Background: To determine the prevalence and characteristics of diabetic retinopathy (DR) among Iranian patients with diabetes. Methods: Design: population-based cross-sectional study. Participants: patients with diabetes aged 25 to 64 years in Tehran province, Iran. This survey was conducted from April to October 2007. The study sample was derived from the first national survey of risk factors for non-communicable disease. Diabetes mellitus was defined as a fasting plasma glucose of ≥ 7.0 mmol/l (126 mg/dl) or more, use of diabetic medications, or a physician's diagnosis of diabetes. All patients known to have diabetes underwent an eye examination by bio-microscope and indirect ophthalmoscope to check for any signs of DR through dilated pupils by + 78 lens. Participants were also interviewed and examined to determine their demographic characteristics, medical conditions and the regularity of their eye visits. Results: Among 7989 screened patients, 759 (9.5%) had diabetes. Of them, 639 patients (84.2%) underwent eye examination. Five patients (0.7%) with media opacity were excluded. Of 634 examined patients with diabetes, 240 had some degree of diabetic retinopathy, and the overall standardized prevalence of any retinopathy was 37.0% (95% CI: 33.2-40.8), including 27.3% (95% CI: 23.7-30.8) (n = 175) with non-proliferative and 9.6% (95% CI: 7.3-11.9) (n = 65) with proliferative diabetic retinopathy. Clinically significant macular edema and vision-threatening retinopathy were detected in 5.8% (95% CI: 4.0-7.7) (n = 38) and 14.0% (95% CI: 11.3-16.7) (n = 95) of patients, respectively. Only 143 patients (22.6%) with diabetes had a history of regular eye examination. Conclusion: This study demonstrated a high prevalence and poor control of DR in Tehran province. This suggests the need for adequate prevention and treatment in patients with diabetes.

Purpose: To examine the safety of a single intravitreal injection of autologous bone Marrow Mesenchymal stem cells (MSCs) in patients with advanced retinitis pigmentosa (RP). Methods: A prospective, phase I, nonrandomized, open-label study was conducted on 3 eyes of 3 volunteers with advanced RP. Visual acuity, slit-lamp examination, fundus examination, optical coherence tomography, fundus auto-fluorescence, fluorescein angiography and multifocal electroretinography were performed before and after an intravitreal injection of approximately one-million MSCs. The patients were followed for one year. Further evaluation of MSCs was performed by injection of these cells into the mouse vitreous cavity. Results: No, adverse events were observed in eyes of 2 out of 3 patients after transplantation of MSCs. These patients reported improvements in perception of the light after two weeks, which lasted for 3 months. However, severe fibrous tissue proliferation was observed in the vitreous cavity and retrolental space of the third patient's eye, which led to tractional retinal detachment (TRD), iris neovascularization and formation of mature cataract. Injection of this patient's MSCs into the vitreous cavity of mice also resulted in fibrosis; however, intravitreal injections of the two other patients' cells into the mouse vitreous did not generate any fibrous tissue. Conclusion: Intravitreal injection of autologous bone marrow MSCs into patients' eyes with advanced RP does not meet safety standards. Major side effects of this therapy can include fibrosis and TRD. We propose thorough evaluation of MSCs prior to transplantation by intravitreal injection in the laboratory animals.\