|
SCINTIGRAPHY
Nuclear medicine is a medical imaging technique that allows the production of images of the human body with the help of radioactive products. This technique is safe and painless.
While diagnostic radiology mainly assesses organ and tissue anatomy, nuclear medicine allows the evaluation of the functioning of the studied structure.
During nuclear medicine examinations, a radiopharmaceutical product (radioactive isotope) emitting gamma rays is injected through intravenous route or administered orally. It will bind to the targeted organ.
Then, after a certain time, the imaging is done using a gamma camera. This camera will detect each gamma ray emitted and generate an image called scintigraphy.
Nuclear medicine imaging techniques are part of the diagnostic tools that allow very early detection of abnormalities that might not be seen through other imaging techniques.
 Bone scintigraphy (bone scan)
Bone scintigraphy is a very effective examination to monitor the evolution of bone metastases secondary to a cancer, or to assess the severity of a bone and articular disease such as osteoarthritis or arthritis.
Bone scintigraphy also allows the localization of a lesion and the determination of its etiology when the patient feels pain but the radiography shows no abnormality. Very small lesions can be detected, such as stress fractures.
Preparation: None
Approximate duration: 3 to 4 hours
(but you can leave the clinic between the time of the injection and that of the scan)
 top of page
Myocardial perfusion scintigraphy
 The myocardial perfusion study is an examination which aims to determine if your cardiac muscle receives the blood supply needed. The coronary arteries bring to the cardiac muscle the amount of blood necessary to ensure its proper functioning. If those arteries become partially obstructed by fat deposits or calcium deposits (atheromatous plaque), it becomes important to receive the appropriate treatment.
This diagnostic tool is therefore appropriate to indentify patients who require more invasive procedures such as coronary angiography. The myocardial perfusion examination is also used to evaluate the effectiveness of treatment involving anti-angina medication, and to assess the damage caused by a myocardial infarction. In addition, it allows the assessment of the risk of cardiac failure in patients showing the following risk factors:
- high blood pressure;
- excess weight;
- sedentariness;
- diabetes;
- hypercholesterolemia;
- tobacco consumption;
- unhealthy eating habits and excessive alcohol consumption;
- unfavourable family history.
Myocardial scintigraphy is performed in two steps:
- step 1 – at rest;
- step 2 – during treadmill testing or under
pharmacological stimulation with Persantine®.
During both steps, a radioactive product is injected into the patient. This product will bind to the heart depending on the blood flow through the coronary arteries.
The nuclear medicine specialist will make a diagnosis by comparing the images obtained during both steps.
Preparation:
- You must be in a fasting state since midnight the night before the examination (patients with diabetes may eat a light breakfast and take their insulin).
- Avoid tea, coffee, sodas, smart drinks and chocolate for 24 hours before the examination (no caffeine).
- Bring a list of your medication.
- Unless otherwise advised by your physician, take your medication with a little water.
Approximate duration: 3 to 4 hours
top of page
Nuclear ventriculography (MUGA)
This examination allows the evaluation of the contractile force of the left ventricle, the part of the heart that pumps the blood into the whole body. Some medications (e.g. used in chemotherapy treatment) and cardiac conditions (e.g. post infarction aneurism, dysfunction of cardiac valves) can affect the force of this ventricle. It is therefore important to evaluate the ejection fraction to avoid medical complications (e.g. pulmonary edema, shortness of breath).
Preparation: None
Approximate duration: One hour
top of page
Renal Scintigraphy
The study of kidneys in nuclear medicine allows the evaluation of several renal function abnormalities. The examination can be performed with or without medication:
With Captopril: For the diagnosis of the origin of renovascular hypertension.
With Lasix®: To show obstruction of the urinary tract.
Renal morphology is another aspect that can be studied by nuclear medicine. This technique is used to evaluate the condition of the renal cortex in cases of pyelonephritis or cyst.
Preparation: Information will be provided when appointment is made by telephone.
Approximate duration: 2 to 3 hours
top of page
Thyroid Scintigraphy
With the images obtained through thyroid scintigraphy, it is possible to determine the size of the gland and its location in the neck, and to localize areas of abnormality. This examination is useful to characterize the function of a node discovered by your physician or visualized through ultrasonography.
If a malfunction of the metabolism of the thyroid gland occurs, it will affect the level of thyroid hormones in the blood, thus causing hyper or hypothyroidism. In such cases, we can evaluate the rate of iodine uptake by the thyroid gland with a simple procedure: the patient must drink a small quantity of slightly radioactive iodine (iodine-123) and, a few hours later, scintiphotos will be produced, therefore allowing for the completion of the examination in one day.
Preparation: Information will be provided when appointment is made by telephone.
Approximate duration: One Hour
Five hours if the examination is performed with iodine-123 (but you can leave the clinic between the administration of iodine and the moment when the photos are produced).
top of page
Parathyroid Scintigraphy
This examination is used to determine the location of one or several parathyroid adenomas which can cause hyperparathyroidism.
Preparation: None
Approximate Duration: 4 hours
top of page
Hepatic System Scintigraphies
In nuclear medicine, there are several types of examinations for the evaluation of the hepatic system. Liver-spleen scintigraphy allows the evaluation of the condition of hepatic and spleen cells. Through this examination, focal lesions (cyst, abscess) or diffuse dysfunctions (steatosis, cirrhosis) can be detected.
Also, red blood cells scintigraphy is very efficient to confirm the presence of a liver hemangioma when other types of imaging technology provide inconclusive results.
Finally, it is possible to evaluate the condition of the bile duct by visualizing bile formation and elimination. This examination is particularly useful to diagnose cholecystitis, which is an obstruction of the bile duct caused by a mass or a stone.
Preparation: Information will be provided when appointment is made by telephone.
Approximate duration: 3 to 4 hours
top of page
Scintimammography
Scintimammography is often performed to complement a mammography examination. It facilitates diagnosis in patients where breast evaluation through conventional examinations is difficult (dense or voluminous breast, presence of prothesis). It is interesting to note that, as opposed to mammography, the images are obtained without compression of the breast.
Preparation: None
Approximate duration: One hour
top of page
White Blood Cells Scintigraphy
This imaging technique allows the localization of certain areas of inflammation and infection:
- osteomyelitis and septic arthritis;
- fever of unknown origin;
- chronic inflammatory bowel disease;
- loosening of hip or knee prosthesis.
The examination is performed as follows: a blood sample is taken in order to extract a sufficient amount of white blood cells. Then, a slightly radioactive isotope is mixed with the patient’s white blood cells and re-injected intravenously. A few hours later, scintiphotos are produced. They are used to determine if there is an excessive concentration of white blood cells in the evaluated area, which indicates the presence of infection or inflammation.
Preparation: None
Approximate duration: 6 to 8 hours
(but you can leave the clinic between the first and the second part of the examination).
top of page
|
