Park et al evaluated the prevalence of and risk factors for diabetic retinopathy (DR) in Koreans with type II diabetes (400 male, 296 female; aged 30–65 years) enrolled in the Seoul Metro-City Diabetes Prevention Program (SMC-DPP). The overall prevalence of any type of DR was 18.7%. In addition to traditional risk factors (duration of diabetes, serum HbA1c, mean arterial pressure, serum total cholesterol and serum triglycerides) insulin resistance was associated with an increased risk of DR. (see page 151)

Gill et al compared the efficacy and safety of a two-quadrant technique that allows the use of a higher volume of local anaesthetic in 54 patients undergoing vitrectomy. Control group (27) received a standard 5 ml single inferonasal sub-Tenon injection of a 50:50 mixture of 2% lidocaine and 0.5% bupivacaine with 150 IU hyaluronidase and...

To evaluate the prevalence of and risk factors for diabetic retinopathy (DR) in Koreans with type II diabetes.

Subjects (400 male, 296 female) aged 30–65 years (mean 55.3 years) with hyperglycaemia (fasting plasma glucose ≥7.0 mmol/ml) or known diabetes (mean±SD duration 6.36±5.73 years) were enrolled in the Seoul Metro-City Diabetes Prevention Program (SMC-DPP) from September 2008 to September 2009. The severity of DR was diagnosed by grading fundus photographs taken from five standard fields per eye and categorised following the Early Treatment of Diabetic Retinopathy Study grading protocol. All participants underwent routine clinical and laboratory examinations to evaluate risk factors for DR.

The overall prevalence of any type of DR was 18.7%. Logistic regression analyses showed that the following factors were significantly associated with DR after adjustment for age and gender, duration of diabetes, serum glycated haemoglobin A1c (HbA1c), mean arterial pressure, serum total cholesterol and serum triglycerides: duration of diabetes (OR 1.14, 95% CI 1.10 to 1.18, for 1 year increase), HbA1c (OR 1.49, 95% CI 1.20 to 1.85, for 1% increase), serum concentration of insulin (OR 0.87, 95% CI 0.81 to 0.94, for 1 μIU/ml increase), homoeostasis model assessment of insulin resistance (OR 0.06, 95% CI 0.01 to 0.29, for 10 unit increase), and presence of macroalbuminuria (OR 5.14, 95% CI 1.45 to 18.20, albumin to creatinine ratio >300 mg/g).

In addition to traditional risk factors, insulin resistance was associated with an increased risk of DR in Koreans with type 2 diabetes.

There are few published data on the prevalence of diabetic retinopathy in sub-Saharan Africa. We report the prevalence of all grades of retinopathy and associations with systemic parameters in patients attending a secondary care diabetes clinic in Blantyre, Malawi.

Cross-sectional study of all patients attending for diabetes care in a hospital setting. Clinical examination and biochemical testing was performed to assess visual acuity (VA), grade of retinopathy (slit lamp biomicroscopy), microvascular complications, glycaemic control, hypertension and HIV status. Sight-threatening diabetic retinopathy (STDR) was defined as moderate preproliferative retinopathy or worse, circinate maculopathy or exudates within one disc diameter of the foveal centre or clinically significant macular oedema.

In patients with type 2 diabetes (n=249) the prevalence (95% CI) of any retinopathy, STDR and proliferative diabetic retinopathy (PDR) was 32.5% (26.7 to 38.3%), 19.7% (14.7 to 24.6%) and 4.8% (2.2 to 7.5%), respectively. The presence of STDR was associated with albuminuria (OR 2.6; p=0.02), the presence of neuropathy (OR 3.4; p=0.005) and insulin use (OR 5.3; p=0.0004), but not with HIV status. In patients with type 1 diabetes (n= 32), the prevalence of any retinopathy, STDR and PDR was 28.1% (12.5 to 43.7%), 18.8% (5.2 to 32.2%) and 12.5% (1.0 to 24.0%), respectively. 12.1% of study subjects had VA worse than 6/18 (20/60).

This study provides baseline information on prevalence of all grades of retinopathy and STDR in consecutive cases attending an urban/semi-urban diabetes clinic in sub-Saharan Africa. Prevalence of STDR was high and in type 2 diabetes was associated with albuminuria, neuropathy and insulin use.

To determine the prevalence of glaucoma within the indigenous Australian population living in central Australia.

1884 individuals aged ≥20 years, living in one of 30 remote communities within the statistical local area of ‘Central Australia,’ were recruited for this study. This equated to 36% of those aged ≥20 years and 67% of those aged ≥40 years within this district. Slit-lamp examination of the anterior segment and intraocular pressure measurement, followed by stereoscopic slit-lamp funduscopy of the optic nerve, was performed. Selected patients underwent automated visual-field testing. The diagnosis of glaucoma was based on pre-existing definitions. Glaucoma prevalence data are presented.

Seventeen individuals had glaucoma (0.90%). Causes of secondary glaucoma were found in four with neovascular glaucoma, two with uveitic glaucoma and four who had developed glaucoma subsequent to trauma or surgery. The remaining seven had no identifiable cause for their glaucoma and were thus classified as open-angle glaucoma equating to a prevalence of 0.52% (95% CI 0.14% to 0.90%) for those aged ≥40 years. Of these, four had an intraocular pressure ≤21 mm Hg, and three had an intraocular pressure >21 mm Hg.

