Drawbacks of MRI scans include their much higher cost, and patient discomfort with the procedure. The MRI scanner subjects the patient to such powerful electromagnets that the scan room must be shielded.
MRI is also contraindicated in the presence of internal metallic objects such as bullets or shrapnel, as well as surgical clips, pins, plates, screws, metal sutures, or wire mesh. If you are pregnant or suspect that you may be pregnant, you should notify your physician.
An MRI machine uses powerful magnets that can attract any metal in your body. If this happens, you could get hurt. It can also damage equipment that's implanted in your body -- a pacemaker or cochlear implant, for instance.
The exact time required depends on whether you need a contrast dye for the procedure, but MRIs always require more time for the scan. A typical CT scan lasts 10 minutes whereas MRIs can take up to an hour or longer.
MRI is thought to have no long-term side effects, conversely to ionizing radiation-based imaging techniques (x-ray angiography, coronary computed tomographic angiography, and nuclear imaging), which can induce cell death or persistent DNA damage, resulting in mutagenesis, carcinogenesis, and genomic instability.
If the thought sends shivers down your spine, there's some good news: MRIs often aren't as scary as they seem. In case you're not familiar with the test, an MRI uses a magnetic field and radio waves to make detailed pictures of your insides.
In conclusion, although MRI is a highly sensitive diagnostic tool, it is also highly unspecific and its results are often poorly correlated with a patient's symptoms. MRI's can also make pain worse by instilling fear and anxiety in patients who conclude that the cause of their pain is what is seen in their scan.
MRIs are not known to cause side effects in most people and can be powerful tools to provide an accurate diagnosis. The images generated by an MRI can help diagnose complex and rare conditions, allowing them to be treated quickly and efficiently.
Magnetic Resonance Imaging (MRI): Brain
An MRI (magnetic resonance imaging) is a safe and painless test that uses magnets and radio waves to make detailed pictures of the body's organs, muscles, soft tissues, and structures. Unlike a CAT scan, an MRI doesn't use radiation.
False-negative diffusion-weighted imaging is especially prevalent in patients with posterior circulation and lacunar strokes [4-7]. One study in patients presenting with acute vestibular symptoms describes false-negative MRI scans in up to 53% of small strokes (< 10 mm) and 7.8% of large strokes (> 10 mm) [8].
In general, a CT scan has the advantage of short study time (15 to 20 minutes) with high quality images. However, disadvantages include the need for ra- diation exposure and the use of a contrast material (dye) in most cases, which may make it inappropriate for patients with significant kidney problems.
Generally, an MRI can help your doctor identify what is causing your health issue so that he or she can diagnose you accurately and prescribe a treatment plan. Depending on your symptoms, an MRI will scan a specific portion of your body to diagnose: Tumors. Heart damage.
high cost and the need for shielding from the magnetic signals c. can only view metabolically active tissues and inadequate availability of equipment d. release of radiation and the need for a patient to be confined to metal tube for up to 30 minutes. An MRI is expensive and somewhat uncomfortable for the person.