Table 1

Scottish diabetic retinopathy grading scheme11

Description
Retinopathy
 R0 (no visible retinopathyNo diabetic retinopathy anywhere
 R1 (mild)

  • Background retinopathy BDR—mild

  • The presence of at least any one of the following

    • Dot haemorrhages

    • Microaneurysms

    • Hard exudates

    • Cotton wool spots

    • Blot haemorrhages

    • Superficial/flame shaped haemorrhages

 R2 (observable background)

  • Background diabetic retinopathy BDR—observable

    • Four or more blot haemorrhages in one hemi-field only (Inferior and superior hemi-fields delineated by a line passing through the centre of the fovea and optic disc)

 R3(referable background)

  • Background diabetic retinopathy BDR—referable

  • Any of the following features:

    • Four or more blot haemorrhages in both inferior and superior hemi-fields

    • Venous beading

    • IRMA

 R4 (proliferative)

  • Proliferative diabetic retinopathy PDR

  • Any of the following features:

    • Active new vessels

    • Vitreous haemorrhage

 R6 (inadequate)

  • Not adequately visualised:

    • – Retina not sufficiently visible for assessment

Maculopathy
 M0 (no maculopathy)No features in ≤2 disc diameters from the centre of the fovea sufficient to qualify for M1 or M2 as defined below.
 M1 (observable)

  • Lesions as specified below within a radius of >1 but ≤2 disc diameters the centre of the fovea

    • Any hard exudates

 M2 (referable)

  • Lesions, as specified below, within a radius of ≤1 disc diameter of the centre of the fovea

    • Any blot haemorrhages

    • Any hard exudates