Blood vessels the aorta and its branches,

Abdominal Ultrasound:Step by StepBerthold Block, MDPrivate PracticeBraunschweigGermany

2nd edition

912 Illustrations

ThiemeStuttgart · New York

Table of Contents

3 Blood Vessels: The Aorta and its Branches,

1. The Vena Cava and its Tributaries . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2. Organ Boundaries . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 193. Locating the aorta and vena cava . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4. Demonstrating the aorta and vena cava in their entirety . . . . . . . . . . . . 5. Organ Details . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6. Demonstrating arterial and venous pulsations . . . . . . . . . . . . . . . . . . . . . . 7. Evaluating the vessel walls and lumina . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8. Identifying and defining the branches of the aorta and vena cava . . . . 9. Anatomical Relationships . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10. Relationship of the aorta and vena cava to the diaphragm, liver, and cardia . . . . . . . . . . .11. Area surrounding the celiac trunk and the course of the hepatic artery, splenic artery, and

left gastric artery . . . . . . . . . . . . 12. Superior mesenteric artery, splenic vein, and renal vessels . . . . . . . 13. Iliac vessels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14. Lymph nodes near the retroperitoneal vessels . . . . . . . . . . . . . . . . . . . .

Fig. 3.1Barriers to scanning the aorta (A) and vena cava (Vc).The transverse colon (Ct) is a barrier to scanning, along with the antrum (An) and duodenum (Du). Ri = costal arch.

Upper abdominal transverse scanof the aorta and vena cava.Aorta (↑), vena cava (↑ ↑).

Transverse scan at the level of thebifurcation. Aortic bifurcation (↓↓),vena cava (↑).

Transverse scan just above theumbilicus. Details are obscuredby gas in the transverse colon.

Transverse scan between theumbilicus and xiphoid. Aorta (↑),vena cava (↑ ↑).

Longitudinal scan of the aorta (↑)demonstrating the entry of theaorta into the thoracic cavity.

The transducer was moved to theright. This scan cuts the spacebetween the aorta and vena cava.

The transducer was moved fartherto the right, defining the vena cavain longitudinal section (↑).

Longitudinal scan of the aorta (↑).

The transducer was moved to theright. This scan cuts the spacebetween the aorta and vena cava.

The transducer was moved fartherto the right, showing a longitudinalsection of the vena cava (↑).

Diagram showing the plane of thetransverse scan (b) and the planesof the longitudinal scans (c, d).

Upper abdominal transverse scan.Aorta kinked to the left (↓), venacava (↑).

Longitudinal scan. A gap (↑) is visiblebelow the superior mesenteric artery(↓ ↓).

The transducer was moved caudad,demonstrating the continuation ofthe aorta and a posterior kink in thevessel (↓).

Image the aorta in longitudinal section. Look at its thick, echogenic wall. Occasionallya typical three-layered wall structure can be seen (Fig. 3.7). Notehow the size of its lumen does not change during pulsations or during inspiration/expiration. Apply pressure over the aorta with the transducer and noticethat it is not compressible. The normal aorta tapers from above downward,its diameter decreasing from approximately 2.5 cm to 2.0 cm.Define the vena cava in longitudinal section. Notice its thin wall and thechanges in its caliber during the pulse phases. Have the subject breathe inand out (Figs. 3.8, 3.9) and observe how the lumen narrows during inspiration.

Longitudinal scan of the aorta.The three-layered wall structure is faintlyvisible (↑). Notice the smooth outline ofthe vessel wall. Fig. 3.8 Longitudinal scan of the

vena cava during inspiration (↑).Fig. 3.9 Vena cava duringexpiration (↓).

Aortic aneurysms tend to enlarge over time. The larger the aneurysm, the more rapid its progression. Aneurysms less than 5 cm in diameter grow by 2–4mm each year. Cases of this kind should be scanned every three monthsto evaluate size. Aneurysms with a diameter of 5 cm or more grow by up to 6mm per year. These cases should be evaluated for surgical treatment. With aneurysms larger than 7 cm, the risk of rupture in one year is greater than50%.

Position the transducer for an upper abdominal transverse scan and identifythe liver, which at this level is interposed between the aorta and vena cava.The cardioesophageal junction lies anterior to the aorta. The hypoechoic musculature of the diaphragm is also seen (Fig. 3.26a). Rotate the transducer to a longitudinal plane and scan through the region. Identify the vena cava(Fig. 3.26b), the caudate lobe of the liver (Fig. 3.26c), the aorta, and the gastric cardia lying anterior to it (Fig. 3.26d). (The caudate lobe is described in detail on p. 67ff. and the gastroesophageal junction on p.166ff.)

The End

Muhammad Kashif AnwarM.Sc , RDCS, RCS

kashifanwer@mail.com