter distance along length of dissected portion of aorta shows flat dissection flap. Eccentric flap calcification (arrow) is present along true lumen side of flap. Notice

26、 that false lumen (F) contains thrombus (arrowheads) and is larger than true lumen at this level.,47,2020/8/29,Unenhanced axial CT image (A) demonstrates displacement of the calcified intima (arrow) which corresponds to the intimal flap (arrowhead) on the contrast-enhanced CT (B). The true lumen (TL

27、) is brightly enhancing, while the false lumen (FL) is partially enhancing and to a lesser degree due to slower flow and thrombosis.,48,2020/8/29,65-year-old man with acute aortic dissection. CT scan obtained at one-quarter distance along length of dissected portion of aorta shows dissection flap th

28、at is curved toward true lumen. Anterior false lumen beak (arrowheads) is partially opacified and partially filled with thrombus. F = false lumen.,49,2020/8/29,7.69-year-old woman with acute aortic dissection. CT scan obtained at level of transverse aortic arch shows that outer false lumen (F) wraps

29、 around inner true lumen (T). Dissection flap extends into innominate artery. Note cobweb in false lumen (arrow) and bilateral pleural effusions (P).,50,2020/8/29,(A) Axial CT image in a patient with an acute Type B aortic dissection. The right kidney is less enhanced than the left kidney due to slo

30、wer blood flow through the right renal artery which originates from the false lumen of the aorta (arrow). (B) Axial CT image in a different patient demonstrating a chronic Type B aortic dissection. Long-standing decreased perfusion to the left kidney due to obstruction of the left renal artery origi

31、n (arrowhead) by the dissection flap has caused atrophy of the left kidney. The right kidney shows compensatory hypertrophy.,51,2020/8/29,主動脈膜內(nèi)血腫,夾層動脈瘤早期或不典型夾層動脈瘤 中膜內(nèi)滋養(yǎng)血管破裂出血，內(nèi)膜片完整，無破口 急性夾層動脈瘤，13%為膜內(nèi)血腫 分型：Stanford分型 CT表現(xiàn) 平掃：新月形稍高密度影 增強(qiáng)：膜內(nèi)血腫密度多變，可高可低,52,2020/8/29,(A) Axial CT image in a patient with

32、a Type A IMH involving the ascending and descending thoracic aorta. Curvilinear hypodensities correspond to the intramural hematoma (arrows). (B). Axial CT image in a patient with a Type B IMH (arrow) with calcified aortic adventitia (arrowhead). (C) Axial CT image in a patient with a Type B IMH wit

33、h extensive hematoma (arrow) circumferentially within the wall of aorta.,53,2020/8/29,主動脈粥樣硬化,老年代謝性疾病，女性絕經(jīng)后進(jìn)展迅速 主動脈穿透性潰瘍（penetrating aortic ulcer，PAU） 粥樣斑塊侵蝕主動脈壁內(nèi)層和彈性膜，中膜內(nèi)血腫形成 可致主動脈瘤形成或主動脈破裂 囊狀動脈瘤多PAU引起 多發(fā)生在老齡患者，動脈粥樣硬化較重 主動脈弓和降主動脈多見，升主動脈少見,54,2020/8/29,Diagrams illustrate the four stages in the form

34、ation of a penetrating atherosclerotic ulcer: (A) aortic atheroma, (B) benign intimal plaque ulceration contained in the intima, (C) medial hematoma with potential adventitial false aneurysm, and (D) transmural rupture.,55,2020/8/29,主動脈粥樣硬化,PAU治療 隨訪 手術(shù)： 適應(yīng)癥：血流動力學(xué)不穩(wěn)定，持續(xù)疼痛，主動脈破裂，遠(yuǎn)端栓塞，主動脈直徑快速增大 難度大，并發(fā)癥

35、多 PAU CT表現(xiàn) 粥樣斑塊局部潰瘍形成，主動脈管腔局部尖角樣突起 可單發(fā)或多發(fā),56,2020/8/29,Aortic changes due to atherosclerosis in different stages. (A) Aortic atheroma, (B) benign intimal plaque ulceration (white arrow) contained in the intima and (C) medial hematoma (white arrow) with potential adventitial false aneurysm.,57,2020/8

36、/29,外傷性主動脈損傷,主動脈不完全破裂 主動脈完全破裂 外傷性主動脈夾層動脈瘤 外傷性主動脈膜內(nèi)血腫,58,2020/8/29,外傷性主動脈損傷,CT表現(xiàn) 縱隔內(nèi)積血 主動脈變形 內(nèi)移的內(nèi)膜片 主動脈內(nèi)血栓 假性動脈瘤 降主動脈逐漸變細(xì),59,2020/8/29,(a) CT scan shows a crescent of periaortic blood surrounding the descending aorta(arrow). (b) CT scan shows a contour deformity, compatible with a pseudoaneurysm, nea

37、r the ligamentum arteriosus (arrow).,60,2020/8/29,Aortic transection in a 39-year-old woman following blunt trauma to the chest. (a) CT scan demonstrates blood in the mediastinum and around the aorta. An intimal flap is present in the descending aorta (arrow). (b) On another scan obtained at a lower

38、 level, luminal debris and aortic contour irregularity are noted.,61,2020/8/29,Acute blunt chest trauma. Axial CT scans (a, b) show a small amount of blood in the anterior mediastinum but a normal aortic contour. The sternal fracture (arrowhead in b) is the source of blood.,62,2020/8/29,(A) Axial CT image demonstrating a contained traumatic aortic transection. A pseudoaneurysm (arrow) has formed at the site of the aortic wall disruption and the arch is surrounded by a hem