Written By: Pavitra Sampath | Updated : February 24, 2015 2:30 PM IST
These can reveal patterns of brain activity and impart information regarding the deposition of the amyloid or tau protein, thus differentiating in the type of dementia.
PET scan or positron emission tomography is a test that is commonly advised in cases where the doctor would like a better view of your internal organs while they are functioning. The advantage of this test is that it takes 3D images of organs while they are still working, therefore recording the exact changes that occur in a sequential manner, which is what makes it different from a CT scan or X-ray. A PET scan has proved to be a boon for diagnosing various conditions like heart disease, epilepsy, Alzheimer's and most importantly cancer. Want to know about a CT scan? Here are the answers to all your questions.
How does it work?
A PET scan works on the theory of grabbing emissions from a radioactive substance to form a 3D image. This radioactive substance is injected or administered to the patient before the test, making their organs emit different levels of radiation as they function.
The test is used to check for the presence of disease in the body and to identify exactly which part is affected. It is also known to be used in cases where a doctor would like to see how well a particular treatment is working.
Once an image is formed, it shows how the various parts of the particular organ that is being tested use the radioactive substance. This way a physician may be able to diagnose how an organ is functioning, why it is malfunctioning and how a certain disease is affecting it. An MRI is also another test that renders 3D images. Here is more about the test.
This is especially essential when it comes to testing the presence and reasons for certain conditions like:
A PET scan may also be used to check for defects in other parts of the body as well like the lungs, breasts etc.
How to prepare for the test and what it will feel like:
This test is not painful and usually requires little or no care after it has been performed. You will be asked to remove all or any jewelry you may be wearing before the test and be asked to change into a hospital gown as well. Therefore it is a good idea to wear loose and comfortable clothing that is easy to change out of.
Once you reach the hospital, the radiologist will either inject a radioactive material into your vein, ask you drink a solution containing the material or in some cases may ask you to inhale the substance. This is usually done one hour before the scan is actually taken as the radioactive substance will need that much time to circulate through your body. In some situations your doctor may also ask you to fast for eight hours before the procedure to allow for the proper imaging of the organs within your stomach.
You will then be given a hospital gown or dress and asked to enter the PET scan room and lie down on a bed attached to the machine. This bed will then be moved into a large doughnut shaped machine (this is the actual PET scan machine). While inside, you will be asked to stay still and breathe normally through the procedure. You will be closely monitored while inside the machine for any signs of panic or anxiety. You can even talk to the technician while inside through an inbuilt mike. The entire procedure usually takes about 30 to 60 minutes.
After the procedure you may return back to your daily routine, but will be advised to drink a lot of fluids to help your body flush out the radioactive material. Doctors suggest that the radioactive material be excreted from the body as quickly as possible.
What you should tell your doctor before the test:
Could this test lead to any complications?
While this is a fairly safe test there are a few things that might go wrong, for instance:
You may develop an allergy to the radioactive material. This is usually rare and the symptoms of the allergy will manifest during the first few minutes after its administration. This complication is usually resolved easily with drugs to flush out the material.
Anxiety or claustrophobia may make you panicky, dizzy and in some extreme cases even make you pass out. This is again manageable as the technicians will be at hand to help you feel more relaxed.
In some cases of serious illnesses like epilepsy you might suffer from an attack while in the PET scan machine. Although rare, your doctor and technicians will usually have first aid measures at hand to help you.
Have any more fears about undergoing a diagnostic test? Leave us a comment and we can help you with the answers.
You may also like to read:
For more articles, visit ourDiseases and Conditions Section. Health.India.com is now TheHealthSite.com. Follow the all-new site on Facebook and Twitter.
