Early Laser Treatment for Diabetic Eye Disease in China : A Pilot Randomized Trial

Inclusion Criteria: * Adults aged \>= 18 years with untreated DR at severe or very severe NPDR stage in either one or both eyes, according to the clinical opinion of the investigator. * Sufficiently clear ocular media to allow visualization of the retina and retinal photography in either eye. * Capable of giving informed consent. Exclusion Criteria: * DR at later stage of retinopathy than severe or very severe (eg, two or more of the 4-2-1 criteria are met) NPDR in either eye, but a patient may be enrolled if one eye has severe or very severe NPDR and the fellow eye has PRP-treated PDR and has been stable after treatment. * Clinically significant macular edema in either eye. * Dense cataracts or other media opacity preventing visualization of the retina in the eye. * History of previous surgical or laser treatment for DR or other retinal conditions in a study eye, including history of anti-VEGF or corticosteroid injection or focal laser for DME within 6 months, or any history of scleral buckle, vitrectomy or other retinal detachment repair. * History of other retinal vascular disorders including CRVO, CRAO, BRVO, BRAO in the study eye. * Previous cataract or glaucoma surgery is specifically allowed if performed ≥ 6 weeks prior to enrollment. * Pregnancy. * Severe renal insufficiency treated with hemodialysis treatment, kidney transplant, pancreatic transplant, and intensive insulin therapy initiated within 4 months. * Nystagmus, unable to cooperate with laser treatment.