Now, device to help doctors see hard to reach body parts

A fibre-optics device as thin as human hair, which could allow doctors to see inside the hardest to reach and delicate human body parts has been developed by scientists, including an Indian-origin professor.

Scientists at the University of St Andrews, led by Dr Tomas Cizmar and Indian-origin Professor Kishan Dholakia developed a technique which for the first time allowed the transmission of accurate images along a single strand of fibre optic cable.

Until now, attempts to use such narrow fibres to transmit images had always resulted in scrambled signals. Cizmar and Dholakia however have found a way to decode the scrambled light to construct a clear and true picture, the 'Daily Mail' reported.
Creating minute medical devices was once the realm of science fiction such as in the 1987 film 'Innerspace'.

Their breakthrough holds out the hope of the development of new, inexpensive and minimally invasive imaging devices andscopes which can 'see' in hard to reach places.
It could be of particular benefit in neuroscience and other branches of medicine and science where the area under study is either delicate or very difficult to reach.
Fibres that can support multiple modes of light normally scatter light and produce random, unpredictable patterns at their output. Ordinarily this is a problem for imaging, as the image is distorted as it travels, and is lost on transmission.

However, scientists discovered that if the randomisation of light within the fibre can be characterised, the way the images are scrambled can be predicted. In turn, the output light can be modulated to reverse the randomisation and reveal the original image.

By careful modulation of the input imaging light field, they were also able to select the depth of focus of the system, circumventing the need for focussing optics and allowing for a dynamic, real-time adjustment of the imaging system.

"Holographic control of randomized light signals is a young but very progressive discipline. It is only a few years since the first experiments but we have already witnessed a number of immensely promising achievements some of them originating in St Andrews," Cizmar said.

"Our new contribution represents a further extension of this branch to the Bio-medical community and we are looking forward to see what a further advancement of these techniques may bring in the future. It is a very exciting time," he said.