Researchers have wielded beam-shaping techniques to optimise the manufacture of fibre-optic medical instruments using ultrafast lasers.
The work will dramatically bring down the time required to manufacture such devices, helping reduce their cost and increasing their uptake.
Highly innovative thin and flexible optical devices have shown great promise for the future diagnosis and treatment of a range of conditions. The devices, however, require complex systems of micro-optic lenses, mirrors, and prisms – like a microscope – at their end (distal-end microsystems). These systems have the potential to transform the delivery of procedures such as keyhole surgeries and biopsies.
However, manufacturing the complex end of each device has, up to now, taken hours per device, increasing costs, and limiting up-take.
Now, through wielding beam shaping techniques, researchers at Heriot-Watt University in Edinburgh, UK have dramatically brought down the manufacturing time of such optical systems from hours to just a few minutes.
'Medical device technologies are vital for the detection and treatment of a huge number of diseases and healthcare challenges,’ explained Professor Robert Thomson, who led the team behind the new paper. ‘Increasingly, micro-devices are being developed for minimally invasive measurement and therapy, for example in cancer detection and precision laser surgery. However, up to now, they have been very expensive to produce. Coming up with a medical device innovation is exciting but if it can’t be made commercially, it won’t be used in hospitals and clinics. To encourage the take-up of state-of-the-art devices, it is vital to provide low-cost and highly repeatable manufacturing solutions.'
In Optics Express, the researchers describe how they overcome certain limitations of ultrafast-laser-induced selective chemical etching – namely long inscription times and widely varying etching selectivity – by employing beam shaping via a spatial light modulator to generate a vortex laser focus with controllable depth-of-focus when processing fused silica.
'We’ve achieved a major manufacturing advance using laser beam shaping techniques,' remarked Thomson. 'This gives us control of the shape of the focal volume, and therefore more efficient use of the available laser pulse energy during manufacture. We’ve overcome a major drawback of using ultrafast laser inscription techniques for manufacturing distal-end-microsystems for fibre-optic medical instruments.'
The results were unveiled as part of a wider report into Heriot-Watt’s five-year £1.3M 4MD Platform grant, funded by the UK’s Engineering and Physical Sciences Research Council (EPSRC).
Professor Duncan Hand from Heriot-Watt University was principal investigator across the 4MD Platform grant which delivered this and 18 other individual projects, supported by a range of medical and industrial partners. Projects included a new technique to sterilise ambulances using ultraviolet light, an ultrasound needle to better position epidurals during labour, and a proof-of-concept study using lasers to overcome existing limitations of conventional neurosurgery for cleaning brain cancer margins.
Professor Hand said: 'Our overarching objective was to use the flexibility of the Platform grant to develop and exploit manufacturing technologies to provide medical device manufacture that is both practical and commercially viable, leading to new and improved healthcare solutions. The 4MD Platform grant has led to £11.3M of follow-on funding for translational research and the development of medical devices, including the creation of the Medical Device Manufacturing Centre.’
Over the period of the 4MD Platform grant, the area of medical device manufacture, along with related research in biomedical and healthcare engineering, has grown to become a strategic strand for Heriot-Watt University, forming the focus of its third strategic theme (along with Robotics and Energy).