Published on 09/07/2024
AVS fluorescein filter being clipped to a slit lamp
  • Aston Vision Sciences was launched in 2020, based on research conducted at Aston University School of Optometry
  • The new clip-on fluorescein filter is for use by optometrists when examining for eye injury, dry eye conditions and contact lens fit.
  • The low-cost filter has a unique colour formula which enables eye clinics to upgrade to gold standard without investing in expensive new equipment.

Aston Vision Sciences (AVS), a spin-out from Aston University’s School of Optometry, has successfully launched its first product to market – a low-cost, specialist filter for optometrists to use when examining patients’ eyes for a range of common condition include injury, foreign bodies, dry eye and contact lens fit.

Optometrists add a yellow dye, called fluorescein, to the eye in the case of injury, which is then examined under blue light illumination. To obtain the best contrast and visibility, the optometrist will use a filter to allow them to fully assess the extent of any injury and determine the best course of treatment.

Most commonly used fluorescein filters are either poor-quality and degrade quickly, or highly expensive, costing more than £300. The AVS fluorescein filter is robust and long lasting and costs a sixth of the price of conventional fluorescein filters. It has a unique colour formula to ensure maximum contrast and definition for optometrists when examining an eye.

The AVS filter can be clipped onto a range of compatible slit lamps to allow for hands-free use. This provides a low-cost option for many eye clinics and hospitals to upgrade their existing equipment to the recommended gold standard without having to invest in expensive new instruments.

The new fluorescein filter was developed by AVS founder Dr Karl Obszanski, during his PhD studies at Aston University, under the supervision of Professor James Wolffsohn, Head of the School of Optometry, and Dr Thomas Drew. Dr Obszanski’s research focused on new diagnosis techniques for common eye conditions. It led him to look at existing diagnosis methods, how well current machines work, and the high cost of many of them.

Dr Obszanski said:

“Many solutions on the market today do not perform as well as they could and this is due to cost and the inability to create just the right colour formula to give best performance. We have cracked this secret recipe and incorporated our custom colour formula into a convenient, low-cost solution.”

Professor Wolfssohn said:

“It is great to see a robust, regulatory approved yellow filter based on our research, become available for all those slit lamp biomicroscopes that don’t have one built in. A yellow filter is vital for optimised viewing of fluorescein on the ocular surface and its spectral transmission needs to be carefully selected.”

Dr Obszanski started the spin-out company to commercialise the low-cost fluorescein filter technology in 2020. AVS now aims to develop original and innovative devices based on intensive market research. The company collaborates and consults with eye care professionals to fully understand their needs and develop simple products to fill those gaps in the market.

Aston Vision Sciences is particularly dedicated to serving less affluent regions globally, where millions of people worldwide suffer from visual impairments and the risk of blindness. In the UK alone, more than 1,000 individuals begin to lose their sight each month, and in more than 85% of these cases, early detection could prevent sight loss. In many less affluent countries, however, limited resources often result in these conditions going unnoticed and untreated in time.

AVS is developing accessible solutions to connect clinicians with patients that are often beyond the reach of conventional care, catching them earlier in their disease journey and giving them the best chance of a healthy recovery.

Dr Obszanski said:

“We have been working extremely hard on our next solutions and I am glad to say that AVS has two exciting products that will be released in the coming months and again share the same core values – to allow clinicians to perform their best through giving them easy-to-use solutions that will enable them to reach more patients and preventing blindness through early intervention. Whether in a care home in the UK or a remote village in the developing world, our next products will have the portability and functionality to conduct common tests and triage patients to get the care they need as early as possible and help prevent blindness for millions of people around the world.”

Notes to editors

About Aston University

For over a century, Aston University’s enduring purpose has been to make our world a better place through education, research and innovation, by enabling our students to succeed in work and life, and by supporting our communities to thrive economically, socially and culturally.

Aston University’s history has been intertwined with the history of Birmingham, a remarkable city that once was the heartland of the Industrial Revolution and the manufacturing powerhouse of the world.

Born out of the First Industrial Revolution, Aston University has a proud and distinct heritage dating back to our formation as the School of Metallurgy in 1875, the first UK College of Technology in 1951, gaining university status by Royal Charter in 1966, and becoming the Guardian University of the Year in 2020.

Building on our outstanding past, we are now defining our place and role in the Fourth Industrial Revolution (and beyond) within a rapidly changing world.

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