Quick clinical reference for established retinal classifications. Each entry names the published classification, the examination technique, the categories in their published form, brief clinical notes and a documentation example. Where no generally accepted classification exists, this is stated explicitly. All numerical values are taken from the original publications listed at the end; nothing has been added or rounded.
Age-related macular degeneration
AMD – Beckman classification
Classification: Beckman Initiative for Macular Research Classification Committee, Ferris FL 3rd et al., Ophthalmology 2013 (1).
What is assessed: the clinical AMD category of an eye based on the fundus findings, as a basis for risk communication and follow-up intervals.
Examination: dilated fundus examination or color fundus photography. Lesions within two disc diameters of the fovea are assessed in people over 55 years of age.
Categories:
- No apparent aging changes – no drusen and no AMD-typical pigment changes
- Normal aging changes – small drusen only (<63 µm, so-called drupelets), no pigment changes
- Early AMD – medium drusen (≥63 µm to <125 µm), no pigment changes
- Intermediate AMD – large drusen (≥125 µm) and/or AMD-typical pigment changes in the presence of at least medium drusen
- Late AMD – neovascular AMD and/or geographic atrophy
Clinical notes:
- Classification of the eye, not grading of an individual lesion.
- Pigment changes lead to intermediate AMD only when at least medium drusen are present.
- The five-year risk of late AMD rises across the scale by roughly a factor of 100, from around 0.5 % with normal aging changes to around 50 % in the group at the highest intermediate risk.
- Do not confuse this with the AREDS simplified severity scale, which is a risk score.
Documentation example: AMD, intermediate (large drusen in both eyes, pigment changes on the right).
AMD – AREDS simplified severity scale
Classification: AREDS Report No. 18, Ferris FL et al., Arch Ophthalmol 2005 (2).
What is assessed: the five-year risk of developing advanced AMD in at least one eye.
Examination: clinical examination or fundus photography; count risk factors per eye, then add both eyes together.
Scoring:
- 1 risk factor per eye for one or more large drusen (≥125 µm, the width of a large vein at the disc margin)
- 1 risk factor per eye for any pigment change
- If no large drusen are present, medium drusen in both eyes count as 1 risk factor
- Score 0 – about 0.5 % five-year risk
- Score 1 – about 3 %
- Score 2 – about 12 %
- Score 3 – about 25 %
- Score 4 – about 50 %
Clinical notes:
- Risk stratification, not anatomical staging. The score describes the patient, not an individual eye.
- The risks refer to advanced AMD as defined by AREDS.
- An updated version taking reticular pseudodrusen into account has been published as AREDS Report 42 (3).
Documentation example: AREDS simplified score 2 (large drusen in both eyes), estimated five-year risk of advanced AMD around 12 %.
AMD – OCT atrophy, CAM classification
Classification: consensus of the Classification of Atrophy Meetings (CAM); Sadda SR et al., Ophthalmology 2018, Report 3 (4); Guymer RH et al., Ophthalmology 2020, Report 4 (5).
What is assessed: presence and stage of atrophy in AMD on OCT.
Examination: OCT as the reference method; autofluorescence, infrared reflectance and color images as adjuncts.
Terms: cRORA (complete RPE and outer retinal atrophy), iRORA (incomplete RPE and outer retinal atrophy), cORA (complete outer retinal atrophy), iORA (incomplete outer retinal atrophy).
cRORA, all four criteria required:
- A region of hypertransmission at least 250 µm in diameter
- A zone of attenuation or disruption of the RPE at least 250 µm in diameter
- Evidence of overlying photoreceptor degeneration
- No scrolled RPE and no other signs of an RPE tear
iRORA, in the context of drusen:
- A region of signal hypertransmission into the choroid
- A corresponding zone of attenuation or disruption of the RPE
- Evidence of overlying photoreceptor degeneration
- The term is not used in the presence of an RPE tear
Clinical notes:
- iRORA describes changes that frequently precede cRORA; longitudinal data confirm the transition from iRORA to cRORA.
- The 250 µm thresholds apply to cRORA only.
- cORA and iORA describe outer retinal atrophy with the RPE still intact.
Documentation example: cRORA, subfoveal, greatest linear diameter 1.2 mm on OCT.
