CT MRI 最终打印 小抄版

1、束腰征：垂体大腺瘤向鞍上生长，冠状面呈葫芦状，是因鞍隔束缚肿瘤所致。直角脱髓鞘征：多发性硬化横断面病灶呈圆形或椭圆形，冠、矢状面呈条状，可垂直于侧脑室。白靶征：脑囊虫死亡后，在t2wi上囊肿内囊液及周围水肿呈高信号，而囊壁与囊内模糊不清的头结呈低号。肾血管平滑肌脂肪瘤：又名错构瘤，是肾脏较为常见的良性肿瘤，由不同比例的血管、平滑肌和脂肪组织构成。一般肿瘤为孤立性。窗宽：指显示图像时所选用某一定范围的ct值，使只有在规定范围内的不同ct值，才能有灰度的变化，而在此范围最低值和最高值以外的ct值，一律分别显示为黑或白色。黑靶征：脑囊虫的病人在tiwi可见多个散在的小圆形囊性病灶，表现为低信号，部分

2、病灶在tiwi上黑色的低信号内可见到点状高信号。小肝癌：直径3cm的单发结节，或2个结节直径和不超过3cm的肝细胞癌为小肝癌。小脑扁桃体下疝 ： 为常见的先天性发育异常。是由于胚胎发育异常使小脑扁桃体下部下降至枕骨大孔以下、颈椎管内，严重者部分延髓下段、四脑室下部蚓部也下疝入椎管内。常合并有脊髓空洞。 ct值：系ct扫描中x线衰减系数的单位，用于表示ct图像中物质组织线性衰减系数(吸收系数)的相对值。用亨氏单位(hounsfield unit)表示，简写为hu。部分容积效应：c t图像上各个像素的数值代表相应单位组织全体的平ct值，它不能如实反映该单位内各种组织本身的ct值 ，在扫描过程中，凡

3、小于层厚的病变，其ct值受层面内 其他组织的影响，所测得的ct值不能代表病变的真正的ct值的现象。 三、填空题1、脑转移瘤的特点：小病灶、大水肿、多发生、呈环形强化。2、脑挫裂伤包括脑挫伤和脑裂伤；可同时累及灰白质。3、空洞的分类：虫蚀样空洞、薄壁空洞和厚壁空洞。4、胸腔积液包括游离性胸腔积液、包裹性胸腔积液和叶间积液。5、横隔附近胸腔积液与腹水的鉴别：横隔征、隔角移位征、界面征、裸区征。6、支气管扩张ct表现包括：囊状支气管扩张、柱状支气管扩张和静脉曲张型支气管扩张；三大临床症状咳嗽、咳痰和咯血。7、肺隔离症螺旋ct动态增强检查可显示肺隔离症来自体循环的供养动脉。8、原发性胸膜肿瘤主要是间皮

4、瘤和纤维性肿瘤，继发性主要是转移性肿瘤。9、肝癌的分为巨块型肝癌、结节型肝癌和弥漫型肝癌。10、胆石症ct检查胆结石可分为高密度(ct值25hu)、等密度（ct值0-25hu）、低密度（ct值0hu）11、通常脾脏外缘超过5个肋单位，提示有脾肿大。12、脾破裂根据破裂程度可分为完全性破裂、中央破裂和包膜下破裂。13、脾外伤ct表现：脾包膜下血肿、脾撕裂和脾实质内血肿。14、融合肾：马蹄肾（horse-shoe kidney）最常见，以下极融合多见。融合部称为峡部，多为肾实质，少数为纤维组织 。15 急性期出血呈等t1短t2信号，亚急性早期出血呈短t1长t2信号，含铁血黄素环呈长t1_短t2信号

