1、腹部横断层解剖,From ,Abdomen Sectional Atlas: 1,The following cross-sectional atlas of a normal male abdomen demonstrates anatomical relationships of the abdominal organs in the context of the CT scan. The sections span the area between the dome of the right hemidiaphragm at T9 to L5 below the aortic bifur
2、cation.,Abdomen Sectional Atlas: 2,The air-filled colon outlines a pendent transverse colon between prominent hepatic and splenic flexures. Note the proximity of the heart to the cardia of the stomach and the lesser curve of the stomach crossing the T12-L1 disc.,Abdomen Sectional Atlas: 3,The sequen
3、ce of abdomen sections 1 to 14 below, shown as an animation.,Abdomen Sectional Atlas: 4,The section levels superimposed on an x-ray. Click the appropriate number above to view a particular section.,1 2 3 4 5 6 7 8 9 10 11 12 13 14,Abdomen Sectional Atlas: section 1,By convention, CT cross sections a
4、re viewed from a caudal perspective. Section 1, at the level of T9, cuts across the dome of the right hemidiaphragm, the bases of the lungs, and the long axis of the ventricles of the heart. The termination if the inferior vena cava is seen at its junction with the right atrium (see Heart Anatomy, C
5、ross-Sections).,Abdomen Sectional Atlas: section 2,The second section, through T10, sections the dome of the liver where faint traces of the hepatic veins can be seen converging toward the hepatic portion of the inferior vena cava (see Right Upper Quadrant Anatomy). The aorta is still to the left of
6、 the midline in the lower posterior mediastinum and the esophagus lies directly anterior to it. When exploring an abdomen with no nasogastric tube in place, the aortic pulsation is the guide to the location of the esophagus.,Abdomen Sectional Atlas: section 3,Level 3, at the top of T11, starts to ca
7、tch the cardia of the stomach and the adjacent upper pole of the spleen. Note the esophagus anterior to the aorta, indicating this section is above the esophago-gastric junction.,Abdomen Sectional Atlas: section 4,At the bottom of T11, the portal vein is seen in the hepatic hilum. The esophago-gastr
8、ic junction is seen. The body of the spleen is partially separated from the body of the stomach by the prominent splenic flexure in this individual (see Spleen Anatomy).,Abdomen Sectional Atlas: section 5,At the middle of T12, the body of the gallbladder is seen as a radial lucency within the liver.
9、 The plane through the gallbladder bed and the inferior vena cava divides the liver into right and left lobes (see Hepatic Anatomy, Caudal View). The crura of the diaphragm are seen uniting anterior to the aorta as the arcuate ligament. The posteromedial border of the spleen is indented by the begin
10、ning of perinephric fat within Gerotas fascia. The hilum and gastric surface of the spleen faces anteromedial.,Abdomen Sectional Atlas: section 6,At the upper border of L1, the celiac trunk emerges perpendicular to the aorta, just beneath the arcuate ligament of the crura (see image abdG3004). The p
11、ancreas is draped across the origin of the celiac and the tail of the pancreas abuts the hilum of the spleen (see image panG3001). The upper pole of the left kidney and adjacent adrenal gland are seen. The top of the right adrenal gland is seen immediately posterior to the inferior vena cava where t
12、he adrenal vein drains directly into its posterior wall.,Abdomen Sectional Atlas: section 7,At the bottom of L1, the superior mesenteric artery arises from the aorta. Immediately anterior to it, the celiac is dipping down to divide into splenic and hepatic branches. Just anterior to the celiac, the
13、splenic vein is seen as a light streak along the posterior border of the pancreas. The splenic vein drains into the portal vein posterior to the neck of the pancreas (see Portal Vein anatomy). The lower pole of the spleen abuts the middle of the left kidney.,Abdomen Sectional Atlas: section 8,At the
14、 level of L2, the superior mesenteric artery and vein are distinctly seen in the root of the small bowel mesentery. The third portion of the duodenum passes between them and the great vessels (see panG3001). The left renal vein crosses the aorta to drain into the inferior vena cava. Note the short r
15、ight renal vein. Branches of the renal arteries, which arose anterolaterally just below the level of the superior mesenteric, are seen entering the renal hila.,Abdomen Sectional Atlas: section 9,At the top of L3, the tip of the right hepatic lobe is seen as well as the left renal pelvis.,Abdomen Sec
16、tional Atlas: section 10,At the lower portion of L3, the inferior mesenteric artery is seen arising from the aorta (see Lower GI Bleed Case Study). The left ureter is visualized lying at the anterior border of the left psoas muscle. The draped transverse colon occupies the anterior abdominal space.,
17、Abdomen Sectional Atlas: section 11,Near the top of L4, the lower poles of the kidneys are seen as well as the numerous vessels in the small bowel mesentery. The lucency around the kidneys is perinephric fat, which tapers above and below the kidneys within Gerotas fascia (see image bilL3018).,Abdome
18、n Sectional Atlas: section 12,At L4, the aortic bifurcation is seen. The narrow descending colon on the left and wide cecum on the right are seen. The appendix is visualized with contrast in the lumen (see Appendectomy). The appendix is retrocecal here as it is in the majority of individuals.,Abdome
19、n Sectional Atlas: section 13,At the top of L5, the common iliac arteries diverge. The base of the appendix is seen at the cecum. Note the umbilicus in relation to the aortic bifurcation.,Abdomen Sectional Atlas: section 14,At the lower portion of L5 near the lumbosacral junction, the psoas muscles
20、have become larger and rounded as they begin their anterior course around the brim of the true pelvis (see image abdG3004).,Abdomen Sectional Reconstructions: 1,Stacking the sections allows conceptual reconstruction and visualization of relationships (see image abdG3005).,Abdomen Sectional Reconstru
21、ctions: 2,The high posterior position of the spleen beneath the left hemidiaphragm affords protection by the rib cage (and makes it difficult to reach by laparotomy). Note the relationships to cardia of stomach, left kidney and splenic flexure of colon (see Spleen Anatomy).,Abdomen Sectional Reconst
22、ructions: 3,The kidneys lie in the retroperitoneum surrounded by perinephric fat, encapsulated within the anterior and posterior lamina of Gerotas fascia. The fusiform psoas muscles direct the axis of the kidneys anterolaterally toward the lower poles. Note relationships to surrounding structures (s
23、ee images abdG3004 and abdG3005).,Abdomen Sectional Reconstructions: 4,The liver fills the right hemidiaphragm and extends to the left between the heart and cardia of the stomach anteriorly (see image abdG3005, biliary-hepatic anatomy). Note the relationship to the right kidney, hepatic flexure of colon and duodenum, all of which make impressions on the underside of the liver (see Hepatic Anatomy, Caudal View).,
