Renal Ultrasound is also known as a kidney ultrasound. It is a diagnostic exam that produces real-time images of the size, shape, and location of the kidney as well as the ureters (thin tubes that carry urine from the kidney to the bladder) and bladder.

The kidneys are located just above the waist towards the back of the abdominal cavity and its function is to produce urine from liquid waste products it removes from the blood, regulate blood pressure and maintain a stable balance of salts in the blood.

A kidney ultrasound exam usually includes the ureters and bladder because the waste products which the kidney removes from the blood (urine) is carried by the ureters and stored in the bladder. You will be asked to keep a full bladder by drinking plenty of water.

Reasons for Performing a Renal Ultrasound

A kidney ultrasound may be recommended by a doctor they suspect a kidney or bladder malfunction. Since ultrasound scan are used to produce real-time images of the internal organs/structure, renal ultrasound can be used to assess and diagnose a variety of condition such as;

  1. Kidney stone or blockage: Hardened crystalline deposits made of certain minerals that are formed in the kidney.
  2. Tumor: An abnormal growth of tissues or cells that may cause abdominal swelling, bloating, and pain.
  3. Abscesses: A collection of pus that has buildup within the body’s tissue.
  4. Cysts: Accumulation of fluid or lump of fluid.
  5. Buildup or obstructions: Swelling of the kidney due to urine buildup.
  6. Urinary tract infection
  7. Collection of fluid from a cyst or kidney abscess.
  8. To assist the doctor in the placement of a drainage tube into the kidney.
  9. To guide the doctor during a tissue biopsy of the kidney.

Who Performs the Renal Ultrasound

Renal ultrasound is performed by an ultrasound technologist or technician. A diagnostic radiologist or sonographer is a medical professional who is trained to carry out ultrasound scans and interpret ultrasound images.

They specialize in interpreting medical imaging tests including MRI scans, ultrasound, and CT scans.

Preparation for a Renal Ultrasound

An ultrasound scan does not require special preparation but for a renal ultrasound, you will be asked not to eat or drink anything except water for about eight hours before the scan. In order to keep a full bladder, you may have to drink plenty of water an hour before the scan.

Procedures of Renal Ultrasound

Renal ultrasound is performed in an ultrasound room in a hospital. The procedure of the renal ultrasound takes less than thirty minutes generally. Steps include;

  1. Lying down face up on a table in the ultrasound room which usually has dark or dimly light, to enable easy reading of the ultrasound images on the ultrasound screen.
  2. A clear water-based gel or conductive gel will be applied to your skin on the area under examination to reduce friction and help the transducer slide across your skin. It is the transducer that sends and receives sound waves to produce the image on the ultrasound screen.
  3. The technologist will move the transducer back and forth on the area under examination and occasionally press the transducer down while looking at the screen to enable him to capture the desired image that will help diagnose your condition.
  4. The water-based gel is then wiped off from your skin.
  5. You may be asked to wait for some time while the diagnostic radiologist checks if the imaging was complete.
  6. After an imaging test, the patient is usually asked to go home.

What you may experience during and after a Renal ultrasound

During a renal ultrasound, you may experience minimal discomfort which is usually temporary as the transducer presses against your skin.

After the renal ultrasound, you will be asked to dress and sit for a while as the result is being reviewed. You may be given the results or asked to return to the hospital in a few days and should be able to resume normal activities after an ultrasound scan.

Although you may be asked to do further tests if the test results appear to be abnormal.

Benefits of Renal Ultrasound

Some known benefits of Renal ultrasound are listed below:

  1. It is painless although it may be uncomfortable temporarily.
  2. It is noninvasive which means that there are no injections or needles.
  3. It is used as a tool for guiding minimally invasive procedures such as needle biopsy.
  4. It is less expensive and easy to use compared to other imaging methods.
  5. It is widely available compared to other imaging methods and provides great internal details when accessing soft tissue structures.
  6. It is completely safe and it uses sound waves, not radiation.
  7. It provides a more clear picture of soft tissues that did not show up clearly on the x-ray.

Risks/complications of Renal Ultrasound

Although standard ultrasound diagnostics do have a known harmful effect on the human body, but an interpretation of the ultrasound may lead to other procedures such as biopsy and followups.

Limitation of Renal Ultrasound

Though ultrasound scan is painless and has no known harmful effect on the human body, Renal ultrasound limited by some factors such as intestinal gas and obesity.


Renal ultrasound has to do with scanning the kidney, ureters, and bladder for abnormalities because they are connected. Ultrasound is painless so you do not have to panic although you may be asked to carry out other medical tests depending on the outcome of the ultrasound.

Always feel free to ask your doctor questions about scan results especially if you do not understand.