AN ULTRASENSITIVE infrared camera is the latest weapon in the fight against
breast cancer. The device senses infrared radiation caused by tiny temperature
fluctuations in the skin around tumours, making it particularly useful for early
tumour detection and avoiding the X-ray exposure needed for conventional
mammography.
Developed at NASA鈥檚 Jet Propulsion Laboratory in Pasadena, California, the
camera uses sensors called quantum well infrared photodetectors
(快猫短视频, 17 February 1996, p 23).
These can detect temperature changes as small as 0.015 掳C.
鈥淎nything at room temperature glows at around 8 or 9 micrometres,鈥� says
Sarath Gunapala, who led the team that invented QWIPs. This is about 10 times
the wavelength of red light. Now Omnicorder Technologies of New York is using
the JPL camera to highlight tumours.
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Tumour cells release chemical messengers that tell blood vessels to dilate.
The resulting increased blood flow brings extra oxygen and nutrients to the
growing tumour鈥攁nd also affects skin temperature. 鈥淲e produce an image map
of areas of abnormal behaviour,鈥� says Mark Fauci, Omnicorder鈥檚 president.
Following promising preliminary trials, the technology has been approved by the
US Food and Drug Administration for use in screening programmes.
鈥淭his is an exciting advance,鈥� says Bryan Jones of the Medical Computing
Group at the University of Glamorgan in Wales. 鈥淏ut the jury is still out as to
how effective it will be.鈥