The Differences of a CT scan, an MRI and PET scan medical imaging machine
CT Scan uses and Expectation on your scan
Another frequently used medical imaging machine is ct scan the abbreviation “CT” stands for computed tomography a medical imaging equipment which takes many xray at different angles and uses a computer to create a 3 dimensional picture of the inside of the body. The CT scanner consist of a moving couch not particularly narrow, that slowly move a person to that through a hoop that has a shape of a very large donut. The vast majority of any people will not experience of claustrophobia.
You will be held on the scanner couch by the radiographer, these days most people going to scanner feet first. Before the scan starts a small needle will usually inserted to your arm for the injection of the contrast medium. This is a liquid that enhances the definition of the scan. You go through the scanner twice, the first time is to get a general picture of the whole body which known as the localizer. The the second is to obtained the detailed scan. The actual scanning will only last on about 20 seconds. During which time depending on procedure you’ll be ask to hold your breath.
What is an MRI and what will you expect from it?
MRI scan is a more recent innovation of a medical imaging machine. A MRI scan uses magnetism to build up a 3 dimensional image on the inside of the body. Like the CT scanner the MRI scanner also consist of moving couch this slowly move a person into a cylinder and can be quite narrow and some people find that this gives a feeling of claustrophobia.
There are few open MRI scanner available for patient who suffer a claustrophobia which reduce this tunnel effect. You will usually go into the tunnel feet first, the radiographer will give you an emergency buzzer so if you have any concern you can immediately alert the staff. You can also talk to the nurses or radiographer while you are in the scanner. As the scan uses magnetism you need to make sure that you have already been removed all metallic objects. You also need to tell the radiologist if you have any internal metal object such as pacemaker or if you have any surgical clips. Before the scan starts a small needle is inserted into your arm for the injection of the contrast medium. While the scanner is taking place it can be noisy, as the scanners produces a repeated knocking sound, you’ll be offered a head through which music will be played on its ok you can choice the music you prefer to help reduced the noise and help relax you. The scan last for 30 minutes to an hour.
PET Scanning and Purpose of this machine
The latest development in medical imaging is the pet scan. PET stands for Positon Emission Tomography. In this scan you will be given an injection of a rapidly acting radioactive substance which disappear from the body in a few hours. The common radioactive substance use is a radioactive form of glucose.
The PET scan is not as good as CT or MRI scanning giving a good 3 dimensional picture of the body and its therefor usually used together with a low dose CT scan to help produce a better picture. Sometimes a PET scan maybe combine with a full CT scan. The advantage of the PET scan is that the radioactivity helps to tell what is inside on a shadow shown in a CT scan images, in particular whether it is a cancerous or not. For example a cancer may have enlarge lymph glands may to it, and it maybe uncertain as to whether they are enlarge because of cancer or for another reasons.
The PET will help often sort out this delema. PET scan can also be helpful after treatment for a cancer to sort out whether the remaining lump is active cancer or its dead or scar tissue the PET scan are also consist of a moving couch that slowing moves the patient into a small tunnel. This is a little bit narrow rather than the CT scan but much wider than the MRI scan and most people don’t find that it’s causes it in claustrophobia.
About an hour before the scan starts, a small needle is inserted into your arm for the injection of the radioactive substance. The time is necessary for the radioactive substance to be taken off by the tissue. Unlike the CT and MRI scan you usually going to the scanner head first your going to the scanner twice, the first time you get the CT scan and secont time you’ll get the PET scan. The CT scan just take a few seconds but the PET scan take around an hour.
In diagnosing the cancer ultrasound scan, CT scan, PET Scan and MRI scan are often complimentary and may give different information. For example for some cancers CT scan will give more accurate information whilst for other MRI scan are better for others a PET CT scan may gives the best information. So the choice of which the sort of scan are use depends on which type of cancer is suspected will being investigated. Often a combination of some or occasionally all of this scans maybe use in an individual.
