What Is a DMSA Scan?
A DMSA scan is an imaging test that uses radioactive material to create special images of the kidneys. These images help the doctor assess and diagnose kidney-related abnormalities. The images obtained from the DMSA scan also help to detect scarring and infection of the kidneys. This test mainly uses a radioactive compound that is injected into the veins and allows the doctor to obtain images of the kidneys and the surrounding structures. The radioactive material used in the DMSA scan emits gamma rays, allowing the doctor to obtain the images through a gamma camera.
What Are Kidneys?
The kidneys are one of the most crucial organs of the urogenital tract. A pair of bean-shaped kidneys are present below the rib cage, but both the kidneys are present at a slightly different level. The right kidney is lower than the left because the liver occupies the space above the kidneys. The kidneys consist of the renal cortex, renal medulla, and renal pelvis. The main functions of the kidneys are listed below:
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Filters the blood and removes the toxins and waste products from the urine.
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Synthesize the hormone renin to maintain the body’s blood pressure
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Regulate the pH (potential of hydrogen) of the blood.
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Regulate the RBC (red blood cell) levels.
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Regulate the mineral and electrolyte levels of the body.
What Are the Uses of a DMSA Scan?
DMSA scan is used to check the structure and size, and shape of the kidneys. It is commonly done in children who have been diagnosed with urinary tract infections. It specifically shows the areas of the kidneys that are working well and the ones that are scarred. The other conditions for which a DMSA scan is used are listed below:
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Pyelonephritis -The inflammation of the kidneys that occurs due to bacterial infection is known as pyelonephritis. It is commonly seen in women and can cause permanent damage to the kidneys if not treated at the right time.
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Renal Ectopia - It is a condition in which the kidneys are not located at their normal position. They are situated at some abnormal position in the body.
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Infarction - It occurs when the blood supply of the kidneys becomes interrupted due to several reasons.
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Hypertension - Renal hypertension is a condition that develops due to the narrowing of the arteries that supply blood to the kidneys.
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Horseshoe Kidney - Horseshoe kidney is also known as renal fusion and is a rare congenital condition. The baby is born with fused kidneys, and this fusion occurs even before birth. The fused kidneys resemble the shape of a horseshoe, hence the name.
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Acute Renal Failure - Acute kidney failure usually occurs when the kidneys lose their ability to filter blood and eliminate waste products from the body. As a result, the toxic substances accumulate in the blood resulting in a life-threatening condition known as blood poisoning (septicemia).
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Multicystic Dysplastic Kidney - When the kidneys fail to develop normally by birth and show multiple cysts, the condition is known as multicystic dysplastic kidney.
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Trauma - The kidneys might get injured due to trauma or accidents. A DMSA scan helps identify the cause of the injury.
How Should the Patient Prepare for the DMSA Scan Procedure?
No special preparations are required for this procedure. However, the patient must keep in mind the following things before the procedure:
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The doctor explains the procedure, the benefits, and the side effects associated with it. If the patient is willing to undergo the same, the patient needs to sign a consent form. The form states that the patient is ready for the procedure and is not under any pressure.
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The patient should also inform the doctor about the medications or any allergies or disorders that the patient is suffering from. For example, the doctor might ask to stop taking drugs like Aspirin and Ibuprofen before the surgery, as they can cause excessive bleeding.
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The patient needs to inform the doctor if the patient is allergic to the contrast medium or the dye so that the procedure can be carried out by taking the required precautions.
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The patient should not eat anything the night before the procedure and only take the prescribed medication in the morning before coming for the procedure.
What Happens During the DMSA Scan?
DMSA scan is a non-invasive procedure, so the patient must not be worried about it. The steps of the procedure are listed below:
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First, the doctor attaches an intravenous line to the patient’s arm.
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A local anesthetic will be injected to numb the area. If the procedure is to be carried out on a child, a topical anesthetic will be applied to anesthetize the area.
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The doctor might order a urine test before the procedure to make sure the patient does not have urinary tract infections. This is because infections can alter the scan results.
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After the radioactive material is injected into the body, the doctor will wait for an hour to allow it to travel around the body and accumulate in the kidneys.
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After the time is over, the doctor uses a gamma camera to take pictures of the kidneys as the substance travels through the body.
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It takes around 30 minutes for the doctor to take the pictures, but the patient must remain still throughout the procedure.
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Finally, the patient will be asked to urinate after the procedure to eliminate the radioactive substance from the body.
What Happens After the DMSA Scan?
The patient must drink plenty of water after the scan and frequently urinate so that no amount of radioactive material remains in the body. The patient must not worry because the scan will not affect the urine color. However, as the substance contains a radioactive tracer, the patient must wash the hands properly after going to the toilet. If a child or a toddler has undergone this procedure, the parents must make sure to wipe from front to back to avoid any complications. In addition, the patient must avoid coming in contact with a pregnant female or a breastfeeding mother for some time.
Conclusion
DMSA scan is a safe, convenient, and non-invasive procedure to detect kidney and urinary tract abnormalities. The biggest advantage of the procedure is that it has hardly any complications. Sometimes the patient might develop an allergy to the substance used in the scan, but that rarely happens. So, the patient need not do any special preparations before the procedure and consult a doctor to learn more about the procedure.