5、。16 脂肪呈 短 t1 长t2信号，自由水呈长t1长t2信号，钙化多呈长t1短t2信号四、简答题1、简述肝细胞癌的ct表现？平扫示肝硬化表现，肝轮廓局限性突起，肝实质内出现单发或多发、圆形或类圆形边界清楚或模糊的低密度肿块，周围可见更低密度的线状影为肿瘤假包膜对比增强扫描，动脉期正常肝实质尚未出现对比增强，而肿瘤很快出现明显的斑片状、结节状强化，门静脉期正常肝实质密度开始升高而肿瘤密度迅速下降，平衡期肿块对比增强密度继续下降，而在明显强化肝实质的对比下又表现为低密度，整个过程呈“快进快出”征象胆道系统受侵犯引起胆道扩张肝门部或腹主动脉旁、腔静脉旁淋巴结增大提示淋巴结转移cta示邻近血管受压移

6、位，肿瘤内出现病理血管及门、腔静脉内出现的充盈缺损2、如何鉴别周围型肺癌和结核瘤？主要从肿瘤的密度、边缘、周围征象以及增强扫描等几个方面鉴别：肺癌肿块直径可在110cm的范围，而结核球直径多为23cm，少数在4cm以上；肺癌发生在任何部位，而结核球在上叶尖后段和下叶背段多见；肺癌密度多较均匀，内部可见空泡征，少有钙化；结核球密度较高，可见块状或斑片状钙化；肺癌边缘分叶及细小毛刺多见，而结核球边缘多光滑，无深分叶；肺癌多见胸膜凹陷征，有的肿瘤周围可见血管纠集征，而结核球常有卫星灶；增强扫描肺癌强化较明显，而结核球多无明显强化或仅有包膜强化。3、急性胰腺炎的ct表现？急性水肿性胰腺炎，ct可无阳性

7、表现。多数病例均有不同程度的胰腺体积弥漫性增大。胰腺密度正常或为均匀、不均匀轻度下降。胰腺轮廓清晰或模糊，渗出明显者除胰腺轮廓模糊外，还可有胰周积液。增强ct扫描，胰腺均匀强化，无不强化的坏死区。急性坏死性胰腺炎，1胰腺体积常有明显增大，且为弥漫性。2胰腺水肿则ct值降低，坏死区的ct值更低，而出血区的ct值明显增高，整个胰腺密度显得很不均匀。增强扫描坏死区无强化而对比更明显。3胰腺周围的脂肪间隙消失，胰腺边界由于炎性渗出而变得模糊不清。4胰周往往出现明显积液，常首先累及左侧千盛旁间隙，肾筋膜可因炎症而增厚。4、星型细胞瘤的mri表现？i级星形细胞瘤： mri表现tiwi肿瘤呈低信号或等信号，

8、t2wi 上为高信号，增强扫描肿瘤轻度强化或无强化。级星形细胞瘤：mri 肿瘤tiwt呈等、低信号t2wi为高信号，增强扫描可部分强化。级星形细胞瘤： mri表现为tiwi、t2wi病灶均为边界不清的混杂信号，增强扫描肿瘤呈不均匀明显强化。级星形细胞痛： mrt检查 tiwi及t2wi均为混杂信号，囊变坏死区在t2wi上呈高信号，增强扫描后呈厚壁环状强化或团块状强化。5、硬膜下血肿与硬膜外血肿的鉴别诊断？a.形态：新月形，月牙形；梭形，双凸镜形，内缘境界清楚。b.分布范围：广，可越过颅缝；较窄，不越过颅缝。c.伴发蛛网膜下腔出血：常见；较少见。d.占位效应：明显；范围大者较明显6、椎管内肿瘤起

9、源部位的鉴别要点？mri表现：（1）髓内肿瘤：脊髓局限性增粗。病灶周围蛛网膜下腔变窄或闭塞。（2）髓外硬膜内肿瘤：病灶较局限，边缘光滑清楚；脊髓受压变形，并向对侧移位。肿瘤侧蛛网膜下腔增宽，而肿瘤对侧蛛网膜下腔变窄。（3）髓外硬膜外肿瘤：硬膜外肿块形态常不规则，呈上下径较长的扁平形肿块向内压迫脊膜囊，造成邻近蛛网膜下腔的变窄，脊髓受压向对侧移位7、颅内非病理性钙化包括哪些？松果体钙化，10岁前少见，成人40%显影 大脑镰钙化 床突间韧带钙化（桥形蝶鞍） 侧脑室脉络丛钙化 其他：基底节区、小脑齿状核、岩床韧带8、脑膜瘤的mri表现?（一）通常在t1wi上的信号与邻近脑组织的脑皮质相似，常为等信号

