MRI scan

What is a MRI scan?

An MRI scanner uses a combination of a strong magnet and radio waves to take images of your body. There are no x-rays involved.

A neuro MRI focuses specifically on the brain, spine, neck, face and central nervous system.

Our scanners

In neuroradiology we have two MRI scanners:

Siemens 3T
Siemens 1.5T

How does an MRI work?

An MRI scanner uses a strong magnetic field and radio waves to create images of tissues, organs and other structures inside the body. It is useful for all sorts of reasons where other tests (such as X-rays) do not give enough information.

In Neuroradiology it is commonly used to get detailed pictures of the brain and spinal cord.

The MRI scanner uses an extremely strong magnet and this can affect some medical implants, so not everyone can be scanned. The radiographers working in MRI will check all patients before they enter the scan room to ensure they are suitable. It is quite usual for an injection of contrast media to be given via a vein in the arm to allow certain structures to be shown more clearly.

MRI provides detailed pictures of the brain and nerve tissues. It is very sensitive in detecting abnormal brain development, bleeding, infection, tumours, inflammation, hormonal disorders and multiple sclerosis.

An MRI scan is generally considered the single best imaging study of the spine as it provides extremely sensitive information about the discs as well as the presence of tumours, infection, demyelination and herniated discs. The spinal cord is also clearly visualised as are the nerve roots and any potential compression of structures. MRI plays an important part in surgical planning and follow up due to its sensitivity and accuracy.

Magnetic resonance angiography is used to generate images of the arteries and veins in the head and neck in order to evaluate them for stenosis (abnormal narrowing), occlusion or aneurysms (vessel dilatations, at risk of rupture). Images are acquired whilst injecting a contrast material into a peripheral vein, to produce detailed images of both blood vessels and surrounding tissues.

Safety

For some people it may be dangerous to go into a MRI scanner

Do you have any of the following?

A pacemaker
Any implants
Metal in your eyes
Any operation requiring clips in your head
Could you be pregnant?

If so, please call us on 0191 2823947 to discuss your scan.

How does MRI work?

The patient lies on a table which is moved so that the part of the body being imaged is inside the large, cylinder-shaped magnet. Radio waves are then sent through the body and the strong magnetic field causes the alignment of particles, called protons which are found naturally within the body, mostly in hydrogen atoms.

Hydrogen, together with oxygen and carbon, make up 99 per cent of the average human body, and therefore almost all the protons found within the body are affected by the strong magnetic field. Once the magnetic field is switched off, the protons begin to lose their alignment, and go back to their original position before the magnetic field was applied.

As they move back into their original positions, they send out radio waves of their own. The scanner picks up these signals and a computer turns them into an image. The image is based on the location and strength of the incoming signals.

Different protons send out different signals, depending on which tissue the proton can be found in. For example, a proton found in bone will emit a very different radio wave signal when compared to a proton found in blood.

These signal differences allow an image to be created and different tissues or structures to be distinguished from one another.