DIABETES RETINAL SCREENING, GRADING AND MANAGEMENT
GUIDELINES FOR USE IN PACIFIC ISLAND NATIONS
2009
Grading for Diabetic Macular Disease
(retina within 2 disc diameters of the foveola)
Classification and referral guidelines
M1
M4
M2
M3
M4(2)
Macular Field
Chart 1: Diabetic Retinopathy Macular Grading
Macular diagram For clinical purposes the approximate dimensions of the
macula are as follows:

The perimeter of the macula is 2 optic disc diameters (DD) from the

centre (the foveola) ie, a circle with a radius about 2 DD in length (C).

The diameter of the macula is therefore 4 DD, the perimeter of which is
usually situated just within the temporal vascular arcades

DDs are used for measurement because of the variation in optical

magnification and ocular size
Grade
*An accurate assessment of retinal thickening is not possible with
methods such as photoscreening and ophthalmoscopy.
Referral of M2 may be deferred if an ophthalmologist is available to
undertake biomicroscopy as part of the screening assessment
The presence of Clinical Modifiers would also influence referral of
patients in this grade.
#
Visual Acuity will be impaired if there is fluid (oedema) in the
foveola.
M0
Description
No macular disease
Clinical Signs
Outcome
No microaneurysm, haemorrhage or exudate within 2 disc diame- Screen again in 12 months
M1
Minimal
Screen again in 6 months unless Peripheral Diabetic Retinopathy requires
referral to ophthalmologist
M2*
Mild
Microaneurysms and/or haemorrhages within 2 DD of the centre
of the macula
No exudates
No retinal thickening
No reduction in visual acuity
Exudates and/or retinal thickening within 2 DD of the centre of
the macula, but outside 1 DD of the centre
Refer to ophthalmologist
Review by ophthalmologist in less than 2
months
M3
Moderate
Refer to ophthalmologist
Review by ophthalmologist in less than 1 month
M4
Severe
Exudates or retinal thickening within 1DD of the centre of the
macula
Foveola not involved
No reduction in visual acuity
Either
Microaneurysms and/or haemorrhages within 1 DD of the centre
of the macula
Reduction in visual acuity
or
Exudates and/or retinal thickening involving the foveola
Reduction in visual acuity
Urgent referral to ophthalmologist
Review by ophthalmologist in less than 1 week
(preferably on the same
day as screened)
MT
Stable, treated Macular
Disease
Screen again in 12 months unless Peripheral Diabetic Retinopathy requires
Action