10、，而与脑白质比较为低信号。在t2wi上为等信号掩盖。就信号而言，绝大多数其他颅内肿瘤呈长t1长t2信号，脑膜瘤上述信号特点有一定特征性。（二）增强后脑膜瘤有显著而均匀的增强，脑膜瘤附着处的脑膜受肿瘤浸润有显著增强，叫“硬膜鼠尾征”（或“脑膜尾征”）有特征性。（三）部分病变被移位了的脑脊液信号或血管流空信号包绕，似假包膜，构成了脑膜瘤特征性表现。9、子宫肌瘤ct表现及分型？各型肌瘤的ct表现包括如下：1、黏膜下肌瘤黏膜下肌瘤ct表现为子宫增大，宫腔变小，增大的宫腔可见类圆形与子宫密度大致相当的肿块，增强扫描肿块显著均匀强化，边缘可见“假包膜”。但ct平扫不易与子宫肥大症、子宫体癌、子宫腺肌症区别

11、，增强扫描有助于诊断。2、浆膜下肌瘤ct表现为宫外肿块，边缘清晰，由于血供较差，大多数平扫呈混杂密度，中性变性、坏死部分呈低密度。当肿块的基底与子宫相连，浆膜下子宫肌瘤与肌壁间肌瘤的ct表现类似。当浆膜下肌瘤ct表现为宫外实质肿块时，应注意与卵巢恶性肿瘤、卵巢子宫内膜异位囊肿相鉴别。3、肌壁间肌瘤肌壁间肌瘤常使子宫不均匀增大及轮廓变形，局限性隆突，宫腔变小。由于大多数肌壁间肌瘤使子宫轮廓改变，平扫不易漏诊。增强扫描后肌瘤显著均匀强化或不均匀强化，其内可见漩涡状、小斑片状低密度，周边可见“假包膜”，此类肌瘤应注意与子宫腺肌病、子宫体癌鉴别。10、简述肺结核、肺癌及肺脓肿的空洞表现？原发性支气管肺

12、癌空洞特点-肿瘤供血不足（d3mm）,导致肿瘤缺血坏死液化 鳞癌多见瘤周可见胸膜凹陷征、血管集束征、瘤体内偶见斑点样及砂粒样钙化。洞壁厚薄不一, 凹凸不平, 有癌结节, 周围可见淋巴转移、胸膜转移。肺结核空洞的特点:-干酪样坏死伴周围纤维组织增生结核空洞多位于两上叶尖后段和下叶背段, 常单发, 有弧形、环形或弥漫点状钙化及卫星灶, 并可见周侧或对侧肺内播散灶,结核性空洞是在肺结核基础上形成的, 当结核干酪坏死液化并与外界空气相通则形成结核空洞, 可表现为厚、薄及无壁空洞, 气液平少见, 但原发性结核中有气液平的大空洞。肺脓肿空洞的特点:肺脓肿洞周常伴浓密炎性病变, 洞内可见中等量以上液平。急性

13、肺脓肿外壁常界限不清, 周围大片实变影, 其内壁凹凸不平, 可见气液平面。慢性肺脓肿内、外壁界限均较清楚, 洞壁较厚, 邻近肺野可显示慢性炎症、支扩、新的播散灶和旧的纤维化等。血源性感染常呈散在粟粒状、结节状或球状, 不规则肿块样阴影, 其内可见液化、坏死及空洞, 常合并脓胸。11、简述胰腺癌的ct表现？平扫肿瘤密度与胰腺相等或略低，病灶出现坏死或液化形成低密度区。因胰腺癌是乏血供肿瘤，增强扫描时肿块强化不明显，呈相对低密度。胰管、胆管扩张呈“双管征”为胰头癌常见征象，可伴有胰体尾萎缩或引起远端潴留性假性囊肿。胰头癌进一步发展可使胰周脂肪层消失，邻近血管被推移或侵犯，表现为被包埋、不规则狭窄或

