In this prospective, open-label clinical study is to investigate the behavior of the retinal functions during development of diabetic macular disease (DME) under the influence of Lucentis. Measurements with the multifocal electroretinogram (ERG) and microperimetry is used here as an objective criteria to information about the retinal function obtain.

Inclusion Criteria:

1. diabetic macular edema with center involvement in at least one eye
2. patients with a central retinal thickness
3. patients with a BCVA of 78-24 EDTRS letters
4. decrease in vision is due to DME and not due to other causes, in the opinion of the investigator
5. Type 1 or type 2 diabetes mellitus diagnosed 2 years prior to screening

Exclusion Criteria:

1. history or evidence of severe cardiac disease
2. clinical or medical history uncontrolled hypertension or diabetes
3. of unstable angina, acute coronary syndrome, myocardial infarction or revascularization with 6 months
4. ventricular tachyarrhythmias requiring ongoing treatment
5. history or evidence clinically significant peripheral vascular disease, such a intermittent claudication or prior amputation
6. clinically significant impaired renal or hepatic function