Korean J Ophthalmol Vol.23, No.1, 2009 occlusion, vascular permeability, fibrovascular proliferation in retinal neovascularization secondary to proliferative diabetic retinopathy (PDR), and choroidal neovascularization secondary to age-related macular degeneration (AMD).14-17 The purpose of this retrospective study was to evaluate the effect of intravitreal bevacizumab on visual function and retinal thickness in patients with DME. M aterials and M etho ds The present study was designed as a retrospective, con- secutive case series study of eyes with DME treated with off-label intravitreal bevacizumab between March 2007 and February 2008. We reviewed the clinical records of 28 con- secutive patients (30 eyes) with DME treated with at least one intravitreal injection of 1.25 mg of bevacizumab. Because there are no evidence-based indications for the treatment of DME with bevacizumab, we included a wide range of patients with diffuse, clinically significant DME who did not respond to other treatments such as photocoagulation, intravitreal triamcinolone injection, or pars plana vitrectomy. The inclusion criteria for the study eye included (1) best-corrected visual acuity (BCVA) ≤20/40, (2) clinically definite retinal thickening due to DME involving the center of the macula, (3) optical coherence tomography (OCT) central retinal thickness ≥275 µm, and (4) no history of treatment for DME within the prior 3 months. Exclusion criteria included macular edema due to a cause other than diabetes, other ocular condition that might affect macular edema or alter visual acuity, and evidence of external ocular infection. Each patient underwent a complete eye examination, including determination of BCVA, slit-lamp examination, intraocular pressure (IOP) measurement, stereoscopic bio- microscopy of the retina using a 90-diopter lens, and retinal thickness measurement by OCT (Stratus OCT model 3000; Carl Zeiss Meditec Inc., San Leandro, CA), at baseline and at each visit. Patients were examined at 1 week and 1 month after injection, and then at 1- or 2-month intervals at the discretion of the investigator. OCT images were obtained by fast macular thickness map scan (6-radial line pattern), and the central retinal thickness was measured using retinal map analysis for the calculation of average thickness at the center point. Each patient’s BCVA was transferred from his or her records and converted to a logarithm of the minimum angle of resolution (logMAR) scale for analysis. Topical anesthesia was induced by applying proparacaine (0.5%) eye drops before injection. The conjunctiva bulbi and the fornices were repeatedly rinsed with povidone-iodine, which was also applied to the eyelid margins and the lashes to avoid expression of the meibomian glands. After appli- cation of a sterile drape and subconjunctival injection of anesthesia (2% lidocaine containing 1:100,000 epinephrine), a 30-gauge needle on a 1 cm3 syringe was used to inject bevacizumab intravitreally through the pars plana 3.5 to 4.0 mm posterior to the limbus, at a dose of 1.25 mg in 0.05 mL. The needle was carefully removed using a sterile cotton applicator to prevent reflux. After injection, antibiotic eye drops were applied four times per day for 3 days. All patients provided written informed consent, and they were informed of the off-label use of the drug and its potential risks and benefits, as well as the likelihood that additional treatments might be required. The paired t-test was used for comparison of preoperative and postoperative BCVA and central retinal thickness. The multiple regression analysis was performed to evaluate the associated factors influencing treatment success, and Mann-Whitney U test was used to compare response to treatment between nonvitrectomized eyes and previously vitrectomized eyes. For all statistical tests, a p value <0.05 was considered statistically significant. The data were analyzed using statistical software (SPSS, version 12.0, SPSS Inc, Chicago, Illinois, USA). Results Table 1. Baseline characteristics of the study eyes Variables Gender, male:female Age (years) Diabetes type 1:2 duration (years) Hypertension Stage of retinopathy, severe NPDR* : PDR† Preoperative treatment, focal laser treatment panretinal photocoagulation intravitreal injection of triamcinolone pars plana vitrectomy Mean follow-up period (months) Baseline visual acuity (logMAR) Baseline central retinal thickness (µm) * NPDR=noproliferative diabetic retinopathy; † PDR=proliferative diabetic retinopathy. 18 18:12 57.9±13.8 5:25 15.9±7.6 10 12:18 8 15 4 6 5.26±2.39 0.73±0.36 498.96±123.99