La kidney scan is an exam that allows you to observe the how each kidney works, as well as their morphology.

Scintigraphy is a imaging technique which consists in administering to the patient a radioactive tracer, which spreads in the body or in the organs to be examined. Thus, it is the patient who “emits” the radiation that will be picked up by the device (unlike radiography, where the radiation is emitted by the device).

This exam is used for a variety of indications, including:

• measure the kidney function of each kidney (excretion), to assess the consequences of various kidney abnormalities and diseases, such as vesicourretal reflux.
• visualize the kidney morphology (malformations, presence of abnormalities or “scars”, abnormal location of a kidney, etc.)
• assess the sequelae ofkidney infection (pyelonephritis) or other diseases
• diagnose a problem with the blood circulation in a renal artery
• assess the impact of a narrowing or dilation of the urinary tract
• take stock in case of kidney tumor, kidney or bladder infection
• in case of abdominal and back pain or in case of blood in the urine, with no obvious cause identified.

Kidney scintigraphy does not require special preparation and is painless. However, it is essential to inform the doctor of any possibility of pregnancy.

Before the examination, the medical staff injects a slightly radioactive product into a vein in the patient’s arm. This will be filtered by the kidney and be evacuated in the urine, which allows to have an idea of ​​the quality of the renal function. Several products can be used depending on what you want to observe:

• technetium + DMSA to observe morphology, as it accumulates in kidney cells
• technetium + DTPA or MAG3 to observe kidney function, as these tracers are quickly excreted in the urine

Depending on the indication and the product used, the images should be taken immediately after the injection (30 to 40 minutes later for renal function) or a few hours after (4 to 6) to give the product time to get fixed in the kidneys.

To take the pictures, you will be asked to lie down on an examination table. A special camera (gamma camera or scintillation camera) will move quickly above you.

It is enough to remain motionless for fifteen minutes during the acquisition of the images.

After the examination, it is advisable to drink plenty of water to facilitate the elimination of the product.

Kidney scintigraphy can diagnose various malformations and diseases, follow up onknown kidney problems or a assessment in case of tumor or infection.

Depending on the results, the doctor will suggest appropriate treatment and follow-up. Other examinations may be necessary to make the diagnosis (ultrasound, CT scan, MRI, etc.).