MRI scanner

People with suspected neurological conditions such as multiple sclerosis, stroke and epilepsy are getting clearer and earlier diagnoses thanks in part to a new MRI scanning method developed at Imperial College London.

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Quick facts

  • There are over 20 million FLAIR examinations carried out each year, worldwide
  • The FLAIR scanning capability is now built into every single MRI machine built worldwide
  • FLAIR is used routinely in almost all neurological scanning

Magnetic resonance imaging (MRI) technology has had a transformative impact on many areas of clinical medicine and research – allowing doctors to see inside the human body like never before.

An MRI scan involves a patient lying in a strong magnetic field while radio-frequency waves are directed at their body. It takes advantages of the fact that most of the human body is made up of water molecules, consisting of a hydrogen and oxygen atom. The single protons in the hydrogen atoms act like a tiny magnets and interact with the MRI machine in way which can be measured.  Crucially protons in different types of tissue interact differently allowing the differentiation between various internal structures of the body.

With certain modifications to the process, these tissue differences can be emphasised further.  And that’s what a multidisciplinary team at Imperial sought to do.

Collaborative environment

The combination of engineering, physics and clinical imaging expertise in the Robert Steiner Unit at Imperial College’s Hammersmith Hospital campus has provided a unique environment for the development and rapid translation of novel MRI technologies.

This work has led to improvements in MRI hardware and image optimisation. One innovation that has proved particularly successful is Fluid Attenuated Inversion Recovery (FLAIR).

The FLAIR method highlights pathological accumulations of water in the brain - such as in tissue damaged by a stroke or from oedema associated with inflammation. The key point is that FLAIR images provide a very high contrast between healthy and pathological tissues, enabling earlier detection, more reliable diagnosis and better disease management.

FLAIR has also led to more powerful clinical trial designs for the development of medicine for stroke, neuroinflammatory disorders and epilepsy.

Excellence becomes routine

The FLAIR capability is now incorporated as a standard by all manufacturers on their MRI scanners. It is recommended in imaging guidelines and is part of diagnostic criteria used by numerous international organisations including the American College of Radiology.

The commercial impact also has been significant. The global market for MRI systems was estimated to be £4.3 billion in 2010, and is expected to grow to around £6.2 billion by 2015, equivalent to an annual growth of 7.7% a year. MRI systems made a direct value-added contribution to UK GDP of around £54 million (in 2010 prices) with FLAIR is incorporated into all of these new MRI machines.