【作者】 何其舟；

【导师】 唐光才；

【作者基本信息】 泸州医学院 ， 影像医学与核医学， 2011， 硕士

【摘要】 目的：运用64层螺旋CT血管成像(64-SCTA)研究肠系膜上动脉(SMA)正常影像解剖与变异,评价64-SCTA对SMA的显示能力,探讨SMA各种常见病变的影像特征与临床应用。资料与方法：收集SMA及其分布区域无病变影响的病例资料164例；SMA及与之相关的病变48例。所有病例行64-SCTA,原始数据进行薄层0.625mm重建后,传入ADW4.3工作站,应用多平面重组(MPR)、容积再现(VR)、最大密度投影(MIP)、薄层滑块最大密度投影法(STS-MIP)及血管分析(VA)等进行处理。对正常组观察分析SMA空间解剖结构,包括其起始段走行、长度、分支及管径；测量SMA与腹主动脉(AA)夹角、左肾静脉(LRV)与十二指肠水平部(DHP)平面SMA与AA间距、LRV穿越SMA与AA之间的管径及LRV在左肾门最大管径；比较不同后处理方法对SMA及分支动脉的显示能力,包括对交通支的显示；以及在不同重建函数下观察图像质量的好坏。所有数据均使用SPSS13.0软件进行统计学分析。病变组：采用多种重建技术显示SMA,并分析SMA及其相关病变的特点。结果：SMA及其分布区域无病变影响的164例中,SMA走形及分布正常者140例(其中男性74例,女性66例,平均年龄52岁),SMA解剖变异者24例。140例正常组中MPR、VR、MIP、STS-MIP均清晰显示SMA的整体解剖形态结构,其中MPR矢状位图像直观显示SMA起始段及其与邻近AA、LRV等血管结构的解剖关系,SMA起始段走行呈转折型(A型)80例,径直型(B型)60例；正常组SMA与AA夹角为56.6°±24.1°,95%可信区间(52.6°-60.6°),LRV水平SMA与AA的距离为13.51mm±6.48mm,95%可信区间(12.42-14.59)mm；LRV穿越SMA与AA之间的管径为5.60mm±1.91mm,95%可信区间(5.28-5.92)mm；LRV在左侧肾门最大管径为9.97mm±1.47mm,95%可信区间为(9.73～10.22)mm；十二指肠水平部(DHP)平面SMA与AA间距为13.09mm±6.17mm,95%可信区间为(12.06～14.12)mm。正常组中A型夹角为72.9°±17.20,95%可信区间(69.1°-76.7°)；LRV水平SMA与AA的距离为17.39mm±5.99mm,95%可信区间(16.05-18.72)mm；LRV穿越SMA与AA时管径为6.22mm±1.90mm,95%可信区间(5.80-6.64)mm；LRV在左肾门最大管径为9.99mm±1.54mm,95%可信区间为(9.65-10.31)mm；DHP平面SMA与AA间距为15.57mm±6.24mm,95%可信区间为(14.18-16.96)mm。B型夹角为34.30±9.9°,95%可信区间(31.8°-36.90)；LRV水平SMA与AA的距离为8.43mm±2.57mm,95%可信区间(7.77-9.10)mm；LRV穿越SMA与AA时管径为4.74mm±1.55mm,95%可信区间(4.34～5.14)mm；LRV在左肾门最大管径为9.95mm±1.38mm,95%可信区间为(9.60-10.31)mm；DHP平面SMA与AA间距为10.19mm±5.10mm,95%可信区间为(8.87～11.51)mm。SMA与AA之间的夹角、间距均与SMA走行有关(P<0.05),与性别年龄无关(P>0.05)；LRV穿越SMA与AA之间的管径与SMA与AA之间的夹角有关(P<0.05),而LRV在左肾门的最大管径与SMA走行无关(P>0.05)。SMA分支较多,平均12支,大部分位于11～15支之间。在显示SMA及分支能力上,MPR、VR、MIP、STS-MIP对SMA主干及Ⅱ～Ⅲ级分支均无差异(p>0.05)；在显示Ⅳ～Ⅴ级以下血管时,MPR、STS-MIP与VR、MIP相比,差异有统计学意义(p<0.05),表明MPR、STS-MIP在显示细小血管上较VR、MIP具有优势。STS-MIP在显示SMA同周围血管及自身内部血管吻合支方面也具有优势。VA技术测量SMA长度19.8cm±2.2cm,LRV平面管径6.8mm±1.1mm,最小管径达1mm～2mm。不同函数重建,Stand、Soft、Detail三种方法获得的图像质量好,Bone函数图像差,不宜作腹部血管成像分析。24例SMA解剖变异主要表现为：SMA与腹腔干(CA)共干8例；肝总动脉(CHA)、肝右动脉(RHA)、肝左动脉(LHA)、脾动脉(SA)均起于SMA,共16例。48例病变组中,12例肠系膜上动脉缺血性病变,MPR像显示SMA管腔内软斑块及管腔狭窄,MIP显示管壁硬化斑块,VR直观显示SMA变窄或中断；6例肠系膜上动脉夹层,MPR、VR均见内膜瓣及双腔影；肠扭转及肠套叠12例,肠扭转轴位表现为肠系膜血管呈“漩涡征”,VR表现为SMA呈“螺旋状”走行,而肠套叠表现为“靶征”、“同心圆征”及“血管卷入征”；胡桃夹综合征(NCS)和肠系膜上动脉压迫综合征(SMACS)7例,其中4例胡桃夹患者SMA与AA夹角平均值为17.3°,LRV水平SMA与AA间距平均值为3.8mm,3例SMACS患者SMA与AA夹角平均为14.4°,DHP层面SMA与AA间距平均为5.8mm；消化道肿瘤11例,VR、STS-MIP均显示出SMA及分支与肿瘤血供关系。结论：64-SCTA是一种分辨率高、准确、快速、无创性的血管成像方法,多种后处理成像方法能清晰显示活体SMA的正常空间解剖形态结构及变异,能准确测量SMA与AA之间的夹角与间距；SMA解剖变异大,其中SMA径直走行时与AA之间的夹角与间距均较小,是导致SMA产生压迫性病变的潜在诱因之一。其次,64-SCTA对SMA及分支的显示能力较强,对显示SMA细小分支同周围组织之间的关系具有优势,特别是显示SMA与CA、IMA及自身分支血管内部之间的交通支,对判断侧枝循环建立具有重要意义。同时,64-SCTA对不同SMA病变影像特征的显示,有利于指导和帮助临床医师提高对SMA病变的诊断与认识,对评估病情的危重性与临床治疗方案的选择具有重要的实用价值。更多还原

【Abstract】 Objective:To investigate the normal imaging anatomy structure and viration of superior mesenteric arteries (SMA) by 64 spiral CT angiography(64-SCTA); and to evaluate the demonstrating ability in superior mesenteric arteries and to discuss the characteristics of image and clinical value of common diseases of SMA. Materials and Methods:164 patients with no associated disease involved SMA and its distributing region and 48 patients with associat-ed disease involved SMA and its distributing region underwent 64-SCTA scan, then the acquired original datas after being reconstructed by 0.625 slice thick were passed to ADW4.3 station to be postprocessed, adopting different methods including multiplanar reconstruction (MPR), volume rendering (VR), maximum