The purpose of this study is to investigate if a new drug called ranibizumab is effective to treat a rare bilateral disease of the macula: type 2 idiopathic macular telangiectasia (type 2 IMT). 10 patients will receive monthly injections of the drug into one eye over a period of one year.

Type 2 idiopathic macular telangiectasia (type 2 IMT) is a retinal disease of unknown etiology that commonly presents with a slow decrease in visual acuity, reading difficulties and metamorphopsia in the fifth to seventh decade. Diagnosis is based on fluorescein angiography which typically reveals parafoveal leakage in the late phase and may show telangiectatic capillaries in the early phase. In a subset of patients, a proliferative stage with secondary neovascularizations may develop late in the disease course. In the past, there has been no effective treatment for the disease stages without neovascularization.

Recent studies in a limited number of patients with nonproliferative disease have shown promising results after intravitreal injection of bevacizumab, an antagonist targeting vascular endothelial growth factor (VEGF). Bevacizumab resulted in a decrease of parafoveal leakage in fluorescein angiography and a decrease in retinal thickness. An increase in visual acuity was reported in a subset of patients.

The RAMA-Trial is initiated in order to investigate the effect of a ranibizumab. The safety and tolerability of this VEGF-antagonist has been extensively studied in large cohorts of patients suffering from age-related macular degeneration.

Patients with type 2 IMT will receive monthly injections over a period of one year. The above mentioned outcome measures will be assessed.

Inclusion Criteria:

• diagnosis of type 2 idiopathic macular telangiectasia
• minimum of 18 years
• patient must be able to follow protocol
• written informed consent
• best corrected visual acuity between 20/200 - 20/32 in the treated eye

Exclusion Criteria:

• patients who do not fulfill the inclusion criteria
• patients with other retinal vascular disease such as diabetic retinopathy or venous occlusive diseases
• ocular surgery 3 months before study enrollment
• history of uncontrolled glaucoma
• active intraocular inflammation or inflammation of the ocular adnexa
• subfoveal fibrosis in the study eye
• inability to follow study protocol
• major surgery one month before study enrollment
• history of severe cardiovascular disease or history of stroke 6 months before study enrollment
• allergies against substances or components of the study medication
• low anticipated compliance
• patients who participate(d) in clinical trials simultaneously or within the last 60 days
• pregnancy, lactation, women that may become pregnant and don't use safe contraception
• chronic alcohol- or drug abuse within the last year
• lacking legal competence or language ability
• neurologic diseases such as multiple sclerosis
• need of concomitant medication that is not allowed in combination with ranibizumab
• previous intravitreal therapy with anti-angiogenic substances in the study eye within the last 6 months