접수번호:08-056 Korean Journal of Ophthalmology 2009;23:17-22 ISSN : 1011-8942 DOI : 10.3341/kjo.2009.23.1.17 Intravitreal Bevacizumab for Treatment of Diabetic Macular Edema Jeong Won Seo, MD, In Won Park, MD Department of Ophthalmology, Hallym University College of Medicine, Hallym University Sacred Heart Hospital, Anyang, Korea Purpose: To evaluate the effect of intravitreal bevacizumab on visual function and retinal thickness in patients with diabetic macular edema (DME). Methods: Thirty eyes of twenty-eight patients (mean age, 57.9±13.8 years) with DME were included in this study. Complete ophthalmic examination, including determination of best-corrected visual acuity (BCVA), stereoscopic biomicroscopy, and retinal thickness measurement by optical coherence tomography (OCT), was done at baseline and at each follow-up visit. All patients were treated with a 0.05 mL intravitreal injection containing 1.25 mg of bevacizumab. Results: All patients completed 3 months of follow-up with a mean follow-up period of 5.26±2.39 months. The mean BCVA at baseline was 0.73±0.36 logMAR, which significantly improved to 0.63±0.41 (p=0.02), 0.58±0.36 (p=0.003), and 0.61±0.40 logMAR (p=0.006) at 1 week, 1 month, and 3 months. Final BCVA analysis de- monstrated that 15 eyes (50%) remained stable and 12 (40%) improved ≥2 lines on BCVA. The mean central retinal thickness was 498.96±123.99 µm at baseline and decreased to 359.06±105.97 (p<0.001), 334.40±121.76 (p<0.001), 421.40±192.76 µm (p=0.035) at 1 week, 1 month, and 3 months. No ocular toxicity or adverse effects were observed. Conclusions: Intravitreal bevacizumab injection resulted in significant improvement in BCVA and central retinal thickness as early as 1 week after injection in patients with DME, and this beneficial effect persisted for up to 3 months. However, the slight reduction in this improvement at 3 months suggests that repeated bevacizumab injections might be necessary. To evaluate the long-term safety and efficacy, further prospective randomized controlled clinical trials will be needed. Korean J Ophthalmol 2009;23:17-22 ⓒ 2009 by the Korean Ophthalmological Society. Key Words: Diabetic macular edema, Intravitreal bevacizumab injection Diabetic macular edema (DME) is the leading cause of visual loss in patients with diabetes mellitus, and it frequently leads to irreversible changes in visual acuity.1 DME is caused by excessive vascular permeability, which leads to leakage of fluid and plasma constituents, such as lipoproteins, into the retina. This then causes retinal thickening. The Early Treatment Diabetic Retinopathy Study (ETDRS) showed that focal laser photocoagulation is beneficial in the treatment of clinically significant macular edema, reducing the rate of moderate visual loss by 50%.2 However, only 3% of patients improved by ≥3 lines of vision by the end of the study. Intravitreal triamcinolone acetonide (IVTA) injection has proven effective in improving vision and reducing macular thickness in DME, Received: June 5, 2008 Accepted: November 18, 2008 Reprint requests to In Won Park, MD. Department of Ophthalmology, Hallym University Sacred Heart Hospital, #896 Pyeongchon-dong, Dongan- gu, Anyang-si, Gyeonggi-do 431-070, Korea. Tel: 82-31-380-3835, Fax: 82- 31-380-3837, E-mail: piw@korea.com * The author has no proprietary interest in any of the materials or equip- ment mentioned in this study. both as an initial treatment and as a second line therapy after unsuccessful laser therapy.3,4 However, its effect is temporary, and a number of side effects have been reported.5,6 Conse- quently, its therapeutic value remains unclear. Vascular endothelial growth factor (VEGF) has been imp- licated as an important factor in the breakdown of the blood- retina barrier, with increased vascular permeability resulting in retinal edema in diabetic patients through affecting endo- thelial tight junction proteins.7 While the normal human retina contains VEGF, hypoxia stimulates the secretion of VEGF from retinal pigment epithelial cells.8,9 VEGF levels are significantly elevated in eyes with DME.10,11 In addition, VEGF concentrations are significantly higher in eyes with extensive macular leakage when compared to eyes with minimal leakage.11 Therefore anti-VEGF treatments have been proposed as an alternative adjunctive treatment for DME.12 Bevacizumab (Avastin, Genentech Inc., San Francisco, CA) is a complete full-length humanized antibody that binds to all subtypes of VEGF; it has been used successfully as a systemic drug in tumor therapy.13 Recent studies have demonstrated the usefulness of intravitreal injections of bevacizumab in the reduction of macular edema secondary to central retinal vein 17