Nuclear medicine is a safe and painless medical imaging procedure that allows radiologists to obtain specific images of the human body with the help of radioactive products.
This practice is part of the diagnostic tools that allow very early detection of abnormalities that might not be seen through other imaging techniques. Contrasting from diagnostic radiology that mainly assesses organ and tissue anatomy, nuclear medicine allows the evaluation of the inner functioning of the studied structure.
This technique necessitates the use of a radiopharmaceutical product (radioactive isotope) emitting gamma rays that is injected through intravenous route or administered orally to subsequently bind to the targeted organ.
Afterward, the imaging is obtained using a gamma camera that detects each gamma ray emitted and generate an image called scintigraphy. The amount of radiation emitted during a nuclear medicine procedure is comparable to that received during an X-rays exam, regardless of how many images are taken.
Today, nuclear medicine offers nearly one a dozen type of examinations that may be useful to a wide variety of medical specialties such as pediatric, oncology or cardiology.
Bone Scintigraphy (Bone Scan)
A bone scintigraphy scan provides a significant amount of information on the skeletal system. Hence, it allows the assessment of all of the body bones, without even increasing the radiation dose received by the patient. For instance, this exam could be used to observe 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.In addition, since the bone scan is an extremely sensitive, it allows the localization of a lesion and the determination of its etiology when the patient feels pain with a general radiography that shows no abnormality. For instance, bone scintigraphy can locate and determine the etiology of a lesion when the patient feels pain, but the radiograph is normal. Very small lesions could then be detected, such as stress fractures.
This exam requires no preparation and has an approximate duration of 3 to 4 hours. Note however that you do not have to stay at the clinic between the time of the injection and the moment when the photos are produced.
Myocardial Perfusion Scintigraphy
The myocardial perfusion study aims at determining if your cardiac muscle receives the blood supply desirable. If your coronary arteries become somewhat obstructed by fat deposits or calcium deposits (atheromatous plaque), it becomes preferable to receive the appropriate treatment. With the myocardial perfusion technique, the risk that an event occurs in a patient who gets a normal result are only less than 1% in the year following the test
In addition, the myocardial perfusion examination can also be helpful to evaluate the success of treatment involving anti-angina medication, and to assess the damage caused by a myocardial infarction.
The myocardial perfusion scintigraphy is especially useful for practical patients showing the following risk factors:
- tobacco consumption;
- high blood pressure;
- excess weight;
The myocardial scintigraphy exam is performed in two stages: a study of your body at rest and during treadmill testing or under pharmacological stimulation with Persantine. During both steps, a slightly radioactive product (Tc99m-sestamibi) is injected into the patient, a substance that will blind to the heart to generate a set of two images (one at rest and one other during exercise). The nuclear medicine specialist will then make a diagnosis by comparing the images obtained during both part.
Myocardial Perfusion Scintigraphy
We recommend that you bring a list of your current medication, come with comfortable shoes and unless otherwise directed by your doctor, take your medications with a little water. Avoid caffeine (tea, coffee, sodas, smart drinks and chocolate) in the 24 hours before your examination. In addition, you must be in a fasting state since midnight the night before the examination. Patients with diabetes may however eat a light breakfast and take their insulin.
This exam has an approximate duration of 3 to 4 hours.