What is MRI?
MRI (magnetic resonance imaging) uses radio waves and a strong magnetic field to provide clear and detailed pictures of internal organs and tissues. This technique has proven to be very useful for the diagnosis of many types of conditions in all parts of the body, including cancer, coronary artery and vascular disease, stroke and joint and musculoskeletal disorders.
What are the benefits of MRI?
- Imaging of soft-tissues such as the heart, lungs, liver and other organs are clearer and more details than with other imaging techniques.
- MRI images can help your doctor evaluated function as well as the structure of many organs.
- MRI provides a fast, non-invasive alternative to X-Ray angiography for diagnosing problems of the heart and cardiovascular system.
- MRI can detect abnormal tissue that might be hidden by bone tissue when other imaging techniques are used.
- Exposure to radiation is avoided.
What are Risk of MRI?
- An undetected metal implant may be affected by the strong magnetic field.
- MRI is generally avoided during the first 12 weeks of pregnancy. Doctors usually choose other methods of imaging, such as ultrasound, unless there is a strong medical reason.
You should talk with your doctor to learn if there are any other benefits and risks specific to your procedure.
What will the exam be like?
You will lie comfortably on an MRI examination table. When you and the radiologist or technologist is ready for the examination, the table will be moved in to the MRI unit. The technologist or the radiologist will have you in full view at all time and be in constant communication with you via a two-way intercom.
You will be required tie lie still during the actual imaging process, but between images some movement is allowed. You will generally be required to lie still for only a few seconds to a few minutes at a time.
You will not feel any pain or discomfort during the imaging. You will hear the hum of the equipment as the images are being produced. Some patients find the loud tapping or knocking noises heard at a certain phases during the imaging the most bothersome.
Depending on the exam, you may be given an injection of contrast materials to make it easier to visualize certain tissues or blood vessels. The contrast material will usually be injected in an arm or head vein through a small needle connected to an IV (intravenous) line.
The contrast material will be naturally eliminated within a few hours to a day or two depending on the area examined and the type of contrast materials used.
What Does the equipment look like?
A conventional MRI unit is a closed cylindrical magnet in which you must lie still for several seconds at a time.
Open or “short-bore” MRI units are open on all sides or in some cases, are not fully enclosed. Like the conventional MRI, you will be asked to lie still for several seconds at a time.
How should I prepare for the exam?
- You will be asked to remove anything metallic including hairpins, jewelry, eye glasses, hearing aids and any removable dental work.
- The technologist or other staff will ask you if you have a prosthetic hip, heart pacemaker, implanted port, intrauterine device (IUD) or any metal plates, pins, screws, or surgical staples in your body, and whether head surgery has been done in the past.
- You will also be asked if you have worked with metal, or have had a bullet or shrapnel in your body. If there is any question of metal fragments, you may be asked to have an X-ray to detect any metal objects.
- Inform your technologist if you have tattoos or permanent eyeliner as this can sometimes create a problem.
- Tooth fillings are usually not affected by the magnetic field, but they may distort images of the facial area or brain, so the technologist or radiologist should be informed.
- Inform your technologist or radiologist of any drug allergies.
- Some patients who undergo MRI in an enclosed unit may feel confined or claustrophobic. If you experience undue anxiety, a sedative may be administrated. About 1 on 20 patients may require medication.
How will I learn the results?
A radiologist, who is a physician specializing in MRI and X- ray examinations, will analyze your images and report the results to your doctor.
The results of your MRI will be made available to you through your designated healthcare provider or doctor.
- Inform your radiologist or technologist if you have tattoos or permanent eyeliner, ever worked with metal, or have had a bullet or shrapnel in your body, if you have a prosthetic hip, heart pacemaker, implanted port, intrauterine device (IUD) or any metal plates, pins, screws, or surgical staples in your body as this can sometimes create a problem.
- Always inform your doctor and the technologists if you are pregnant of thin there is a possibility you may be pregnant.
- Advice your doctor or the radiologist of any allergies.
- Advice your doctor if you have any limitations or special needs that would affect you during the procedure.
- Inform the technologist if you are sensitive to latex or other substances.