intensity projection (MIP), sliding thin slab maximum vs minimum projection (STS-MIP), and vessel analaysis (VA). Normal set:To observe and analyze the three dimensional anatomy structure of SMA, including the origin segment path, total length, branch arteries and the diameter of SMA; To measure the angle between SMA and aorta (AA), the distance between SMA and AA in the plane of left renal vein (LRV) and duodenum horizontal part (DHP), the diameter of LRV going across SMA and AA,and the maximum diameter of LRV in the left kidney portal. To compare the demonstrating ability of SMA and its communi-cating arteries and observe the quality of image by various reconstructtion methods. All datas were analyzed by the SPSS13.0 software progress.In abnormal set:By various reconstruction techniques to demonstrate the SMA, and to analyze the characteristics of pathological and associated pathological in SMA. Results:Among 164 cases with no associated disease in SMA or its distribution region,140 cases is normal in the pathway and distribution region of SMA. Among the above 140 cases,74 cases is male,66 cases is female, and the average is 52 years old; The remained 24 cases exist anatomy variation. In normal set, the whole anatomy structure of SMA can be clearly demonstrated by MPR, VR, MIP and STS-MIP. MPR sagittal bits can directly display the anatomic relationship of original segment of SMA and the closed blood vessel, such as AA、LRV and so on. The pathway of origin segment of SMA presenting turn (A type) was 80 cases, and presenting striate (B type) was 60 cases; The angle between SMA and AA was 56.6°±24.1°,95% Confidence interval was (52.6°～60.6°). The distances between SMA and AA in plane of LRV were 13.51 mm±6.48 mm,95% Confidence interval was (12.42～14.59) mm; The diameters of LRV going across SMA and AA were 5.60mm±1.91mm,95% Confidence interval was (5.28～5.92)mm; The maximum diameters of LRV in the left kidney portal were 9.97 mm±1.47mm,95% Confidence interval was (9.73～10.22)mm; The average distances between SMA and AA in plane of DHP were 13.09mm±6.17mm,95% Confidence interval was (12.06～14.12) mm. In normal set, the angle between SMA and AA in type A was 72.9°±17.2°, 95% Confidence interval was (69.1°～76.7°). The distances between SMA and AA in plane of LRV were 17.39mm±5.99mm,95% Confidence interval was (16.1～18.7)mm. The diameters of LRV going across SMA and AA were 6.22 mm±1.90mm,95% Confidence interval was (5.80～6.64)mm.The maximum diameters of LRV in the left kidney portal were 9.99mm±1.54mm,95% Confi-dence interval was (9.65～10.31)mm.The distances between SMA and AA in plane of DHP were 15.57mm±6.24mm,95% Confidence interval was (14.18～16.96)mm. The angle between SMA and AA in type B was 34.3°±9.9°,95% Confidence interval was (31.8°～36.9°). The distances between SMA and AA in plane of LRV were 8.43mm±2.57mm,95% Confidence interval was (7.77～9.10)mm. The diameters of LRV going across SMA and AA were 4.74mm±1.55 mm,95% Confidence interval was (4.34～5.14)mm. The maximum diameters of LRV in the left kidney portal were 9.95mm±1.38mm,95% Confidence interval was (9.60～10.31)mm. The distances between SMA and AA in plane of DHP were 10.19mm±5.10mm,95% Confidence interval was (8.87～11.51)mm. The angel and distance between SMA and AA was related to the pathway of SMA(P<0.05),but not related to sex or age (p>0.05). The diameter of LRV going across SMA and AA was related to the angle