The prevalence of open-angle glaucoma among indigenous Australians within central Australia was 0.52% for those aged ≥40 years. After adjustment for the age distribution of our sample, this is one-third the prevalence seen among the non-indigenous Australian population and is despite a higher prevalence of ocular parameters considered to be associated with glaucoma.

The authors address the question of whether vascular endothelial growth factor inhibitors (anti-VEGF) lead to better clinical outcomes than current treatments in patients with clinically manifest diabetic macular oedema (DMO), which is the leading cause of vision loss in the working age population in developed countries.

The authors performed a systematic literature search in common databases and compiled the evidence according to the GRADE methodology. The authors analysed clinically relevant improvement of visual acuity, vision-related quality of life and local or systemic adverse events.

In a proportion of patients (on average 25%), VEGF inhibitors result in better visual acuity (≥15 ETDRS letters or equivalent) than in patients treated with laser photocoagulation or sham injection. The number of injections required for long-term improvement as well as the general long-term efficacy is unknown. The evidence is not sufficient to confirm safety of the products in patients with DMO and does not suggest superiority of a single product.

For some patients with DMO, VEGF inhibitors seem to be more effective as a short-term treatment option than alternative therapies. The evidence is not of sufficient quality to confirm safety. Decisions on financing should take into account the high price difference between the products and ongoing research.

To compare the outcomes of non-posturing macular-hole surgery using sulfur hexafluoride (SF₆) gas versus perfluoroethane (C₂F₆) for idiopathic macular hole repair.

Interventional, comparative cohort study.

39 eyes of 38 patients undergoing macular-hole surgery with SF₆ were compared with another consecutive group of 39 eyes (39 patients) in whom C₂F₆ was used. All patients were operated on by a single surgeon and underwent 23G transconjunctival phakovitrectomy with no prone posturing in the postoperative period. The best-corrected Snellen's visual acuity (VA) was converted to the logarithm of minimal angle of resolution (logmar) visual acuity for analysis. Optical coherence tomography documentation of anatomical closure and complications of surgery were recorded.

Primary hole closure was achieved in 89.75% in the C₂F₆ group and 87.2% in the SF₆ group. Secondary closure after non-posturing redo surgery with heavy oil (Oxane-HD) was 100% in both groups. The mean preoperative VA in the C₂F₆ group and SF₆ group was 0.81 logMAR and 0.78 respectively. 2 weeks after surgey, SF₆ was completely absorbed in all cases, and the mean VA improved to 0.5 logMAR; however, it remained 1.9 logMAR in the C₂F₆ group. The final mean VA at 6 months was 0.44 (range 0–0.78) and 0.38 (range 0–1) in the C₂F₆ and SF₆ group respectively. There were no instances of pupillary capture in the SF₆ group, whereas there were four in the C₂F₆ group.

Macular-hole surgery with SF₆ gas achieves similar results to C₂F₆ and is absorbed faster, allowing quicker visual rehabilitation for the patient.

Total volume using a standard single inferonasal injection for sub-Tenon's anaesthesia is limited by an increase in intraocular pressure (IOP) and commonly requires the operating surgeon to top-up the block intraoperatively. This study compares the efficacy and safety of a two-quadrant technique that allows the use of a higher volume of local anaesthetic.

54 patients undergoing vitrectomy were randomised into two groups. The control group (n=27) received a standard 5 ml single inferonasal sub-Tenon injection of a 50:50 mixture of 2% lidocaine and 0.5% bupivacaine with 150 IU hyaluronidase. The study group (n=27) received a 5 ml inferonasal and 5 ml superotemporal injection of the same mixture (10 ml total). The primary outcome measure was the number of intraoperative top-ups required. Secondary outcome measures were intraoperative and postoperative pain scores, IOP, block onset time, ocular akinesia, eyelid akinesia and chemosis.

24 patients required a top-up in the control group. No patients required a top-up in the study group (p<0.001). IOP measurements were similar in both groups. Block onset was shorter, eyelid akinesia was improved and pain scores were also reduced in the study group intraoperatively and at 0–2 h, 4–6 h, 10–14 h and 20–24 h postoperatively.

Two-quadrant sub-Tenon's anaesthesia using 10 ml of a 50:50 mixture of 2% lidocaine and 0.5% bupivacaine with 150 IU hyaluronidase seems to be more effective than a single-quadrant technique at reducing intraoperative and postoperative pain during vitrectomy.

To describe a novel technique of sclerotomy construction to facilitate 20-gauge transconjunctical sutureless vitrectomy (TSV) along with the evaluation of the wound integrity.

The surgical technique is described. One hundred consecutive patients who underwent TSV were evaluated for wound leaks, postoperative hypotony, endophthalmitis and any other complication related to surgery. The sclerotomies of eight patients (24 ports) were analysed by imaging with anterior segment optical coherence tomography immediately after surgery, and on the first postoperative day and after the first postoperative month.

104 eyes of 100 patients were evaluated with a mean follow-up of 9.6 months. All cases underwent surgery with standard 20-gauge instrumentation and vitrectomy techniques. Five sclerotomies were found to leak at the end of surgery, requiring a suture. Anterior segment optical coherence tomography images were obtained from eight eyes with good apposition of the tunnel noted in all the cases. Mean intraocular pressure was 18.7 mm Hg on the first postoperative day. One patient had hypotony without leak and this patient had pre-existing hypotony due to chronic panuveitis. There was no instance of postoperative endophthalmitis.

This technique of 20-gauge TSV achieves good wound apposition with a low incidence of complications while using standard 20-gauge instrumentation and vitrectomy techniques.