Healthcare Providers Resource Page

Risk Medical Solutions has developed a risk calculator for sight-threatening diabetic retinopathy (STR), including proliferative diabetic retinopathy (PDR) and clinically significant diabetic macular edema (CSME). The output gives an individualized risk analysis for each patient based on well-established risk factors for STR, including diabetes sub-type, gender, glycosylated hemoglobin (HbA1c), blood pressure, disease duration and presence and severity of any non-proliferative disease (NPDR). The algorithm has been clinically validated in a large Danish diabetes cohort.

Both patients and providers can use the risk calculator. It works well as a guiding tool for patients with diabetes because it shows how each modifiable risk factor (HbA1c and blood pressure) impacts the risk of retinopathy progression, and is well-suited as an educational tool for in-office consultation. Doctors of Optometry can also use the risk calculator as a decision support tool for frequency of eye examinations and communication with other members of the healthcare team.

Below are some additional tools and links to assist eye care providers in delivering high quality, individualized care to their patients with diabetes based on the best available scientific evidence.
  • International Grading Scale for Diabetic Retinopathy*
    Proposed Disease Severity Level Findings Observable With Dilated Ophthalmosco
    No apparent DR No abnormalities
    Mild nonproliferative DR Microaneurysms only
    Moderate nonproliferative DR More than "mild" but less than "severe"
    Severe nonproliferative DR
    (4-2-1 rule)
    Any of the following:
    • 20 or more intraretinal hemorrhages in 4 quadrants
    • Definite venous beading in 2 or more quadrants
    • Prominent IRMA (intra-retinal microvascular abnormalities) in 1 or more quadrants and no neovascularization
    Proliferative DR 1 or more of the following:
    • Definite neovascularization
    • Preretinal or vitreous hemorrhage
    ** patients with Severe NPDR have a 15% chance of developing PDR within the following year per ETDRS Report #18
    ** patients with Very Severe NPDR (2 or more severe NPDR findings) have a 45% chance of developing PDR within the following year per
    ETDRS Report #18
  • International Grading Scale for Diabetic Macular Edema*
    Proposed Disease Severity Level Findings on Dilated Ophthalmoscopy
    DME absent No retinal thickening or hard exudates present in posterior pole
    DME present Some retinal thickening or hard exudates present in posterior pole
    If DME is present, it can be categorized as follows:
    Proposed Disease Severity Level Findings Observable on Dilated Ophthalmoscopy*
    Mild DME Some retinal thickening or hard exudates in posterior pole but distant from the center of
    the macula
    Moderate DME Retinal thickening or hard exudates approaching the center of the macula but not involving the center
    Severe DME Retinal thickening or hard exudates involving the center of the macula
    * Proposed international clinical diabetic retinopathy and diabetic macular edema disease severity scales. Ophthalmology.
    2003 Sep;110(9):1677-82
  • Definition of CSME per ETDRS Report #18 (Arch Ophthalmol 113:1144, 1995)
    1. retinal edema located at or within 500 μm of the center of the macula or
    2. hard exudates at or within 500 μm of the center if associated with thickening of adjacent retina or
    3. a zone of thickening larger than 1 disc area if located within 1 disc diameter of the
      center of the macula
  • Some Key Diabetic Retinopathy Facts
    1. Analysis of data from the most important clinical trials (DCCT, EDIC, UKPDS) shows that each 10% reduction in HbA1c (e.g. from 9.0% to 8.1%) lowers the risk of diabetic retinopathy progression by 43%
    2. Higher incidence of severe diabetic retinopathy and macular edema is associated with male sex, severe diabetic retinopathy, higher glycosylated hemoglobin, proteinuria, higher systolic and diastolic blood pressure, and greater pack-years of smoking
    3. Evidence from DCCT/EDIC suggests that early tight control of diabetes has a delayed protective effect that lowers the risk of developing severe diabetic retinopathy in the future
    4. American Academy of Clinical Endocrinology (AACE) guidelines recommend an HbA1c < 6.5% and blood pressure < 130/80 for most people with diabetes (with exceptions for children, patients with established cardiovascular disease and/or short life expectancy). Target LDL cholesterol for patients with diabetes is < 100 mg/dl, triglycerides < 150 mg/dl, and HDL cholesterol > 40 for men and > 50 for women.
  • Web Resources for Diabetes Education, News, Information and Research
  • Algorithm for management of DR

    NVD = neovascularization of the optic disc VH = vitreous hemorrhage
    NVE = neovascularization elsewhere DME = diabetic macular edema
    NVI = neovascularization of the iris or angle CSME = clinically significant macular edema
    MA = microaneurysm formation IRMA = intraretinal microvascular abnormalities
    Algorithm courtesy of A. Paul Chous, M.A., O.D., FAAO.
    With gratitude to Joseph J. Pizzimenti, O.D., FAAO, Director of Macula Services, NOVA Southeastern University
    College of Optometry.

    These are general guidelines - each patient should be managed individually based on these and other factors,
    according to the provider's professional opinion and current standards of care.
  • Scottish Diabetic Retinopathy Grading Scheme 2007 v1.1
    Retinopathy Description Outcome
    R0
    (no visible retinopathy)
    No diabetic retinopathy anywhere Rescreen 12 months
    R1
    (mild)
    Background diabetic retinopathy BDR - mild The presence of at least one of any of the following features anywhere
    • dot haemorrhages
    • microaneurysms
    • hard exudates
    • cotton wool spots
    • blot haemorrhages
    • superficial/ flame shaped haemorrhages
    Rescreen 12 months
    R2
    (observable background)
    Background diabetic retinopathy BDR - observable Four or more blot haemorrhages (ie ≥AH standard photograph 2a – see below) in one hemi-field only (Inferior and superior hemi-fields delineated by a line passing through the centre of the fovea and optic disc) Rescreen 6 months
    (or refer to ophthalmology if this is not feasible)
    R3
    (referable background)
    Background diabetic retinopathy BDR – referable Any of the following features:
    • Four or more blot haemorrhages (ie ≥AH standard photograph 2a – see below) in both inferior and superior hemi-fields
    • Venous beading (≥AH standard photograph 6a – see below)
    • IRMA (≥AH standard photograph 8a – see below)
    Refer ophthalmology
    These patients may be kept under surveillance and will not necessarily receive immediate laser treatment.
    R4 (proliferative) Proliferative diabetic retinopathy PDR Any of the following features:
    • Active new vessels
    • Vitreous haemorrhage
    Refer ophthalmology
    These patients are likely to receive laser treatment or another intervention.
    R6 (inadequate) Not adequately visualised : Retina not sufficiently visible for assessment Technical failure
    Arrange alternative screening examination. This will be automatic within the screening programme.

    Maculopathy Description Outcome
    M0
    (No maculopathy)
    No features ≤ 2 disc diameters from the centre of the fovea sufficient to qualify for M1 or M2 as defined below. Rescreen 12 months
    M1
    (Observable)
    Lesions as specified below within a radius of > 1 but ≤ 2 disc diameters the centre of the fovea
    • Any hard exudates
    Rescreen 6 months
    (or refer to ophthalmology if this is not feasible)
    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
    Refer ophthalmology
    These patients may be kept under surveillance and will not necessarily receive immediate laser treatment.