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From the start of this year primary care trusts throughout England are implementing diabetic screening programmes in accordance with new national standards.
Though there is some delay in certain areas in moving to a camera-based grading system (my own PCT, for example, has postponed the new scheme roll out and maintains the optometrist slit-lamp BIO scheme for the near future) plans are well in place for a unified screening approach in the coming year.
There are many stated objectives for the new screening scheme, first on the list being a minimum reduction of new blindness related to diabetic retinopathy within five years (and a 40 per cent reduction as an achievable standard). Assuming good patient compliance with attendance and a standardised competence among involved screeners, these admirable targets seem perfectly reasonable.
Competence
To ensure competence among screeners (optometrists and others), a Level 3 Certificate in Diabetic Retinopathy Screening has been developed to ensure a minimum level of competence among all screeners. The certificate comprises of several units, some of which optometrists will be exempt from, and full details of the qualification are obtainable from www.nscretinopathy.org.uk or www.drscertificate.org. Maintenance of competency after the initial certificate has been given to individuals will be decided upon locally for each trust.
Retinopathy grading standards
Retinal images are to be graded along familiar categories. Retinopathy (R) is assessed in terms of the following categories:
? Level 0, no retinopathy (R0). This would require routine diabetes care and continued annual screening
? Level 1, background (R1). This would include the appearance of microaneurysms, intra-retinal haemorrhages and exudates (with no evidence of maculopathy as defined below), see Figure 1 for an example. This would again require routine diabetes care and continued annual screening
? Level 2, pre-proliferative (R2). This would include the presence of venous beading, loops or duplication, intra-retinal microvascular abnormalities (IRMA), multiple haemorrhages, and cotton-wool spots (Figures 2 and 3). A minimum outcome would be for 70 per cent to be seen by an ophthalmologist in under 13 weeks, an achievable target being 95 per cent to be seen in this time
? Level 3, proliferative (R3). This would include new vessels either on the disc (Figure 4) or elsewhere (Figure 5), pre-retinal haemorrhage (Figure 6) and pre-retinal fibrosis. Rubeosis iridis falls into this category. As a minimum, 70 per cent should be seen within 1 week, an achievable target should be 95 per cent
? Maculopathy (M1). Evidence of exudates, retinal thickening and microaneurysms or haemorrhages (if associated with a best acuity of 6/12 or less) within one disc diameter of the fovea (Figure 3 and 7). A minimum outcome would be for 70 per cent to be seen by an ophthalmologist in less than 13 weeks, an achievable target being 95 per cent to be seen in this time
? Urgent referral (same day) would be recommended for any sudden loss of vision or an active retinal detachment. Presumably, secondary glaucoma related to angle blockage with rubeosis might also warrant such management.
The involvement of optometrists in such schemes is, in my view, not only important to ensure adequate assessment, especially in cases where poor image capture requires an ophthalmoscopic assessment as well, but to maintain consistency throughout. So, time for another certificate! ?