The purpose of this study is to determine if diabetic retinopathy can be treated with prostaglandin analogues, prostaglandin synthesis inhibitors or carbonic anhydrases inhibitors.

Disturbances in retinal perfusion is believed to be involved in the pathophysiology of diabetic retinopathy. These disturbances may be due to changes in the basal diameter of retinal arterioles and to disturbances in the autoregulation of the diameter of these vessels when the blood pressure and the retinal metabolism changes. In vitro studies have shown that prostaglandins and carbonic anhydrases inhibitors are involved in the tone regulation of retinal arterioles, but it is unknown whether this finding is relevant in clinical practice. This can be tested in vivo by an retinal vessel analyzer measuring the dynamics of the retinal vessel diameter changes.

Inclusion Criteria:

• Diabetes type 1 with moderate diabetic retinopathy/healthy
• Blood pressure < 135/85 mmHg

Exclusion Criteria:

• Eye disease (excluding diabetic retinopathy)
• Allergic
• Kidney disease
• Liver disease
• Severe asthma
• Heart disease
• Hypertension arterial
• Users of drugs that influence the metabolism of the prostaglandins in the carbon dioxide
• Pregnant and breastfeeding women and women who don't use secure contraception
• Persons who can't do without contact lens in the treated eye.