Ultrasound Bladder

Bladder Ultrasound 

The bladder must be filled for adequate evaluation.  A filled bladder has thin walls with hypoechogenic content (fig. 13). A filled bladder creates a perfect acoustic window for evaluation of the distal ureteral orifices in the bladder posterior wall.

Spleen

A healthy spleen has a homogeneous reflection pattern, smooth contours and a craniocaudal length of about 12 cm at adult age (fig. 14). The echo reflection pattern is similar to that of the liver in most patients. The spleen may also act as an acoustic window for evaluation of the pancreatic tail.

Pancreas

The pancreas cannot be imaged effectively when there is significant air content in the stomach/duodenum or transversal colon.
The lienal vein may help localize the pancreas as the pancreas is draped, as it were, over the lienal vein (fig. 15). It may also help to ask the patient to make a round tummy (Valsalva), which will move the pancreas towards the abdominal wall and increase visibility. The spleen may act as an acoustic window for evaluation of the pancreatic tail. The pancreatic duct has a diameter of 2-3 mm in most cases.

Because of its position, the pancreas is not always fully visible in any plane (fig. 16); angulating the echotransducer and/or moving it in the craniocaudal direction will allow for evaluation of as much of the pancreatic parenchyma as possible. 
Note: air content in the stomach/duodenum or transversal colon may reduce visibility of the pancreas (the tail in particular!).

The echo reflection pattern of the pancreas may differ between patient/age categories.  The echo reflection pattern will become more echogenic with age.

Aorta

The abdominal aorta is located centrally in the abdomen (fig. 17). It can be difficult to image it effectively, particularly with significant obesity and extensive intestinal gas. Adequate compression is necessary.Abdominal aorta dimensions (fig. 18):  

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