Diabetic retinopathy
International clinical diabetic retinopathy disease severity scale
Classification: Wilkinson CP et al., Ophthalmology 2003 (6).
What is assessed: clinical severity of diabetic retinopathy in five levels, for screening and communication.
Examination: dilated fundus examination or fundus photography.
Levels:
- No apparent retinopathy – no changes
- Mild NPDR – microaneurysms only
- Moderate NPDR – more than microaneurysms only, but less than severe NPDR
- Severe NPDR – any one of the 4-2-1 criteria and no signs of proliferative retinopathy
- PDR – neovascularization and/or vitreous or preretinal hemorrhage
Clinical notes:
- NPDR = non-proliferative diabetic retinopathy, PDR = proliferative diabetic retinopathy, IRMA = intraretinal microvascular abnormalities.
- The international scale has only five levels. The ETDRS levels are a separate, finer study scale and should not be conflated with it.
Documentation example: moderate NPDR in both eyes, no visible macular edema.
Severe NPDR – the 4-2-1 rule
Classification: international clinical scale, Wilkinson CP et al. 2003 (6).
Criteria, any one of which is sufficient provided there are no signs of proliferative retinopathy:
- More than 20 intraretinal hemorrhages in each of the four quadrants
- Definite venous beading in two or more quadrants
- Prominent IRMA in one or more quadrants
Clinical notes:
- The ETDRS wording differs: severe intraretinal hemorrhages and microaneurysms in each of the four quadrants, definite venous beading in two or more quadrants, moderate IRMA in one or more quadrants.
- Very severe NPDR, defined as two or more of these criteria, comes from the ETDRS context and is not part of the five-level international scale.
- Assess each quadrant individually before applying the rule.
Documentation example: severe NPDR on the right (venous beading in 3 quadrants), no neovascularization.
Proliferative diabetic retinopathy
Classification: international clinical scale, Wilkinson CP et al. 2003 (6); beyond that, descriptive documentation.
What to document:
- Neovascularization of the disc (NVD)
- Neovascularization elsewhere (NVE), with location
- Preretinal hemorrhage
- Vitreous hemorrhage
- Tractional components or retinal detachment, if present
Clinical notes:
- The international scale does not subdivide PDR further; severity is documented descriptively.
- High-risk characteristics is a historical term from the Diabetic Retinopathy Study. The exact quantitative criteria are not reproduced here and should be taken from the original DRS reports. Flagged for medical review.
Documentation example: PDR on the right, NVD about one quarter of a disc area, no vitreous hemorrhage.
Diabetic macular edema
Classification: international clinical diabetic macular edema disease severity scale, Wilkinson CP et al. 2003 (6).
What is assessed: the presence of macular edema and its distance from the center of the macula.
Examination: retinal thickening requires a three-dimensional assessment, best by dilated slit lamp biomicroscopy or stereoscopic fundus photography. Hard exudates are a sign of current or previous edema.
Levels:
- Diabetic macular edema apparently absent – no apparent retinal thickening and no hard exudates in the posterior pole
- Diabetic macular edema apparently present – apparent retinal thickening or hard exudates in the posterior pole
If present:
- Mild – retinal thickening or hard exudates in the posterior pole, but distant from the center of the macula
- Moderate – retinal thickening or hard exudates approaching the center of the macula but not involving it
- Severe – retinal thickening or hard exudates involving the center of the macula
Clinical notes:
- The modern OCT terms center-involving and non-center-involving describe OCT findings and are not formally identical to mild, moderate and severe. Do not equate them automatically.
- Document central retinal thickness separately, stating the device.
Documentation example: macular edema present, center-involving, central retinal thickness 412 µm (Spectralis).
Hypertensive retinopathy
Simplified classification according to Wong and Mitchell
Classification: Wong TY, Mitchell P, N Engl J Med 2004 (7).
What is assessed: retinal signs of arterial hypertension in a clinically workable grading.
Examination: dilated fundus examination or fundus photography, interpreted in the clinical context of hypertension.
