New study demonstrates potential for improving glaucoma diagnosis across Europe

According to Pfizer, newly published results from the European Optic Disc Assessment Trial (EODAT) reveal the accuracy of glaucoma diagnosis can be improved when patients' optic discs are assessed using common imaging devices, and suggests that post-graduate training courses in optic disc assessment would improve glaucoma care.¹ Glaucoma is one of the leading causes of irreversible blindness worldwide. ² Approximately 50% of all glaucoma cases remain undiagnosed. ³

The results echo the European Glaucoma Society's (EGS) recommendation for extended ophthalmologists' training in optic disc assessment to increase early diagnosis and improve glaucoma care in Europe. ³ Earlier diagnosis and treatment can help to reduce the impact of disease progression, and hence the physical and financial costs associated with increasing disease severity. ⁴

EODAT was supported by Pfizer Ltd with an investigator-initiated research grant. The study assessed the diagnostic abilities of 243 ophthalmologists from eleven countries across Europe. ¹ The accuracy of their assessment was compared with that of two specialist imaging devices, the GDx with variable corneal compensation (VCC) and the Heidelberg Retina Tomograph (HRT). One hundred and ten optic disc photographs were evaluated in total. ¹ The ophthalmologists made the correct diagnosis in 80.5% of all optic discs, whilst the GDx VCC and HRT accurately classified 93.2% and 89.8% of the eyes, respectively. ¹ These results indicate that imaging technologies can be used as tools to complement ophthalmologists’ diagnoses, especially in patients with mild to moderate glaucoma, where optic disc damage is harder to recognise.

According to the trial's lead investigator Dr Nicolaas Reus of The Rotterdam Eye Hospital: “Glaucoma is a leading cause of blindness in the developed world, and late diagnosis can lead to irreversible damage to the optic nerve and loss of sight. The imaging devices in this trial had a high diagnostic accuracy and should therefore be used to support clinical assessment and improve early detection of this debilitating condition across Europe. Importantly, the progression of glaucoma can be slowed with early and accurate diagnosis if followed up with appropriate treatments to reduce intraocular pressure.”

As indicated by the high variability in accuracy of the ophthalmologists' optic disc assessments, tackling the increasing burden of glaucoma on healthcare systems in Europe requires widespread and improved training. ¹

Mr Clive Migdal, President of the EGS reinforces the importance of education. He says: “Glaucoma is a devastating disease for so many Europeans and has a negative impact on their quality of life if it is not detected in its early stages and treated appropriately. Crucially, the results from this important study highlight the need for further training to further improve the rates of early diagnosis and alleviate patients’ potential suffering. As stated in the 2008 edition of the EGS Guidelines, a diagnosis should never be based solely on imaging devices, as these are unable to compete with a clinician's many years of training and expertise.”

References

1. N.J. Reus, H.G. Lemij, D.F. Garway-Heath, et al. Ophthalmology.Available at http://www.ophsource.org/periodicals/ophtha/inpress. Accessed 05 January 2010.

2. World Health Organization. Bulletin of the World Health Organization. In Focus, Nov. 1 2004. Available at http://www.who.int/bulletin/volumes/82/11/en/itmb.pdf" Accessed 03 November 2009.

3. European Glaucoma Society. Terminology and Guidelines for Glaucoma (3rd edition). 2008.

4. C.E. Traverso, J.G. Walt, S.P. Kelly et al. Br J Ophthalmol. 2005;89;1245-1249.