The Effect of a Single Intravitreal Anti-VEGF Therapy on Optic Nerve Head Perfusion

Study Overview
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Brief Summary
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Age related macula degeneration is one of the most common sight threatening diseases of the elderly. The so called wet form of AMD is caused by choroidal neovascularisation (CNV) of pathological vessels, which lead to leakage, bleeding and macular edema. Several lines of evidence suggest that vascular endothelial growth factor (VEGF) plays a key role in the induction CNV. Recent evidence indicates that overexpression of VEGF in the retinal pigment epithelium may lead to the development of CNV in experimental models, and intravitreal injection of a VEGF blocker prevents the development of experimental CNV. This hypothesis is also supported by the promising effects of anti-VEGF treatment in patients with choroidal neovascularisation. The substances currently in clinical use include ranibizumab (Lucentis®), bevacizumab (Avastin®) and pegaptanib (Macugen®). However, from a physiological point of view, VEGF also serves as a survival factor for existing vessels and for neuronal cells. Moreover, it has been reported that VEGF induces vasodilatation, most probably by an increased production of nitric oxide. Accordingly one may hypothesize that anti-VEGF treatment is associated with ocular vasoconstriction with unknown long term results. Thus, in the current study, the investigators set out to investigate whether the ocular perfusion is affected by a single intravitreal anti-VEGF.

Official Title
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The Effect of a Single Intravitreal Anti-VEGF Therapy on Optic Nerve Head Perfusion

Conditions
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Macular Degeneration, Regional Blood Flow, Vascular Endothelial Growth Factor

Intervention / Treatment
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* Drug: ranibizumab, bevacizumab or pegaptanib


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: 40 subjects ≥ 50 years of age Subjects with all angiographic subtypes of neovascular wet AMD, already scheduled for intravitreal anti-VEGF therapy in one eye Good central or eccentric fixation Exclusion Criteria: History or previous Anti-VEGF therapy History or previous intravitreal injection with any drug Intraocular pressure ≥ 25 Glaucoma History or presence of thromboembolic events Diabetes mellitus Blood donation during the previous 3 weeks Ametropy ≥ 6 dpt

Ages Eligible for Study
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Minimum Age: 50 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Basic Science
Allocation: Non-Randomized
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: 1<br>patients with age-related macular degeneration, which are already scheduled for intravitreal anti-VEGF therapy in one eye are measured before and after treatment. | Drug: ranibizumab, bevacizumab or pegaptanib<br>* measurements are performed one week before and after anti-VEGF intravitreal injection<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Optic nerve head blood flow |  | before, one week after and three weeks after intravitreal injection with an anti-VEGF drug | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Choroidal blood flow |  | before, one week after and three weeks after intravitreal injection with an anti-VEGF drug | 
| Retrobulbar blood flow |  | before, one week after and three weeks after intravitreal injection with an anti-VEGF drug | 
| Intraocular pressure |  | before, one week after and three weeks after intravitreal injection with an anti-VEGF drug | 
| Systemic blood pressure |  | before, one week after and three weeks after intravitreal injection with an anti-VEGF drug | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Age-related macular degeneration, anti-VEGF