14、闭塞。胰周、腹膜后、肝门淋巴结和肝内出现转移。五、论述题mri在中枢神经系统病变中较ct的优势？组织分辨率高（灰白质、髓鞘形成状态及病理改变敏感性高）成像序列多（参数可任意调节，及辅助方法如脂肪抑制、水抑制、 磁化传递技术）三维成像、直接采集对比增强（正开发组织/器官特意性对比剂）血管成像流动测量（提供脑脊液、血液的非形态学信息，并定量分析）介入导向mri在中枢神经系统应用较为成熟。多方位和三维成像的应用使病变定位诊断更为准确，借助流空效应还可观察病变与邻近血管的关系。对脑干、幕下区、枕骨大孔区、脊髓与椎间盘病变的显示要优于ct。对脑脱髓鞘疾病、脑梗死、脑与脊髓的肿瘤、血肿、脊髓先天异常与脊髓

15、空洞症的诊断也有很高价值。mra对脑血管的主干及主要分支的疾病具有很高的筛选作用。mr功能成像的信息对疾病的诊断也有很大帮助winger tuivasa-sheck, who scored two tries in the kiwis 20-18 semi-final win over england, has been passed fit after a lower-leg injury, while slater has been named at full-back but is still recovering from a knee injury aggravated agains

16、t usa.both sides boast 100% records heading into the encounter but australia have not conceded a try since josh charnleys effort in their first pool match against england on the opening day.aussie winger jarryd hayne is the competitions top try scorer with nine, closely followed by tuivasa-sheck wit

17、h eight.but it is recently named rugby league international federation player of the year sonny bill williams who has attracted the most interest in the tournament so far.the kiwi - with a tournament high 17 offloads - has the chance of becoming the first player to win the world cup in both rugby le

18、ague and rugby union after triumphing with the all blacks in 2011.id give every award back in a heartbeat just to get across the line this weekend, said williams.the (lack of) air up there watch mcayman islands-based webb, the head of fifas anti-racism taskforce, is in london for the football associ

19、ations 150th anniversary celebrations and will attend citys premier league match at chelsea on sunday.i am going to be at the match tomorrow and i have asked to meet yaya toure, he told bbc sport.for me its about how he felt and i would like to speak to him first to find out what his experience was.

20、uefa hasopened disciplinary proceedings against cskafor the racist behaviour of their fans duringcitys 2-1 win.michel platini, president of european footballs governing body, has also ordered an immediate investigation into the referees actions.cska said they were surprised and disappointed by toure

21、s complaint. in a statement the russian side added: we found no racist insults from fans of cska. baumgartner the disappointing news: mission aborted.the supersonic descent could happen as early as sunda.the weather plays an important role in this mission. starting at the ground, conditions have to

22、be very calm - winds less than 2 mph, with no precipitation or humidity and limited cloud cover. the balloon, with capsule attached, will move through the lower level of the atmosphere (the troposphere) where our day-to-day weather lives. it will climb higher than the tip of mount everest (5.5 miles

23、/8.85 kilometers), drifting even higher than the cruising altitude of commercial airliners (5.6 miles/9.17 kilometers) and into the stratosphere. as he crosses the boundary layer (called the tropopause),e can expect a lot of turbulence.the balloon will slowly drift to the edge of space at 120,000 fe

24、et ( then, i would assume, he will slowly step out onto something resembling an olympic diving platform.they blew it in 2008 when they got caught cold in the final and they will not make the same mistake against the kiwis in manchester.five years ago they cruised through to the final and so far hist

25、ory has repeated itself here - the last try they conceded was scored by englands josh charnley in the opening game of the tournament.that could be classed as a weakness, a team under-cooked - but i have been impressed by the kangaroos focus in their games since then.they have been concentrating on the sort o