MRI Scans

Magnetic Resonance Imaging (MRI) uses magnetic fields to produce detailed images.  MRI is painless and harmless.  The MRI scanner makes various loud bumping noises as it works - these are normal.  You will be provided with hearing protection during the examination.

For some examinations a contrast agent is required to provide the best information.  This is a safe injection introduced into an arm vein.  This will be discussed in full detail with you at the time of your examination if it is required.

On the examination day

  • Wear your normal clothes - you will be provided with a gown if you need to change for your scan.
  • Arrive in plenty of time for your examination. This will allow for any last minute checks and paper work to be completed (20 minute before your appointment time should be enough).
  • There is no need to stop your medication for the examination and you may eat and drink normally, unless instructed otherwise.
  • Avoid wearing make-up if you are having a scan of your head or face.
  • Complete your health questionnaire and bring it to Nelson Hospital when you attend your appointment.  If you answer YES to any question please contact Nelson Radiology on 548 2745.  MRI direct line 548 2218

After the examination

Your examination will be studied by imaging specialists (Radiologists).  The formal report will be sent to your referring doctor within a few working days of your examination.

How does the scanner work?

Your body is made up of small particles called atoms.  Hydrogen atoms, a major component of water, make up 95% of your body.  Normally the hydrogen atoms within your body spin around at random.  However when you are placed inside a strong magnetic field, the hydrogen atoms naturally line up and spin in the same direction.

When a radiowave is placed through the body, this causes hydrogen atoms to give off a signal.  The scanner detects this signal and, with the aid of a computer, detailed images of the body are produced.

There are no known hazardous side effects associated with this procedure.  There is little information about the safety of MRI in the first three months of pregnancy and an examination during this period is generally avoided.

Is MRI Safe?

Yes.  The magnetic fields are not harmful.  The scanner does not use x-rays.