Ultrasounds are a noninvasive, sound wave technology for producing images of bodily organs and structures. Kidney ultrasounds, also called renal ultrasounds, specifically target the kidneys and bladder. A device known as a transponder is placed on the patient’s skin. It emits sound waves, which penetrate the body, bouncing off organs and generating data that a computer transforms into on-screen images. Physicians use ultrasounds to diagnose medical symptoms and determine appropriate courses of treatment. Ultrasounds have a critical safety advantage over X-rays of not relying on radiation to produce images.

Chronic kidney disease and other related conditions are an underreported health threat to many Americans. If you are concerned about your renal health, see the specialists in urology and nephrology at Baptist Health.

Why Do I Need a Kidney Ultrasound? What Does It Show or Detect?

An ultrasound offers a detailed picture of the kidneys’ size, shape, and disposition within the body. Your physician might order a kidney ultrasound if he or she thinks you’re suffering from:

• Nephrolithiasis (kidney stones)
• An infection
• Blockage
• Cysts
• A tumor
• An abscess
• Fluid collection.

Kidney ultrasounds are also used to assist in draining fluids and collecting tissues samples (biopsies). When used with a contrast dye, ultrasounds can also document blood flow within the kidneys.

How Do I Prepare for a Kidney Ultrasound?

There is little in the way of preparation for a kidney ultrasound. The primary requirement is to drink at least 24 ounces of a clear liquid an hour or more before the procedure. This is because a kidney ultrasound is also a bladder ultrasound and your physician will want images of your bladder both before and after you empty it.

There is no fasting requirement for a renal ultrasound.

What Should I Expect During a Kidney Ultrasound Procedure?

Kidney ultrasounds are performed in both inpatient and outpatient settings. The following steps apply:

• You’ll prepare for the procedure by removing your street clothes and any jewelry that you’re wearing. A hospital gown will be provided for you to change into.
• You will be positioned on your stomach in the examination area.
• A gel will be applied on the skin where the transducer goes. This substance serves to heighten contact between the transducer and your skin, improving sound wave transmission into the body.  
• The transducer emits sound waves into the body. These waves will reflect off the kidney and other internal structures and, on being captured by a computer, will provide the data it needs to create an image of your organs.
• The images created by the ultrasound will go into digital storage, for future reference.
• Multiple images of your bladder, both before and after urination, will be taken. This will assist your physician in interpreting the ultrasound data, because of the close working relationship between the kidneys and bladder.

What Are the Risks of a Kidney Ultrasound?

Kidney ultrasounds are essentially risk free. Because they utilize sound waves rather than radiation to produce images, ultrasounds are considered safer to patients and healthcare workers than X-rays. Certain conditions, such as obesity and abdominal gas, may limit the effectiveness of kidney ultrasounds.

What Happens After I Get a Kidney Ultrasound?

There are no limitations regarding diet or activity following a kidney ultrasound. You’ll want to meet with your physician, to hear his or her analysis of your exam, and to discuss next steps in your care.