13.4  Medical Retina - Diabetes

IVB = Bevacizumab, IVR = Ranibizumab, IVA = Aflibercept, IVTA = Triamcinolone

DCCT [xxxiv]


Strict BSL control in T1DM reduces development and progression of DR, DMO, need for laser, and nephropathy & neuropathy

Hainsworth, D.P., Bebu, I., Aiello, L.P. et al. 2019. Risk Factors for Retinopathy in Type 1 Diabetes: The DCCT/EDIC Study. Diabetes Care 42(5) 875-882.

UKPDS [xxxv]


Strict BSL control in T2DM reduces DR progression and microvascular complications

Tight blood pressure control reduces progression of DR

FIELD [xxxvi,xxxvii]


Fenofibrate in T2DM reduces need for laser treatment for ALL DR (unrelated to concentration of plasma lipids)

ACCORD [xxxviii,xxxix]


Intensive BSL and lipid control reduced rate of progression of retinopathy in those with high risk of cardiovascular disease

Intensive BSL control caused more systemic hypoglycaemic episodes

ETDRS [xl]

Early Treatment Diabetic Retinopathy Study

Macular laser for “CSMO” reduces moderate visual loss

CSMO = 1. DMO within 500 microns of the fovea, 2. Hard exudate within 500 microns of the fovea associated with DMO, 3. Disc area of DMO within disc diameter of the fovea

PRP for high risk PDR; severe NPDR defined (any of: 4 quadrants retinal haemorrhages, 2 quadrants venous beading, 1 IRMA)

PRP can worsen DMO in the short-term

DRS [xli]

Diabetic Retinopathy Study

PRP for high risk PDR halves risk of severe VA loss, causes macular oedema

DRVS [xlii]

Diabetic Retinopathy Vitrectomy Study

“Early” (1 - 6 months) vitrectomy useful for severe VH

Protocol I [xliii,xliv]

Focal/grid laser vs IVR + prompt laser vs IVR + deferred laser vs IVTA + prompt laser

IVR + prompt or deferred laser better than focal/grid laser alone

IVTA + prompt laser better than focal/grid laser alone in pseudophakes but causes IOP rise

5 Year results: IVR + prompt laser no better than IVR + deferred laser

Bressler, S.B., Glassman, A.R., Almukhtar, T. et al. 2016. Five-Year Outcomes of Ranibizumab With Prompt or Deferred Laser Versus Laser or Triamcinolone Plus Deferred Ranibizumab for Diabetic Macular Edema. American Journal of Ophthalmology 164 57-68.

Elman, M.J., Ayala, A., Bressler, N.M. et al. 2015. Intravitreal Ranibizumab for Diabetic Macular Edema with Prompt versus Deferred Laser Treatment: 5-Year Randomized Trial Results. Ophthalmology (Rochester, Minn) 122(2) 375-381.

Protocol T [xlv]


IVR = IVA = IVB for DMO when VA ≥ 6/12 (20/40)

At 1 year: IVA superior for DMO when VA ≤ 6/15 (20/50)

At 2 years: IVA no longer superior for DMO when VA ≤ 6/15 (20/50)

Diabetic Retinopathy Clinical Research, N., Wells, J.A., Glassman, A.R. et al. 2015. Aflibercept, bevacizumab, or ranibizumab for diabetic macular edema. The New England Journal of Medicine 372(13) 1193-1203.

Protocol S [xlvi]

IVR monthly vs PRP for PDR

At 2 years: IVR non-inferior to PRP for PDR.

IVR had less DMO, vitrectomy rates and visual field loss

CLARITY [xlvii]

IVA vs. PRP for PDR without baseline DMO

At 1 year: IVA non-inferior and superior to PRP for PDR

IVA had less DMO, vitreous haemorrhage rates and visual field loss

Protocol V [xlvii]

IVA vs. Focal laser (with rescue IVA vs. Observation (with rescue IVA) for DMO with “very good” vision

At 2 years: Initial observation or focal laser at baseline (with rescue IVA if required) non-inferior to IVA only for DMO with “very good” initial vision (≥ 6/7.5, 20/25)

RESTORE [xlix]

IVR vs. IVR/laser vs laser

IVR or IVR/laser better than laser alone for DMO

Mitchell, P., Bandello, F., Schmidt-Erfurth, U. et al. 2011. The RESTORE study: ranibizumab monotherapy or combined with laser versus laser monotherapy for diabetic macular edema. Ophthalmology 118(4) 615-625



IVR effective for DMO

Nguyen, Q.D., Brown, D.M., Marcus, D.M. et al. 2012. Ranibizumab for Diabetic Macular Edema: Results from 2 Phase III Randomized Trials: RISE and RIDE. Ophthalmology 119(4) 789-801.



IVA effective for DMO

Heier, J.S., Korobelnik, J.F., Brown, D.M. et al. 2016. Intravitreal Aflibercept for Diabetic Macular Edema: 148-Week Results from the VISTA and VIVID Studies. Ophthalmology 123(11) 2376-2385.

BOLT [lii]

IVB vs. more laser (when laser failed)

IVB effective for DMO

MEAD [liii]

Dexamethasone implant vs laser

Dexamethasone intravitreal implant effective for DMO, but causes cataract and glaucoma

Boyer, D.S., Yoon, Y.H., Belfort, R., Jr. et al. 2014. Three-year, randomized, sham-controlled trial of dexamethasone intravitreal implant in patients with diabetic macular edema. Ophthalmology 121(10) 1904-1914.

A comprehensive list of up to date DRCR.net studies is available on their website: [liv]

DRCR.net. 2020. DRCR.net Publications [online]: JAEB Center for Health Reserach. Available at: https://public.jaeb.org/drcrnet/pubs [Accessed 8th June 2020].


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