Surgeons get guiding hand

All in the head: THES reporters investigate the latest advances in brain surgery

More than 300 people with brain tumours, benign head tumours and secondary cancers have benefited from the use of a duo of scanners that create a fuller image of the brain during surgery.

Surgeons rely on pre-operative images of the brain to guide them. But during an operation, fluids shift about, which changes the shape of the brain and renders the images inaccurate.

John Wadley, a surgeon at the National Hospital for Neurology and Neurosurgery in London, and his colleagues teamed up with Philips Medical Systems in Holland and two other collaborators to develop a system that can image the brain better during surgery.

The system combines a CT scanner, which generates images of slices through the brain, with an MRI scanner, which provides images of the brain at work. The CT scanner is useful for imaging the skull before and after a hole is drilled during the operation. The MRI scanner allows surgeons to identify the detail of the brain when they are near the tumour.

Mr Wadley said: "The system has led to a revolution in how we do surgery. Image-guided surgery is the next big thing in neurosurgery, but the problem is the brain changing shape."

To fit inside an operating theatre, the devices are smaller than their pre-operative counterparts. As a result, the images they produce are less sharp. Nevertheless, surgeons are finding them useful. A smaller opening is made in the skull as the location of the tumour can be pinpointed more accurately. This helps to make operations shorter and safer, and allows patients to recover more quickly.

Surgeons at the National Hospital for Neurology and Neurosurgery now use the machine for about a quarter of all brain operations. The manufacturer is continually improving the device and adding new tools on the basis of the surgeons' feedback.

Mr Wadley said: "This is a state-of-the-art machine that is unique in the United Kingdom. It is much better than others on the market."

The machine costs Pounds 100,00 to Pounds 200,000, but Mr Wadley is convinced of its value.

"If hospitals are going to pay for this, it must be useful, practical and value for money. We have proved all those things," he said. Four days in intensive care for a patient whose brain has been accidentally injured during surgery costs about Pounds 4,000. By preventing two such cases a month, the machine would pay for itself within a year or two.

Mr Wadley said that while international work on a robotic endoscope was interesting, surgeons would not use an endoscope at crucial moments. Success depends on the accuracy with which a robotic endoscope can pinpoint the crucial areas of the brain and the location of the tumour. It therefore relies on his work on neuronavigational systems anyway, he argued.