The British Contact Lens Association biennial conference has a well-earned reputation on the conference circuit for its relevance to both clinician and academic. It was not surprising, therefore, that the event was chosen as an ideal location to announce the findings from two eagerly anticipated areas of research concerning dry eye disease and myopia intervention, and here we consider the first of these.
DEWS2
Since 2007, clinicians have referred to the findings of the International Dry Eye Workshop when assessing, recording and managing dry eye and related ocular surface disease. The multi-authored international collective of clinicians and researchers, under the support of the Tear Film and Ocular Surface Society (TFOS), managed to pin down a specific clinical definition of dry eye disease which has been widely used ever since and has greatly added to clarity and standardisation of assessment and management of this very common ocular problem. Other groups within the workshop looked at matters such as assessment technique and management options, always making recommendation based on the published evidence base.
And it is this last point in particular which has made a second TFOS DEWS report both necessary and also of particular interest to eye care practitioners. Many studies into dry eye have been published since 2007, new assessment techniques have been introduced or verified and new management options have become available. The new TFOS DEWS2 report should be freely available from the TFOS website soon after the time this issue of Optician goes to press, but BCLA delegates were treated to a glimpse of what was to come under the trusted guidance of internationally renowned, New Zealand-based expat Professor Jennifer Craig.
Prof Craig began by reminding delegates of the key aims of TFOS DEWS2, which were to update the definition, classification and diagnosis of dry eye, critically evaluate the epidemiology, pathophysiology, mechanism, and impact of this disorder, address its management and therapy, and develop recommendations for the design of clinical trials to assess pharmaceutical interventions for dry eye treatment. The study took over two years to complete and involved experts from more than 90 countries – a truly international collaboration.
The first major announcement was a revision of the definition of dry eye disease. The last definition was two sentences long and required some simplification, Prof Craig noted. It also might be better able to distinguish between diagnostic and pathophysiological. The new definition is as follows;
‘Dry eye is a multifactorial disease of the ocular surface characterised by a loss of homeostasis of the tear film, and accompanied by ocular symptoms, in which tear film instability and hyperosmolarity, ocular surface inflammation and damage, and neurosensory abnormalities play etiological roles.’
The inclusion of homeostasis is noteworthy, as is the attempt to include both hyperosmolarity and inflammatory response. It has to be hoped that we now have a definition that is both all-encompassing and also clear enough to help to define one of the more previously nebulous clinical presentations. This, though, is not enough for accurate assessment and when deciding upon a management plan. To aid this process, TFOS DEWS2 has revised the classification of dry eye disease, and now covers the range of disease from aqueous deficient to the fully evaporative.
Prof Craig explained how patients might be categorised;
- With signs and symptoms – other disease must be ruled out.
- With symptoms but no signs – these may be early disease presentations and might benefit from prophylactic intervention and monitoring. Neuropathic pain might be contributory and explain the lack of eye signs.
- Asymptomatic but with signs – these may be detected at aftercare appointments and may exhibit corneal hyposensitivity concurrent with frank signs. Management is indicated.
- No signs, no symptoms – in other words, normal healthy eyes.
Understanding the nature of the disease influences diagnosis and at this point Prof Craig was joined on stage by Professor James Wolffsohn who led the audience through some of the latest thinking in diagnostics. He discussed how TFOS had looked at tests in a number of ways, such as their sensitivity and specificity, and which are robust and easy to perform. A typical approach might include a sequence including;
- Triage questions regarding, for example, comfort, duration, effect of blinking and so on.
- Questionnaire scorings.
- Non-invasive break-up time.
- Osmolarity reading.
- Surface staining assessment, including lissamine green staining.
To bring home to the delegates the usefulness of such a systematic approach, Wolffsohn (a known dry eye sufferer) allowed himself to be assessed on stage by Prof Craig allowing the audience to see on large screens the slit lamp view and test results.
When TFOS DEWS2 is released, the stages to assessment will be clarified and supported by clear videos online showing each technique being performed.
It was next the turn of the redoubtable Professor Lyndon Jones who had been involved in the mammoth task of reviewing the extensive published literature concerning management of dry eye – a body of work some 73% expanded upon from when reviewed in 2007. Prof Jones and his team had graded each study of a treatment from 1 to 3, with 1 the most robust and including randomised controlled trials. This should allow the adoption of the most relevant treatment as appropriate to each stage of the disease.
The group have considered treatments in seven categories including treatments for lids, tear insufficiency and even complementary medicine approaches.
I await full publication of this extensive review eagerly as it covers areas that patients regularly ask advice on. In concluding, Prof Jones emphasised the importance of starting simple then increase in complexity as required for effective treatment. There might be a need for a whole battery of interventions or simply one or two – the stepwise approach is useful but must be flexible.
The next report will cover the myopia intervention.
