1、胸部正常CT解剖,目 录,概论 纵隔窗的CT解剖 肺窗的CT解剖,前 言肺、纵隔内部组织结构之间、正常结构与病变之间的密度差异CT满意显示胸部正常结构和病灶的大体解剖，定位、定量准确，为定性分析提供形态学基础,有关胸部CT检查技术的几个问题 1、CT值与窗宽、窗位：肺窗和纵膈窗，双 窗技术 2、层厚和层距：吸气末扫描，薄层/重叠扫描；减小部分容积效应、肺血坠积现象 3、平扫和增强扫描：LN，病灶，血管 4、高分辨CT（High Resolution ,HRCT） 层厚 12mm，显示次级肺小叶结构；显示间质性病变、支扩、孤立小病灶,胸部正常CT解剖,纵隔窗,一、 主要观察内容 1、纵膈：有无纵
2、膈肿块、多余结构LN有无肿大或/及增多 “三管”结构形态（气道结合肺窗）2、较大范围的肺、胸膜（腔）病变的内部结构3、阅片顺序： 辨认每一层纵膈内的“三管”结构自上而下、由近段向远段完整观察某一结构,主要层面和结构,主动脉弓及其以上层面：辨认头臂血管 主-肺动脉窗层面：窗空虚/潜在，气管分叉，奇V弓 右上叶支气管层面：左PA弓、右上PV前干，右上PA，上腔V 左上叶支气管层面：右中间段支气管，右PA，右下PA，左上PV，左PA降支 其他肺门层面：两侧大小基本对称（肺窗显示更佳），相伴随的支气管和PA分支，由近向远渐小,Can you find the right and left subcla
3、vian arteries? (click for answer),The right subclavian artery as it dumps into the brachiocephalic artery. (click to highlight),What are the 3 yellow air-filled (black) structures highlighted here? (click to highlight),This is contrast (white) being injected into the left subclavian vein.,Can you fi
4、nd the first 3 branches off the aortic arch? (click for answer),Incidental lipoma (fat tumor) (notice it is the same density as fat in the chest wall),Can you find the left brachiocephalic vein as it dumps into the SVC? (click for answer),We are at the level of the top of the aortic arch (click to h
5、ighlight),Can you find the right pectoralis major and minor? (click for answer),What is the structure in blue? (click to highlight),This is the Superior Vena cava,Can you find the azygous arch ? (where the azygous vein comes across to dump into the SVC) (click for answer),Notice the bifurcation of t
6、he trachea (corina) at this level (click to highlight),What is the structure in red? (click to highlight),This is the left pulmonary artery.,Can you find the pulmonary trunk and right pulmonary artery? (click for answer),Where are the ascending (A) and descending (D) limbs of the thoracic aorta? (cl
7、ick to highlight),We are at the level of the top of the left atrium. Notice The pulmonary veins dumping into it as they return from the lungs. (click to highlight),Can you find the left main coronary artery coming off the aorta? (click for answer),You can further see The left coronary branch into th
8、e Circumflex artery and the LAD artery (click to highlight),Here is a good image of the aortic semi-lunar valve leaflets. Can you find them? (click for answer),Here is a good image of the left atrium dumping Into the left ventricle. Can you find it? (click to highlight),You can clearly see the left
9、ventricular wall and septum with the projecting papillary wall muscles attaching to the mitral valve leaflets. (click to highlight),Contrast filling the right ventricle,Can you find the pericardial sac here? (click for answer),It is relatively easy to see because there is a fat layer around the hear
10、t and around the pericardium making the soft tissue more visible,纵膈的分区方法：CT较平片（侧位）直接显示 前纵膈 - 心脏、大血管前间隙，胸腺 中纵膈 - “三管”结构及其周围间隙、LN 后纵膈 - 脊柱旁（沟）；脊神经、植物神经 心脏和心包,胸部正常CT解剖,肺窗,一、主要观察内容1、CT肺门（肺野内带）：第一、二肺门之间的血 管、支气管等内侧 - 与纵膈内支气管、血管相续（结合纵膈窗）外侧 - 段支气管开口处，与外周支气管血管束相续2、支气管血管束（肺野中带）由肺门发出的、相伴行的支气管和肺A分支；向肺门/左房回流的、无支
11、气管伴行的肺静脉 3、外周肺（胸膜下区）：段以下的血管、支气管断面 影，呈小条、星、叉、点状 4、阅片要点：抓住重点层面，观察每一层时，注意上下相邻层面，完整观察某一结构,二、主要层面和结构 标志：与肺门相续的支气管、血管1、右上叶支气管以上层面： 两侧尖段支气管及其外侧的同名动脉 2、右上叶支气管层面：右主支气管，前、后段支气管， 右PA上干；右上PV前干左上前段支气管3、右中间段支气管层面：叶间动脉（右下PA 干）4、左上叶支气管层面：左主、左上叶支气管5、右中叶、左舌叶，两侧下叶背段气管开口层面： 中叶脊，左下肺A 以下层面：基底段支气管和PA分支，两侧基本对称；近水平走向的双下PV，由近向远渐小 几个注意点：,肺叶、肺段的判断 肺门邻近-叶、段支气管外周肺-叶间胸膜（裂）细线状稍高密度带状乏血管带（区）,