between them, but the maxium diameters of LRV in the left kidney portal is not related to the pathway of SMA (p>0.05). SMA has many branches,the number of which varies from 11 to 15, and the average is 12. Comparing the ability of demonstrating SMA and its branch arteries, there was no statistical meaning (p> 0.05) in demonstrateing the major branch andⅡ～Ⅲlevel branch arteries of SMA by MPR, VR, MIP and STS-MIP, and there was statistical meaning (p<0.05) in demonstratingⅣ～Ⅴlevel branch arteries comparing MPR and STS-MIP to VR and MIP, meaning MPR and STS-MIP have advantage over VR, MIP in demonstrating tiny vessel. STS-MIP also has special advantage in displaying the net of vessel in SMA or around it. Amonge the different reconstruction, the image of Stand、Soft and Detail is better, but the image of Bone is unwell and can’t to make analysis in vessel of abdomen. The length of SMA was 19.8cm±2.2cm, the diameter was 6.8mm±1.1mm in plane of LRV, and the minimum diameter of SMA can reach to 1mm～2mm with VA technology. Among 24 cases which exists anatomy varition, SMA and celiac trunk derive from the same vessel (n=8); Common hepatic artery, Right hepatic artery, Left hepatic artery and Splenic artery derive from SMA (n=16). Among the abnormal cases of 48, SMA ischemic changes (n=12), MPR display the soft patch in the lumen and narrow of SMA, MIP display sclerosis plaque in the vessel wall,VR display the narrow or discontinue of SMA;The dissection of SMA (n=6), MPR and VR can display the inner membrane and double cavity image; The intestine volvulus and Intestinal intussusception (n=12), On axial images of the intestine volvulus, the "whirlpool" sign of mesentery vessels were showed, The VR display "whirlpool" of SMA But intussusception showed target sign or cocentric circle sign and blood vessels curling sign. NCS and SMACS (n=7), Among them,4 cases of NCS the average angel between SMA and AA was 17.3°, the distance between SMA and AA in the plane of LRV was 3.8mm.3 cases of SMACS, the average angel between SMA and AA was 14.4°, the distance between SMA and AA in the plane of DHP was 5.8mm. The gastronintestinal tumor (n=11), VR and STS-MIP all displayed the blood supplying relationship between SMA and its branch arteries in tumor. Conclusion:64-SCTA is a high resolution, accurate, fastspeed and noninassive angiograpy method, and its various postprocessing methods can clearly demonstrate the normal three dimensional anatomy structure and variation of SMA, It can accurately measure the angle and distance between SMA and AA; The spacial anatomy in organism exists obvious variation, especially when SMA goes striate, the angle between SMA and AA becomes smaller, which is a potential agent in causing SMA compressing diseases. Furthermore,64-SCTA has a better demonstrating ability for SMA and its branch arteries, making it suitable to observe the relation between the tiny branches of vessel and surrounding tissue. Especially it has obvious advantage when display SMA, CA, IMA and the communicating branches vessel among themselves,which matters much to assese the esistence of collateral circulation. At the same time,64-SCTA can characteristically display various diseases of SMA, and making it suitable to guide and help clinical docters to improve the diagnosis and knowledge, which it has important value to assess the dangeriousity of patients condition and to choose clinical scheme.更多还原