Triple-Phase Abdominal CT- Procedure, Why it is done and How to prepare

Triple-Phase Abdominal CT, Triple-Phase CT, three phase CT scan, Computed Tomography

The triple-phase abdominal CT protocol is a useful examination in the assessment of abdominal structures inside the body.

Triple-Phase Abdominal CT- Procedure, Why it is done and How to prepare

Overview

The abdominal structures of our body include liver, kidneys, pancreas, spleen, GI tract, and the area around these organs.

Triple-Phase CT scan is an imaging method that uses X- rays to generate detailed pictures of the organs inside the abdomen. The patient is given contrast (dye) through oral consumption or intravenous injection.

It involves a dedicated late arterial phase, portal venous phase and delayed phase image acquisition.

Late arterial phase- The late arterial phase, also known as the corticomedullary phase or early venous portal phase, is a contrast-enhanced CT or MRI series, in which there is an optimal enhancement of structures that get their blood supply directly from the arterial system.
Portal venous phase- The portal venous phase, also known as the late portal phase or hepatic phase, is a contrast-enhanced CT or MRI series which is characterised by-
- Portal veins are fully enhanced.
- Hepatic veins are enhanced.
- Liver parenchyma is at peak enhancement.
Delayed phase acquisition- Comes after the portal venous phase(PVP) and with the following characteristics:
- Portal and hepatic veins are enhanced but less than in PVP.
- Liver parenchyma is enhanced but usually less than in PVP.

Typically acquired 2 to 5 minutes after injection.

Compared to traditional CT scans, triple-phase CT scan is more sensitive and gives clearer images.

This type of CT scan is used to diagnose certain types of cancer such as-

Renal pelvis- Renal pelvis is the area at the centre of the kidney where urine is collected and is funnelled into the ureter
Hepatocellular- Hepatocellular carcinoma is the most common type of primary liver cancer and occurs most often in people with chronic liver diseases, such as cirrhosis caused by hepatitis B or hepatitis C infection.
Lymphoma- Lymphoma is a cancer of the lymphatic system, which is part of the body's germ-fighting network. The lymphatic system includes the lymph nodes (lymph glands), spleen, thymus gland and bone marrow. Lymphoma can affect all those areas as well as other organs throughout the body.
Melanoma- Melanoma, the most serious type of skin cancer, develops in the cells (melanocytes) that produce melanin — the pigment that gives your skin its colour. Melanoma can also form in your eyes and, rarely, inside your body, such as in your nose or throat.
Ovarian- Ovarian cancer is a growth of cells that forms in the ovaries. The cells multiply quickly and can invade and destroy healthy body tissue.
Pancreatic- Cancer that begins in the organ lying behind the lower part of the stomach (pancreas).
Pheochromocytoma- Pheochromocytoma is a type of neuroendocrine tumor that grows from cells called chromaffin cells. These cells produce hormones needed for the body and are found in the adrenal glands. The adrenal glands are small organs located in the upper region of the abdomen on top of the kidneys.

When is Triple-Phase Abdominal CT done?

You may need this test if you have symptoms such as-

Blood in urine
Abdominal pain
Swelling
Hernia
Kidney stones

How to prepare for the test

Pregnant women should inform their doctor (and x-ray technician) as the radiation may affect the fetus. If needed, precautions can be taken to lower the radiation exposure to the fetus.
You may have to remove your jewellery and any metal objects which might interfere with the image.
If you are diabetic or under any other medication/ treatment, you must let your treating physician know.
You will receive instructions regarding fasting from your physician prior to your appointment.