Coil allows better detection of organ tumours

Medical staff will be better able to detect tumours with clearer images of organs deep inside the body following the development of a dual function magnetic imaging coil.

Internal organs are currently viewed by giving patients an MRI scan using a magnetic coil to produce radiowaves that are pulsed into the body.

These are bounced back by organs and analysed in a process known as spectroscopy to produce detailed images without the use of X-rays or other radiation. However, the deeper within the body the organ, the harder it is to view.

The coil, designed by a team at Oxford University, will provide doctors with detailed images of organs such as the heart, allowing them to gain important biochemical and metabolic insights into cardiac disease without greatly increasing the complexity and cost of the MRI scanner.

To get an image of a deep organ the scanner must be both sensitive and able to produce waves of the same intensity over the entire area being examined. However, more sensitive coils find it harder to produce uniform waves over larger areas.

‘An inhomogeneous RF field is a disaster as far as deep organ MRI is concerned and could result in a grossly uneven and distorted image,’ said team member Dr Paul Cassidy of Oxford’s department of biochemistry. To avoid this, scanners use a phased-coil array consisting of a number of closely packed coils. This requires the system to have a separate RF transmitter coil and an MR scanner with multiple channels to receive the returning signal, making equipment more expensive to build and use.

However the new coil can perform both functions, allowing it to be used in MRI scanners only equipped to use a single coil.

‘For multi-coil elements significant improvements in speed, sensitivity and homogeneity have been made in recent years, but there is the added expense of multiple receiver channels, and a large transmit coil for the MRI system,’ said Cassidy.

‘The coil was designed for a single coil element MRI, and outperformed existing designs in terms of its sensitivity and magnetic field homogeneity,’ he said.

The new system will overcome problems with MRI sensitivity which were under investigation by Cancer Research UK, Nottingham and York Universities and the Rutherford Appleton Laboratory who hope to use hyperpolarisation to improve detection of solid tumours.

This work is now the subject of a patent application, and Isis Innovation, a wholly-owned subsidiary of the University of Oxford, founded to exploit technology developed at the University, now wishes to discuss suitable arrangements with companies interested in developing and using this technology.

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