Table 2.
Definitions related to DR/DME, adapted from landmark trials
| Condition | Type | Definition |
|---|---|---|
| Diabetic retinopathy | High-risk PDR (DRS) [48] |
High-risk PDR is defined as any 1 of the following: 1. NVD ≥ 1/3 disc area 2. Any NVD with vitreous hemorrhage 3. NVE ≥ 1/2 disc area with vitreous hemorrhage High-risk PDR is also defined as 3 or more of the following high-risk characteristics: 1. Presence of vitreous hemorrhage or pre-retinal hemorrhage 2. Presence of any active neovascularization 3. Location of neovascularization on or within 1 disc diameter of the optic disc 4. NVD > 1/3 disc area or NVE > 1/2 disc area |
| Severe NPDR (DRS) [48] |
Severe NPDR was defined as the presence at least 3 of the following: 1. Cotton wool spots 2. Venous beading 3. IRMA in at least 2 contiguous overlapping photographic fields 4. Moderate to severe retinal hemorrhages and/or MAs |
|
| Macular edema | Diabetic macular edema (DRCRnet) [54] |
1. Center-involved DME: Retinal thickening in the macula that involves the central subfield zone (1 mm in diameter) 2. Non-center-involved DME: Retinal thickening in the macula that does not involve the central subfield zone (1 mm in diameter) |
| Clinically significant macular edema (ETDRS) [55] |
CSME is defined as 1 or more of the following: 1. Retinal thickening at or within 500 μm of the center of the macula 2. Hard exudates at or within 500 μm of the center of the macula, if associated with adjacent retinal thickening 3. A zone or zones of retinal thickening 1 disc area in size, at least part of which is within 1 disc diameter of the center of the macula |
CSME clinically significant macular edema, DME diabetic macular edema, DR diabetic retinopathy, DRCRnet Diabetic Retinopathy Clinical Research net, DRS Diabetic Retinopathy Study, ETDRS Early Treatment of Diabetic Retinopathy Study, IRMA intraretinal microvascular abnormalities, MA microaneurysms, NPDR non-proliferative diabetic retinopathy, NVD new vessels on or within 1 disc diameter of the optic disc, NVE new vessels “elsewhere”, PDR proliferative diabetic retinopathy