Battery powered brain scanner

BBC News has an interesting video report on a hand-held device that uses near-infrared light to penetrate the skull and test the cortex for haematomas – a type of potentially dangerous blood clot caused by head injury.

The device is called the InfraScanner and doesn’t create the sort of brain scans you might be used to seeing, but instead is a hand-held device specifically designed to diagnose this specific type of injury.

It uses technology called ‘near infrared spectroscopy‘ that involves rays of near infrared light being beamed into the head.

This light can penetrate through the skull and a few centimetres into the brain.

Some of this light is reflected back and some is absorbed, depending on what the light encounters on its path.

By measuring the light that get reflected back, it’s possible to determine the structure of the underlying material.

The device uses these principles to work out whether the area under the scanner is normal brain tissue or has a bleed in it.

This can be life-saving information and being able to do this on the spot, rather than needing to give someone a full brain scan, would obviously be incredibly useful.

The technology is also being used in a more complex form called Functional Near Infrared Spectroscopy (fNIRS) to look at brain activation during mental tasks, in a similar way to other types of brain imaging.

The advantage with fNIRS, however, is that it doesn’t involve being put into a big tube (like fMRI), injected with radiation (like PET), doesn’t need a shielded room (like MEG) and has better spatial resolution than EEG.

The technology is still relatively new though and it can only look at surface brain structures, but looks like a promising technology, particularly when it can be modified into hand-held diagnostic devices.

There’s a excellent review of its use in brain imaging in a recent scientific paper (if you have access to the journal) and in a freely available article (pdf) from an IEEE engineering magazine.

Link to video report from BBC News.
Link to PubMed abstract of scientific review.
pdf of magazine article on fNIRS.