CT KUB Scan: Overview, Purpose & Preparation

An Overview of CT Kub Scan

KUB is an abbreviation for kidneys, ureter, and bladder.
A computed tomography (CT) KUB scan is a non-invasive technique for diagnosing issues related to the urinary system.

A CT KUB may be recommended if a person is experiencing certain urinary tract symptoms, including pain or the presence of blood in their urine. In an emergency setting, CT KUB scanning is considered the first imaging option for suspected urolithiasis.
KUB scanning uses imaging and sometimes contrast material to diagnose issues like bladder and kidney stones, specific malignancies, and structural irregularities.
This article discusses why doctors may advise you a CT KUB scan, what to expect before, during, and after the scan, and some of the potential risks associated with the CT KUB scan.

What is a CT KUB scan?

Computed tomography (CT) of the KUB, also known as a CT KUB scan, is a medical imaging procedure that helps to obtain multiple pictures of the urinary system and adjacent structures from various angles using computer technology and X-rays. These pictures are then sent to a computer to generate cross-sectional or even three-dimensional images, which provide voluminous and useful information for detecting pathologies in the examined region.

CT KUB scan is the primary diagnostic study when investigating for:

• Haematuria (blood in the urine)
• Flank pain (pain on one side of the body, between the abdominal area and the back)
• Suspected urolithiasis

Sometimes an iodine dye or contrast material is administered through a vein during a CT KUB. This contrast medium flows into your kidneys, bladder, and ureter, thus highlighting the structures so that your doctor can visualise your urinary tract structures clearly and evaluate whether it is functioning correctly.

The contrast material is not always necessary for a CT KUB, and its use is usually case specific. Additionally, this material may not always suit every patient, especially those with pre-existing medical conditions.

Why is a CT KUB scan performed?

A CT KUB scan is done to examine the kidneys, bladder, and ureters. The scan helps the doctor to determine the size and shape of these organs, and detect any signs of disorder that could affect the urinary system.

A KUB CT may be recommended if you have symptoms that of a urinary tract disease, such as blood in the urine (haematuria) or flank pain.
A CT KUB may aid in the diagnosis of urinary system conditions, including:

• Bladder stones
• Kidney stones
• Cysts
• Tumours
• Complicated infections
• Structural issues
• Cancer

Non-contrast CT KUB scans are typically used to identify renal calculi (kidney stones), while contrast material may be administered to detect conditions such as necrosis or inflammation.

Preparing for a CT KUB scan

• No special preparation is needed for this scan. However, all metal objects, including jewellery must be removed because they can end up causing artefacts (abnormality in the image) and affect image quality.
• If you suspect you are pregnant, please notify a staff member well before the test. This examination might not be appropriate in such cases, or special precautions may be required. If you are unsure that are pregnant, a pregnancy test must be carried out prior to the examination.

◦ During a CT scan, no one permitted inside the examination room for safety reasons, and family and friends must wait outside. If the patient has any concerns, a staff member will communicate with them through a glass panel located nearby throughout the scan. Inform the staff if you have had any adverse reactions in the past to X-ray contrast dye or if you are taking any medications, including metformin, antibiotics, or non-steroidal anti-inflammatory drugs. Also, let them know if you have any medical conditions such as cardiovascular disorders, kidney problems, or asthma.

• Before a CT KUB scan, you may be instructed to drink water and hold your urine until the procedure is complete. This will cause your bladder to expand, which can help to produce clearer images. However, the instructions for what you should consume before the CT KUB scan may differ based on your specific condition.

What to expect prior to CT KUB scan?

Prior to your examination, a heath team member may:

• Inquire about your medical history.
• Check your pulse rate, blood pressure, and body temperature.
• Ask you to wear a hospital robe and remove any jewellery, metal objects, or eyeglasses, which may interfere with the X-ray.

What to expect in the scanning room?

A CT scanner typically has a large, doughnut-shaped structure. During the scan, you may receive a drug through a cannula, which can help generate more urine and aid in imaging your kidneys. Your radiographer will give you this drug just before injecting a contrast medium through the cannula.

Possible side effects of the contrast material include:

• Feeling flushed and hot for a few minutes,
• A metallic taste in your mouth,
• A sensation of passing urine without actually doing so.

Although a CT scan is open, some people may experience claustrophobia. If this is a concern for you, please inform the radiographer beforehand.

What to expect while getting a CT KUB scan?

• In all cases, you will be required to lie on your back on the machine table; however, there may be times when you must lie on your stomach.
• Your radiographer ensures that you are in the proper position. They sometimes do this with the help of cushions and foam shapes.
• They go out of the room and communicate with you over an intercom.
• The table slowly slides back and forth through the scanner hole. As you move through it, the machine takes pictures.
• The scan is not painful, but it may be uncomfortable as you must remain still. Notify your radiology technician if you feel stiff or need to move.

What to expect during the scan?

• The scanner will make a whirring noise, and that is normal.
• At times, your technician may ask you to hold your breath.
• They may also pause the scan and instruct you to take a walk around the room for a few minutes.
• They may also request that you use the restroom to empty your bladder. The scan is then completed.
• If your radiographer wishes for you to change positions, they will communicate with you over the intercom. Or they will return to the scanning room to assist you.
• When the scan is finished, your radiographer will return to the scanning room and lower the table so you can get up.

What to expect following your CT KUB scan?

After the contrast material injection, you will make asked wait in the radiology department for 15 to 30 minutes. This happens if you feel ill, which is uncommon.
Before you leave, your technician will remove the catheter from your arm.
You will be able to return home, to work post the scan. You will be able to consume food and drinks normally.

What are the potential risks associated with a CT KUB scan?

A CT or KUB scan is a safe exam for most people, but like all medical tests, it does have some risks.
Potential risks are:

Allergic reaction

Allergic reactions to contrast material is extremely rare. Symptoms typically include sweating, weakness, and difficulty in breathing, or hives. Before the contrast is administered, the radiology technician will ask you about any known allergies. If you are not sure about your allergy status and feel unwell after receiving the contrast, it is important to inform your technician immediately.

Swelling and bruising

It’s possible to experience a minor bruise around the area where the cannula needle was inserted. Additionally, there is a chance that the contrast dye may leak outside of the vein, which can cause discomfort and swelling at the site, though this is not very common.

Kidney issues

Your kidneys may be at risk of harm from the contrast material used in your scan, but the likelihood of this happening is low. To ensure that your kidneys are functioning properly and will not be adversely affected by the contrast material, your radiographer will examine your most recent blood test results before the scan.

Radiation

Radiation exposure during a CT scan could slightly raise the likelihood of getting cancer later in life. If this concerns you, consult your doctor.

Pregnancy

Pregnant women should undergo CT scans if necessary. If you happen to be pregnant or suspect you are pregnant, please inform the department as early as possible before the scan.

Takeaway

CT KUB scans are a valuable diagnostic tool for assessing the kidneys, ureters, and bladder. These non-invasive scans generate detailed pictures of the urinary system using X-rays and computer technology, aiding doctors in diagnosing and treating a variety of conditions.

While CT KUB scans are safe and well tolerated, there are some risks and potential complications, such as radiation exposure or allergic reactions to contrast dye. Patients who are scheduled for a CT KUB scan should discuss potential risks or concerns with their doctor, in addition to any medications or pre-existing illnesses that might impact the procedure.