Magnetic Resonance Imaging, originally known as Nuclear Magnetic Resonance Imaging, is a medical imaging technique that provides very detailed images of any part of the body. More sophisticated than the CT scan, the use of MRIs began in the mid 1970s and the scans are still an important diagnostic tool today, especially in the diagnosis of cancer.
By use of a powerful magnetic field, the MRI clearly shows the contrast of different soft tissues in the body. By changing exam parameters, the MRI can cause these tissues to take on different appearances. When this occurs, the radiologist who is observing the MRI can simply tell whether something inside the body is abnormal by the way it appears on the screen.
Unlike other diagnostic procedures, the MRI does not rely on radiation, making it an even safer procedure than most. Instead, when the body is inside the machine, radio waves redirect the axes of spinning protons, which are the nuclei of hydrogen atoms, in a strong magnetic field. This field is produced by allowing an electrical current to pass through wire coils inside the machine. Other coils that encircle the body send and receive radio waves, producing signals that are received by a computer. The signals generate images that each show a thin "slice" of the body. These images are then interpreted by a radiologist experienced in reading MRI results.
What to Expect ?
While the idea of having an MRI may make an individual nervous, mainly because they are frightened about what the doctor will find, there is nothing scary or painful about the MRI itself. This totally painless procedure is simple and is usually accomplished within just an hour or two at a hospital or some other sort of imaging center. Knowing what to expect helps the whole process go more smoothly and greatly reduces any fear.
Little needs to be done to prepare for an MRI. Some eating and drinking guidelines may apply before the test but, usually, patients may eat and drink as usual and may take their daily medications. In some cases, you may be asked to swallow a contrast dye, known as gandolinium. Fortunately, this dye does not contain iodine, which can cause an allergic reaction. Some health issues preclude the use of a contrast dye, so always be sure your doctor knows if you have kidney disease or other serious disorders.
When you arrive, you'll most likely need to fill out some paperwork and be asked to identify anything in your body that that may contain metal, like cochlear implants or screws or pins placed during surgery for broken limbs, etc. You'll be asked to remove jewelry and other metal items.
Once all paperwork is reviewed and appropriate items are removed, you'll be ready to begin. In the scanning room, patients are asked to lie on a large table. The technician will see that you're comfortable before the procedure begins. Once you are ready to begin, the technician will slide the table into the machine and leave the room.
At that point, the test starts. Usually, it is broken up into several different sequences, and the technician, who can still communicate with you, will tell you how long each will last - generally no longer than about 2 or 3 minutes. During that time, patients will hear banging noises, which is a normal part of the procedure and does not indicate any troubles. The entire test can range from 15 minutes to a few hours. When all is complete, the table will slide back out.
Some people get claustrophobic while undergoing an MRI, especially if it's a long procedure. This can be solved in a few different ways. First of all, your doctor can prescribe a mild sedative if you let him/her know in advance that you have an issue with claustrophobia. Secondly, some facilities offer open MRI machines that reduce that closed-in feeling. Some MRI machines have music piped in to help patients relax. Also, the technician may offer ear plugs to reduce noise.
Individuals undergoing an MRI should feel normal after the procedure though if contrast dye is used, it may cause temporary flushing or other minor reactions until it leaves the body.
Patients do not receive immediate results from an MRI. Technicians are not qualified or permitted to interpret images and cannot and should not offer any comments to the patient. The images will be viewed by a licensed radiologist and that individual will send results to the patient's doctor, who will then call to set up an appointment to review them.
If the MRI does show that mesothelioma is present, your doctor will refer you to an oncologist - a cancer doctor - who will instruct you on your options for treatment.
Do the Benefits Outweigh the Risks?
There are many benefits to undergoing MRI in the diagnosis of mesothelioma and other diseases. First of all, it does not expose patients to radiation as do other diagnostic procedures and the contrast dye used in MRIs is much safer than that used for CT scans. Furthermore, it is the most likely of all imaging tests to identify abnormalities and focal lesions on soft-tissue structures of the body, including the heart, liver, and other organs.