Ultrasound Aorta

Aorta

Ultrasound is an effective and convenient way to confirm or exclude an abdominal aortic aneurysm (fig. 45).
Dimensions of the abdominal aorta: 

• Normal < 2.5 cm
• Dilatation > 2.5 cm 
• Aneurysm > 3 cm 

In the event of abdominal aortic aneurysm, a CTA examination may be performed for additional evaluation.

Intestines

Appendicitis

We are frequently asked to confirm or exclude appendicitis in patients with abdominal pain. The appendix is located in the right lower abdomen, usually has a diameter of less than 7 mm and is compressible. When the appendix is infected, the diameter will increase and the appendix will no longer be compressible. There will also be fatty infiltration around the inflamed appendix and increased flow will be visible around the appendix using color Doppler. There may also be a trace of free fluid (fig. 46)

At times an echogenic structure with acoustic shadowing may be found in the appendix lumen secondary to appendicitis; the appendicolith (fig. 47). The etiology of this calcified structure has not been elucidated yet. It is thought that an appendicolith obstructs outflow, enabling bacteria to replicate and cause infection

Thickened intestinal wall 

Full and reliable evaluation of the entire small intestine is never possible. But in most cases the terminal ileum can be evaluated, which is important when confirming or excluding Crohn's disease (fig. 48).

Diverticulitis

When asked to confirm or exclude diverticulitis, abdominal ultrasound is a suitable initial test. Depending on location (colon/sigmoid) and the patient's build (slender vs obese), an infected diverticulum may or may not be visible

Trauma

Ultrasound examination may be used in the trauma room to exclude posttraumatic damage. This is also termed the FAST echo (FAST = Focused assessment with sonography for trauma).
The presence of intra-abdominal fluid can be assessed (fig. 51). The fluid (in this case blood) is often found around the spleen, surrounding the liver and in Morrison's pouch (= space between the liver and right kidney).