An international scale that simplifies the grading of diabetic retinopathy is favoured over an alternative system because it is easier to apply in clinical practice, an Australian working group of experts advises.
Optometrist and diabetes expert Paula Katalinic said that there were two accepted systems for grading diabetic retinopathy.
‘There is the International Clinical Diabetic Retinopathy and Diabetic Macular Oedema Disease Severity Scale—that’s a mouthful—and the Wisconsin System,’ Ms Katalinic said.
‘Despite its long name, the International Scale is a simple, straightforward system that is easier to apply in clinical practice because it doesn’t rely on the use of standard photographs or complicated definitions for clinically significant macular oedema.
‘Determining the level of retinopathy is important because it predicts the likely rate of progression to vision threatening disease,’ she said.
The International Scale (Table) is a key tenet in Optometry Australia’s newly-released Clinical Guideline for examining and managing patients with diabetes.
Optometry Australia established a working group in 2013 to revise the guideline, which the organisation’s national board approved at its meeting on 23 May 2014. The guideline had been revised in 1999 and 2009.
Ms Katalinic was a member of the working group that contributed to the guideline review. She spent nearly four years at the Joslin Diabetes Center in Boston where she ‘lived and breathed diabetes’.
She is now involved in working with the New South Wales state health department to improve visual outcomes for people with diabetic retinopathy and is on the Health Advisory Committee for the Australian Diabetes Council.
Ms Katalinic is also the professional services manager of Optometry NSW/ACT and a principal optometrist at the Centre for Eye Health.
‘The new Optometry Australia guideline reinforces another key aspect of managing patients with diabetic retinopathy—whether mild, moderate or severe—and that is the crucial role of optometrists in a multidisciplinary health-care team,’ Ms Katalinic said.
‘You are part of a team. Share your results with the patient’s endocrinologist and GP, and ask the patient for the results of other medical tests such as their latest glycated haemoglobin. This is crucial because if the patient has poor blood glucose control, kidney disease or high blood pressure, for example, the risk of progression of their diabetic retinopathy is much greater.
‘Evidence shows that both general health and visual outcomes are better for patients when their health-care experts communicate. Educating your patients about the risk diabetes poses to their eyes reinforces the importance of good control of their disease.’
Optometry Australia’s clinical guideline also highlights the necessity of stereoscopic fundus examination with pupil dilation in patients with diabetic retinopathy.
‘Pupil dilation is a mandatory procedure in accordance with NHMRC guidelines and MBS item 10915,’ Ms Katalinic said. ‘A fundus photograph is not an acceptable alternative. You can miss significant retinopathy if you’re relying on retinal imaging alone.
‘As the guideline explains, pupil size, media opacities, camera resolution and the location of retinopathy outside the posterior pole region can also influence the sensitivity of digital photography. It is not equivalent to a comprehensive examination of the retina,’ she said.
Members can download the Clinical Guideline for examining and managing patients with diabetes, from the Optometry Australia website.