The photoacoustic spectroscopic technique for digital imaging could revolutionize the medical world and make a step forward in medicine as dramatic as X-ray once did. Using high ultrasonic resolution and electromagnetic waves together gives deep clear images with high electromagnetic contrast. Because this causes no risk to health it is one of the fastest growing biomedical imaging systems.

This technique has it roots back in the 1880s when Alexander Graham Bell discovered that a thin disc would emit sound if subjected to sunlight which had been mechanically cut. He realized this was also the case when infra red or ultra violet light was used. A graph can then be created plotting the volume of the sound against the light wavelength and this is called the photoacoustic spectrum.

The knowledge was largely forgotten until rediscovered once again at the Bell Laboratories and it was then theoretically described. Light causes a change to matter when it hits it. This small change may be to the temperature or the density of the matter. The light is then modulated and the speed of the changes are increased so that the subject matter is unable to expand and contract which then produces pressure waves which can be measured as sound.

This system can be used on materials in any form. In gases it is capable of detecting the smallest particles of pollutants such as soot in our air. In liquids it is used in blood, blood oxygen, bio-fluids and bio-cells. On solid matter it is particularly useful as the sample can be kept in tact, and does not need to be altered in any way such as dissolving in water. It has however been noted that condensed samples are not as straight forward to work with as gases.

Laser lights have been specially developed with nanosecond pulsed technology and with tune able output wavelength. The former can be used for deep bio tissue imaging for tumours. The latter system is used for scanning several millimetres of bio-tissues and even small animals. Use on living tissue does not cause any known damage.

Earlier work with this technology included measuring blood suspensions such as milk, yeast and glucose. It can also be used to study samples of skin, drug laced tissues, eye lenses and tumours. Studies are now being carried out where this is being used to identify different bacteria types.

When using laser light to identify particles in gases this system can detect minute traces down to one in a trillion. It is always necessary for the material being analyzed to absorb some of this source light to be able to be detected. So this work is limited only by the laser light not having a very broad bandwidth.

Many books and papers are now being written on this work. It is a technique which has so many varied uses there is still a lot to be learned. It is easy to see that photoacoustic spectroscopic technique for digital imaging is going to be a massive breakthrough for medicine.

Author Bio: One of the top digital imaging companies providing modalities specifically designed for preclinical research such as In vivo imaging, in vivo testing micro imaging, Dermatological In Vivo Imaging, high-resolution imaging, scientific digital imaging, digital imaging system.

Category: Computers and Technology
Keywords: science, biology, imaging system, in vivo testing, micro imaging, high-resolution imaging