OBJECTIVETo estimate the incidence of diabetic retinopathy in relation to retinopathy grade at first examination and other prognostic characteristics.RESEARCH DESIGN AND METHODSThis was a dynamic cohort study of 20,686 people with type 2 diabetes who had annual retinal photography up to 14 times between 1990 and 2006. Cumulative and annual incidence rates were estimated using life tables, and risk factors for progression were identified using Cox regression analysis.RESULTSOf 20,686 patients without proliferative diabetic retinopathy (PDR) or sight-threatening maculopathy at their first retinal examination (baseline), 16,444 (79%) did not have retinopathy, 3,632 (18%) had nonproliferative retinopathy, and 610 (2.9%) had preproliferative retinopathy. After 5 years, few patients without retinopathy at baseline developed preproliferative retinopathy (cumulative incidence 4.0%), sight-threatening maculopathy (0.59%), or PDR (0.68%); after 10 years, the respective cumulative incidences were 16.4, 1.2, and 1.5%. Among those with nonproliferative (background) retinopathy at baseline, after 1 year 23% developed preproliferative retinopathy, 5.2% developed maculopathy, and 6.1% developed PDR; after 10 years, the respective cumulative incidences were 53, 9.6, and 11%. Patients with nonproliferative retinopathy at baseline were five times more likely to develop preproliferative, PDR, or maculopathy than those without retinopathy at baseline (adjusted hazard ratio 5.0 [95% CI 4.4–5.6]).CONCLUSIONSFew patients without diabetic retinopathy at the initial screening examination developed preproliferative retinopathy, PDR, or sight-threatening maculopathy after 5–10 years of follow-up. Screening intervals longer than a year may be appropriate for such patients.

Over time the risk of late diagnosis of STDR decreased, possibly attributable to earlier diagnosis of less severe retinopathy, decreasing risk factors and systematic screening. Screening intervals of up to 24 months should be considered for lower risk patients.

Purpose To directly compare the per-operative safety and efficacy of the 20-and 23-gauge vitrectomy systems as well as day 1 intraocular pressure (IOP). Methods Data were collected on 50 consecutive vitrectomy cases performed using the 20-gauge system and 23-gauge sutureless vitrectomy. All surgeries were carried out by one surgeon (RLB) at a single centre. Data collected prospectively included indication for surgery, iatrogenic retinal tears, and operating times. Results Most common indications for surgery were macular hole, rhegmatogenous retinal detachment, diabetic vitreous haemorrhage (no tractional retinal detachment), and macular pucker. Intraocular tamponade with air, sulphur hexafluoride (SF6), hexafluoroethane (C2F6) or octafluoropropane (C3F8), or silicone oil was used in 25 patients in the 20-gauge group and 46 patients in the 23-gauge group. One scleral port required suture in patients who underwent 23-gauge vitrectomy (0.67%). Every 20-gauge patient had all the three ports sutured. The mean first day IOP was 22.88 mm Hg in the 20-gauge vs 17.58 mm Hg in the 23-gauge (Po0.001). Four patients in the 20-gauge group had an IOP 440 mm Hg compared to none in the 23-gauge group. In contrast, four patients had postoperative hypotony in the 23-gauge group compared to none in the 20-gauge group. The mean operating time for all the 50 cases in each group was 39.4 (20 gauge) vs 29 min (23 gauge) Po0.001. Conclusion Our study indicates less risk of considerably raised IOPs and reduced surgical operating time with the 23-gauge system. Additional advantages observed included faster wound healing, diminished conjunctival scarring, improved patient comfort, and decreased postoperative inflammation.

The PVS may underestimate children's refractive error.