Grades:
- None – no detectable signs
- Mild – generalized arteriolar narrowing, focal arteriolar narrowing, arteriovenous nicking, arteriolar wall opacification (copper wiring) or a combination of these signs
- Moderate – retinal hemorrhages (blot, dot or flame-shaped), microaneurysms, cotton wool spots, hard exudates or a combination of these signs
- Malignant – signs of moderate retinopathy plus optic disc swelling
Clinical notes:
- The highest level is called malignant in the original publication; severe is a colloquial substitution.
- Before grading as malignant, other causes of optic disc swelling, in particular anterior ischemic optic neuropathy, must be excluded.
- The signs of the moderate level are not specific to hypertension and also occur in diabetes and vein occlusions.
Documentation example: hypertensive retinopathy, moderate (cotton wool spots and blot hemorrhages in both eyes), no optic disc swelling.
Keith-Wagener-Barker, historical
Classification: Keith NM, Wagener HP, Barker NW, Am J Med Sci 1939 (8). Historical reference, still frequently cited.
Grades as commonly reproduced:
- Grade I – mild generalized arteriolar narrowing or sclerosis
- Grade II – definite focal narrowing and arteriovenous crossing changes, moderate to marked arteriolar sclerosis, increased arteriolar light reflex
- Grade III – in addition, retinal hemorrhages, exudates and cotton wool spots
- Grade IV – severe grade III plus disc edema
Clinical notes:
- The distinction between the early grades reproduces poorly, which is why the simplified classification is preferred clinically.
- The wording comes from later reproductions; the original 1939 text was not directly accessible.
Vitreous and vitreomacular interface
Posterior vitreous detachment – OCT staging
Classification: Uchino E, Uemura A, Ohba N, Arch Ophthalmol 2001 (9).
What is assessed: the stage of age-related posterior vitreous detachment at the posterior pole on OCT.
Examination: OCT of the vitreoretinal interface, supplemented by biomicroscopy.
Stages:
- Stage 0 – no vitreous detachment
- Stage 1 – incomplete perifoveal detachment in up to three quadrants
- Stage 2 – incomplete perifoveal detachment in all quadrants, with residual attachment at the fovea and the optic disc
- Stage 3 – incomplete detachment over the posterior pole, with residual attachment at the optic disc
- Stage 4 – complete detachment, detectable biomicroscopically, not depictable on the OCT device generation of the time
Clinical notes:
- Detachment usually begins in the superior quadrant.
- Stages 1 to 3 are as a rule not detectable biomicroscopically.
- Stage 4 was defined in 2001 using time-domain OCT; modern devices often depict a complete detachment directly.
- An OCT stage is not equivalent to the clinical diagnosis of a complete vitreous detachment with a Weiss ring.
Documentation example: PVD stage 2 (Uchino), attachment at the fovea and the optic disc.
Vitreomacular adhesion – IVTS
Classification: International Vitreomacular Traction Study Group, Duker JS et al., Ophthalmology 2013 (10).
Definition: perifoveal vitreous detachment with residual vitreomacular attachment and unchanged foveal morphology.
Examination: OCT through the fovea; measure the width of the residual attachment.
Subdivision:
- Focal – attachment 1500 µm or less
- Broad – attachment more than 1500 µm
- Isolated – without further macular pathology
- Concurrent – together with another macular disease
Clinical notes:
- VMA is an OCT finding of normal vitreous aging, not a disease. As soon as foveal morphology changes, it is a VMT.
Documentation example: VMA, focal (900 µm), isolated, right eye.
Vitreomacular traction – IVTS
Classification: IVTS Group, Duker JS et al. 2013 (10).
Definition: anomalous posterior vitreous detachment with anatomical distortion of the fovea; pseudocysts, macular schisis, cystoid macular edema and subretinal fluid are possible.
Subdivision:
- Focal – attachment 1500 µm or less
- Broad – attachment more than 1500 µm
- Isolated or concurrent, as for VMA
Clinical notes:
- The difference from VMA is the anatomical change of the fovea, not the width of the attachment.
- Broad VMT is frequently associated with an epiretinal membrane.
Documentation example: VMT, focal (620 µm), with foveal pseudocysts, left eye.
Full-thickness macular hole – IVTS
Classification: IVTS Group, Duker JS et al. 2013 (10).
