This study investigates the hypothesis that ranibizumab injection given into the eye is an efficacious and safe treatment option applied for swelling of the macula (site of sharp vision) in diabetes.

This is a randomized, controlled, three-center trial to assess the efficacy and safety of intravitreal ranibizumab injections in diabetic macular edema. Comparator arm consists of patients receiving macular grid-pattern laser therapy.

Inclusion Criteria:

• Male or female type I or II diabetic patients over 18 years of age
• Diagnosis of DME secondary to diabetic retinopathy and decrease in vision is due to DME and not due to other causes in the opinion of the investigator
• Patients who have a BCVA score between 78 and 39 letters in the study eye using ETDRS-like visual acuity charts at a testing distance of 4 meters
• Expectation by the investigator that patient will potentially benefit from laser treatment or ranibizumab treatment
• Willing and able to comply with all study procedures

Exclusion Criteria:

• Active intraocular inflammation, any active infection or history of uveitis
• Uncontrolled glaucoma or neovascularization of the iris in the study eye
• Structural damage within 0.5 disc diameter of the center of the macula in the study eye likely to preclude improvement in visual acuity following the resolution of macular edema, including atrophy of the retinal pigment epithelium, subretinal fibrosis, laser scar(s), epiretinal membrane involving fovea or organized hard exudate plaques
• Concurrent disease in the study eye that could compromise visual acuity or prevent the improvement of visual acuity (including diabetic proliferative retinopathy) or require medical or surgical intervention during the study period, including cataract, retinal vascular occlusion, retinal detachment, macular hole or choroidal neovascularization of any cause
• Panretinal laser photocoagulation in the study eye within 6 months prior to or during the study or focal/grid laser photocoagulation in the study eye within 3 months prior to study entry
• Treatment with anti-angiogenic drugs (pegaptanib sodium, anecortave acetate, bevacizumab, ranibizumab, etc) or intravitreal corticosteroids in the study eye within 3 months prior to randomization
• Any intraocular surgery in the study eye within 3 months prior to randomization
• History of vitrectomy in the study eye
• Ocular conditions in the study eye that require chronic concomitant therapy with topical ocular or systemically administered corticosteroids
• Pregnancy and lactation

Diabetes patients having clinically significant macular edema due to diabetic retinopathy.