OCT for all, and all for OCT
Eye exams can detect more than ocular disease. Is there a place for it in general practice?
Mark Hillen |
What might the future of diagnostics in healthcare look like in 10 or 20 years’ time? If you speak with general practitioners and hospital doctors, some believe that every patient will go through an MRI scanner as a matter of course. I can see how that would make sense; diagnostic algorithms are run, and a report pops up on the future physician’s... future information delivery device. Add in a blood panel, and you would be able to make a large number of diagnoses in little more than the time it takes to run the tests. But MRI doesn’t resolve fine details like microcapilliaries or nerve fiber bundles – in theory, you would need phenomenally powerful superconducting magnets to do that. So we return to the eye.
Eye specialists already diagnose half of all type II diabetes cases. Cardiologists can (and do) refer their patients for fundus imaging to detect pathologies such as arterial hypertension. The presence of hypertensive retinopathy strongly predicts stroke risk (1). RNFL thickness reductions have been associated with both the stage and duration of schizophrenia, as well as decreased cognitive function (2),(3). In terms of both vascular and neurological disease, the eye offers a clear view (cataract notwithstanding), and highly precise measurements can be made, in the case of fundus photographs and OCT scans, in seconds – or, if techniques such as OCT angiography are used, tens of seconds. Add in artificial intelligence image analysis algorithms like those being developed by Alphabet’s Google DeepMind and Verily divisions, and you’ve got access to rapid diagnoses and risk predictions as well.
Cost is always the barrier to widespread adoption of new technologies. But the cost of adoption will fall. My knowledge of the MRI scanner market is not even superficial, but with OCT, we’re already seeing a trend towards smaller, all-in-one, simple-to-use, lower-cost OCT instruments that patients could almost operate by themselves. You can see the endgame – a simple and effective (and perhaps even portable (4)) diagnostic and screening method for multiple diseases. I can see a scenario in the future where my doctor’s appointment begins with an eye scan that takes 30 seconds, giving the GP time to load my records onto a screen and glance at my history, before they ask, “And what can we do for you today?” Perhaps they’ll already know the answer.
Mark Hillen
Editor
- YT Ong et al., “Hypertensive Retinopathy and Risk of Stroke,” Hypertension, 62, 706–711 (2013). PMID: 23940194.
- WW Lee et al., “Retinal nerve fiber layer structure abnormalities in schizophrenia and its relationship to disease state: evidence from optical coherence tomography”, Invest Ophthalmol Vis Sci, 54, 7785–7792 (2013). PMID 24135757.
- F Ko et al., “Retinal nerve fiber layer thinning associated with poor cognitive function among a large cohort, UK Biobank”, Presented at Alzheimer’s Association International Conference; 2016, Toronto, Canada. Abstract: a10202.
- P Keane, A Walsh, “The OCT Exam’s Quantum Leap”, The Ophthalmologist, 26, 20–27 (2016). Available at: top.txp.to/issues/0116/301. Accessed January 19, 2016.
