Researchers at UCL (University College London) are developing a portable brain scanner which could help save the lives of premature and newborn babies in intensive care by avoiding to move them to conventional scanning facilities. A current prototype combines the advantages of both magnetic resonance imaging (MRI) and ultrasound. It uses optical tomography to generate images showing how the brain is working and a new generation should be ready by 2008 and such scanners should be commercially available shortly after.
Here are some excerpts of the Engineering and Physical Sciences Research Council (EPSRC) news release about this project.
A prototype of the scanner, called MONSTIR, has been developed by researchers at UCL (University College London) with funding from the Engineering and Physical Sciences Research Council (EPSRC) and the Wellcome Trust. Now, also with EPSRC funding, the team are aiming to reduce the size of the scanner and improve its speed of operation.
A helmet incorporating 32 light detectors and 32 sources of completely safe, low-intensity laser light is placed on the baby’s head. The sources produce short flashes and the detectors measure the amount of light that reaches them through the brain and the time the light takes to travel. A software package also developed with EPSRC funding uses this information to build up a 3D image. This can show which parts of the brain are receiving oxygen, where blood is situated, evidence of brain damage etc.
Below is a diagram showing the different components of this brain scanner with its 32 independent time-resolved detectors operated in parallel (Credit: UCL Dept of Medical Physics & Bioengineering).
The imaging device designed and built at UCL for performing 3D optical tomography consists of 32 parallel detectors which measure the times-of-flight of transmitted photons at two nearinfrared wavelengths simultaneously. The sources are two synchronized fibre lasers (built by IMRA, Inc.) operating at 780 nm and 815 nm, which illuminate the head via a 32-way optical fibre switch. The light transmitted across the tissue is collected by 32 detector fibre bundles, which are coupled to four 8-anode microchannel-plate photomultiplier tubes (MCP-PMTs).
Before working on real babies, the researchers had to build adequate 3D models with realistic geometries and optical properties. And they employed meshes based on a head of a child's doll. You can see below a 3D x-ray CT-scan (left) of the doll's head and a surface mesh generated from the CT-scan (right) (Credit: UCL Dept of Medical Physics & Bioengineering).
You'll find many more details and pictures by reading "Imaging the Neonatal Brain" at UCL.
The new version of this brain scanner will continue to be developed until 2008 at UCL with the help of a grant of about £325,000 from EPSRC for this project named "Optical Tomography of the Neonatal Brain."
Finally, you also might be interested in a previous work published by 'Physics in Medicine and Biology' under the name "Imaging changes in blood volume and oxygenation in the newborn infant brain using three-dimensional optical tomography" (Volume 49, Number 7, April 7, 2004). Here are two links to the abstract and to the full paper (PDF format, 14 pages, 525 KB). The description of the imaging device was extracted from this document.
Sources: Engineering and Physical Sciences Research Council (EPSRC) news release, December 19, 2005; and various web sites
You'll find related stories by following the links below.