Tuesday, September 7, 2010

MRI Head Scan


MRI Head Scan
MRI (magnetic resonance imaging) is an imaging technique used to get cross-sectional images using strong magnetic field and radio waves (radio frequency pulses) instead of X-rays.  

    In MRI scanning, patients are placed inside a very large and strong magnet, so that all the protons in the atoms of the patient's body can be aligned to a magnetic field. Then, radio waves (called radio frequency pulses) are directed at the protons -- i.e., the nuclei of hydrogen atoms -- to excite the protons. Once the radio waves are stopped, excited atoms emit radio signals received by an antenna (i.e., a surface coil in the MRI machine), which are then measured and processed to form an image using a computer.  
 
   Head MRI provides detailed images of the brain, meninges, inner ear, and eye. MRI can distinguish brain gray matter from white matter, and find small tumors in the brain stem, inner ear, and eyes.

Types of head MRI:
   1. Brain MRI
   2. Sellar MRI -- evaluates pituitary gland
   3. Head and Neck MRI
   4. Orbit MRI
   5. Temporal MRI -- evaluates the inner ear

Advantages Of MRI Scan


  • Provides cross-sectional images in any anatomical plane (upper to lower, right to left, front to back, oblique).




  • Provides clear, detailed images of various soft tissues, such as gray and white matter of the brain, meninges, nerves, inner ear, eyes, blood vessels, temporomandibular joints, tumors, and fluids.




  • It is excellent in evaluating tumors of the brain, meninges, pituitary gland, and vascular or brain stem abnormality.




  • No radiation




  • Compared to the iodine-based contrast medium in X-ray or CAT scan, MRI dye is relatively safe. 





  •  Condition


  • To detect and evaluate tumors of the brain, head, and face




  • In cases involving stroke




  • Chronic neurological disorders such as multiple sclerosis




  • Dementia




  • Seizure




  • When vascular disease is suspected, in problems of the pituitary gland, and with inner ear abnormalities and complaints.   





  • MRI Brain and Head Neck   


  • Brain MRI



    1. Brain tumors -- including meningiomas, posterior fossa tumors, and acoustic neuromas
    2. Metastases, lymphoma
    3. Pituitary tumor or lesion
    4. Infections -- cerebritis, meningitis, brain abscess, toxoplasmosis
    5. Stroke -- cerebral infarction
    6. Vascular diseases -- cerebral aneurysms, arteriovenous malformations, sagittal sinus thrombosis
    7. Neurological disorders -- multiple sclerosis, multifocal leukoencephalopathy
    8. Intra-orbital or visual pathway lesions


  • Head-Neck MRI



    1. Head and neck cancer -- staging
    2. Disorders of the thyroid, parathyroid, and salivary glands; abnormalities of the throat, inner ear, and eyes.
    3. Temporomandibular joint dysfunction 
    Procedure

  • You will be asked to lie on the scan table. You will be asked to lie on the scan table. A head coil will be positioned around your head. After proper positioning, the exam table will slide into the center of the magnet.


  • During the scan you will be alone in the exam room, but you can talk to and listen to the technologist using an intercom, who will watch you through a glass window and video camera.




  • During actual scanning, you will hear loud tapping noises, but you are required to remain still until it's done (to get clear pictures).



  • In the event that a contrast medium is needed to make organs and blood vessels stand out, it will be injected into your vein during the exam.




  • The exam usually takes from 15 minutes to an hour and a half.




  • After proper positioning, the exam table will slide into the center of the magnet.




  • During the scan you will be alone in the exam room, but you can talk to and listen to the technologist using an intercom, who will watch you through a glass window and video camera.




  • During actual scanning, you will hear loud tapping noises, but you are required to remain still until it's done (to get clear pictures).




  • In the event that a contrast medium is needed to make organs and blood vessels stand out, it will be injected into your vein during the exam.




  • The exam usually takes from 15 minutes to an hour and a half.





  • 1 comment:

    1. MRI SCAN knee is a surprising change in science I think it is best option for the patient who is affected.

      ReplyDelete