Definition: a foveal lesion with interruption of all retinal layers from the internal limiting membrane to the retinal pigment epithelium.
Examination: OCT; the minimum linear diameter is measured, the narrowest horizontal width of the hole, usually in the mid-retina.
Classification along three axes:
- Size – small (≤250 µm), medium (>250 µm to ≤400 µm), large (>400 µm)
- Cause – primary (due to vitreous traction) or secondary (a direct consequence of other pathology)
- Vitreous status – with or without VMT
Clinical notes:
- Always state which diameter was measured; base diameter and apical diameter are not interchangeable with the minimum linear diameter.
- Lamellar macular hole and macular pseudohole are separate entities. For the lamellar hole, the consensus of Hubschman et al. 2020 is authoritative today.
Documentation example: primary full-thickness macular hole, small (218 µm minimum linear diameter), with VMT, right eye.
Epiretinal membrane – OCT staging according to Govetto
Classification: Govetto A et al., Am J Ophthalmol 2017 (11).
What is assessed: OCT severity of epiretinal membranes based on foveal architecture and ectopic inner foveal layers (EIFL).
Examination: spectral-domain OCT through the fovea.
Stages:
- Stage 1 – mild, thin membrane; foveal depression present
- Stage 2 – widening of the outer nuclear layer and loss of the foveal depression
- Stage 3 – continuous ectopic inner foveal layers across the entire fovea; all retinal layers still clearly distinguishable
- Stage 4 – thick membrane with continuous ectopic inner foveal layers and disrupted lamination
Clinical notes:
- Visual acuity decreases continuously from stage 1 to stage 4.
- What distinguishes stages 3 and 4 is the presence of continuous EIFL, not membrane thickness.
Documentation example: ERM Govetto stage 3, EIFL present, central retinal thickness 480 µm.
Further reading
Sources and scientific publications
1. Ferris FL 3rd, Wilkinson CP, Bird A, et al. Clinical classification of age-related macular degeneration. Ophthalmology. 2013;120(4):844–851. PubMed
2. Ferris FL, Davis MD, Clemons TE, et al. A simplified severity scale for age-related macular degeneration: AREDS Report No. 18. Arch Ophthalmol. 2005;123(11):1570–1574. PubMed
3. Age-Related Eye Disease Study Research Group. An updated simplified severity scale for age-related macular degeneration incorporating reticular pseudodrusen: AREDS Report Number 42. Ophthalmology. 2024. Link
4. Sadda SR, Guymer R, Holz FG, et al. Consensus definition for atrophy associated with age-related macular degeneration on OCT: Classification of Atrophy Report 3. Ophthalmology. 2018;125(4):537–548. PubMed
5. Guymer RH, Rosenfeld PJ, Curcio CA, et al. Incomplete retinal pigment epithelial and outer retinal atrophy in age-related macular degeneration: Classification of Atrophy Meeting Report 4. Ophthalmology. 2020;127(3):394–409. PubMed
6. Wilkinson CP, Ferris FL 3rd, Klein RE, et al. Proposed international clinical diabetic retinopathy and diabetic macular edema disease severity scales. Ophthalmology. 2003;110(9):1677–1682. PubMed
7. Wong TY, Mitchell P. Hypertensive retinopathy. N Engl J Med. 2004;351(22):2310–2317. PubMed
8. Keith NM, Wagener HP, Barker NW. Some different types of essential hypertension: their course and prognosis. Am J Med Sci. 1939;197:332–343. Historical reference; grades according to later reproductions.
9. Uchino E, Uemura A, Ohba N. Initial stages of posterior vitreous detachment in healthy eyes of older persons evaluated by optical coherence tomography. Arch Ophthalmol. 2001;119(10):1475–1479. PubMed
10. Duker JS, Kaiser PK, Binder S, et al. The International Vitreomacular Traction Study Group classification of vitreomacular adhesion, traction, and macular hole. Ophthalmology. 2013;120(12):2611–2619. PubMed
11. Govetto A, Lalane RA 3rd, Sarraf D, et al. Insights into epiretinal membranes: presence of ectopic inner foveal layers and a new optical coherence tomography staging scheme. Am J Ophthalmol. 2017;175:99–113. PubMed
