Preparation:

-1-4 years old: Nothing to eat or drink for four hours prior to the exam.

-Over 5 years old: Nothing to eat or drink for six hours prior to the exam (the last meal should be a low-fat meal).

-Adults: Don’t eat or drink anything 8 hours before the test (overnight fast). If you are diabetic or need some medication according to your Doctor’s prescription, take your pills if necessary, with small sips of water. No carbonated, sweetened, or caffeinated beverages, could possibly interfere with test results. 

The study should be performed early in the day to minimize bowel gas interference. The patient should not chew gum or smoke the morning of the exam, this may increase the swallowing of air. 

The indications for an ultrasound examination of the renal arteries and veins are: 

-Workup of hypertension (atherosclerotic stenosis, fibromuscular dysplasia).

-Differentiation of <50% stenosis, higher-grade stenosis, and occlusion.

-Follow-up after repair (operation, PTA with/without stenting).

-Suspected renal infarction.

-Aortic aneurysm (spatial relationship to renal artery origins).

-Aortic dissection (possible involvement of renal arteries).

-Transplant kidney (anastomotic stenosis, rejection). 

Contraindications and limitations may include the following: 

-Open abdominal wounds, sutures, or staples.

-Drains and/or peritoneal dialysis catheters.

-Emphysematous breathing patterns, inability to hold breath.

-Overlying bowel gas.

-Obesity.

-Large firm/tense abdomen.

-Limitations in ability to change positioning.

-Patient cooperation.