23 Jan 2004
Optical technologies are gradually finding their way into hospitals and helping clinicians make better diagnoses. Joe McEntee reports from the recent Smart Biomedical Optics Forum in Cambridge, UK, on the role of photonics in medicine.
When Tony Horn goes on the record about next-generation healthcare technologies, his audience tends to pay attention – close attention – to what he has to say. Hardly surprising: as director for the health technology devices research programme in the UK Department of Health, this senior civil servant is instrumental in shaping how the government allocates its multimillion-Euro annual R&D budget for primary/secondary healthcare and emergency services.
Earlier this month, Horn outlined what he called a “personal rather than departmental” vision of optical and imaging technologies that, if commercialized successfully, could transform not only the National Health Service in Britain, but public healthcare worldwide. His presentation - the keynote address at the Smart Biomedical Optics Forum at the University of Cambridge, UK - was notable on two counts.
Firstly, it gave an innovation roadmap for biomedical equipment manufacturers looking for competitive product differentiation and credible growth potential. Secondly, Horn’s hit-list of optical/imaging innovations could provide a useful starting point for R&D funding agencies and investment professionals as and when they revisit their priorities in biomedical optics and instrumentation. The innovations he described ranged across applications as varied as enhanced diagnostics for Alzheimer’s disease to surgical microendoscopy and preventative medicine.
Take Horn’s case study on clinical depression. The statistics are revealing: in the US alone, 19 million people were diagnosed with clinical depression last year. Of those, 6 million were over 65 years but only 40% of this group asked for any help with depression. Meanwhile in the UK, the sharpest increase in suicides was seen in men over 75 years. For doctors, the problems are compounded by the difficulty in determining if clinical depression is a primary cause or a secondary effect (i.e. a result of other clinical disease such as Alzheimer’s onset or complications with stroke recovery).
The task for biomedical equipment makers and the research community is clear: to come up with imaging diagnostics that remove this uncertainty. The aim is faster diagnosis and more appropriate treatment, which should in turn equate to better quality of life for millions of sufferers.
The latest funding grants in the US, for example, are directed towards the use of single-photon emission-computed tomography, positron emission tomography and magnetic resonance imaging as diagnostic tools, and this led Horn to speculate: “Will we end up with an imaging-like helmet that patients put on in a doctor’s surgery to distinguish the primary and secondary causes of depression? Possibly one in four patients visiting a doctor may benefit from such a low-cost, easy-to-interpret technology.”
Other technology challenges on Horn’s list include the development of:
• non-invasive imaging techniques that offer screening options for early-stage Alzheimer’s disease, “where either medication or a vaccine may halt the progression of the disease”;
• a robust imaging tool capable of rapidly distinguishing different types of stroke “in order to provide quicker onset of appropriate treatment and limit subsequent disability for the patient”; and
• accurate diagnosis for osteoporosis (decrease in bone density), probably combining imaging and pathology, and with the sensitivity to detect positive responses to treatment.
The Cambridge conference was hosted by the Smart Optics Faraday Partnership, a government-backed initiative set up to foster technology transfer between the mainstream optics community and all manner of end-user industries. On this score, it was encouraging to see that the optics professionals are making plenty of progress.
The work of Peter Bryanston-Cross and colleagues in the Optical Engineering Laboratory (OEL) at the University of Warwick is a case in point. “The OEL has created a strong interaction between industrial research and the creation of medical ophthalmic instrumentation,” he told the 60-strong audience of biomedical and optical scientists, engineers and health-care practitioners.
More specifically, Bryanston-Cross explained how his team’s optical know-how in fields like aerospace engineering and combustion analysis is now being successfully applied to diagnostic and surgical problems in ophthalmics. The cross-fertilization works on several levels. Take holographic interferometry, for example, a technique pioneered by Warwick scientists and applied extensively by them over the past decade in studies of turbine blades in jet engines.
Now, however, that same approach has been combined with advances in synthetic intelligence (sophisticated signal-processing software for solving complex image connectivity problems) to yield a system for phase-mapping of the eye’s lens. The technique generates maps of stresses across the lens surface, which is useful to clinicians carrying out corrective surgery.
The team is also developing a non-invasive, non-contact “tonometer”, which uses acoustic resonance to measure the intraocular pressure of the eye for the early detection of glaucoma. The device is still an early-stage prototype but Bryanston-Cross said his long-term goal is “to develop a low-cost probe which could be used by mobile medics, small practices and surgeons in the third world”.
Other areas of ophthalmic research at Warwick include the development of new laser cutting tools for eye surgery; fluorescence sensors to test for diabetes; and a low-cost optical headset (Loupe system) designed for use by third-world eye surgeons.
“The combination of increasing computing power and the use of active optical elements is creating many new types of diagnostic ophthalmic instrumentation,” concluded Bryanston-Cross. “The objective is to provide new types of surgical instrumentation and [to assist] in the early diagnosis of eye disease.”
Readers interested in learning more about smart optics can check out IOP Publishing's latest Technology Tracking report, Industrial and Medical Applications of Adaptive Optics. Contact Susan Curtis, Editor, Technology Tracking, for a Table of Contents and the Executive Summary. Email: firstname.lastname@example.org
The Smart Optics Faraday Partnership
The Smart Optics Faraday Partnership is funded by the UK government to promote the development of advanced optics and its exploitation in UK industry. The network, which was founded in 2000, currently comprises more than 70 industrial and 14 academic partners, and has so far facilitated over £11 m of funding in around 20 collaborative research projects. Its core research programme is supported by the research councils, but a variety of other public and private funding sources have also been accessed.
The partnership is run by “Technology Translators” that support each project throughout its lifetime. By surveying the types of technology available within the UK research base, they are able to identify areas where UK industry could benefit from adopting these new technologies or processes. As a result, almost all projects match a particular science or technology to a scientific, commercial or industrial requirement. The network is open to all academic and industrial organizations with a genuine interest in collaboration.
Some of the key research projects now being supported include:
• Optical manipulation and metrology: This project aims to develop and extend high-precision WFS methods for industrial metrology applications, including optical thin films, precision surface manufacture and multiconjugate adaptive optics systems. The wavefront shape will be measured with a precision better than 0.1 microns, which makes WFS techniques a viable tool for high-precision, non-contact metrology.
• Smart ophthalmoscope: The purpose of this project is to develop a technology demonstrator for a handheld, easy-to-operate, non-contact, high-resolution (10 microns) digital ophthalmoscope. The ophthalmoscope will capture retinal images for digital storage, allowing objective diagnosis and providing future reference for opticians and eye clinicians. The key aims of the research are to integrate advanced optomechanics, illumination, image capture and image processing elements into a working system.
• Adaptive optics toolkit: The idea here to develop enabling technology that will transfer adaptive optics from the laboratory into industrial and medical applications. The toolkit will contain all of the core components for building AO systems, including wavefront sensors, deformable mirrors, control systems and software, and these components can either be used separately or as building blocks for a complete AO system.