Association Between Laser Interferometric Measurement of Fundus Pulsation and Pneumotonometric Measurement of Pulsatile Ocular Blood Flow in Patients With Age-related Macular Degeneration

Study Overview
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Brief Summary
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Several methods have been proposed for the measurement of pulsatile ocular blood flow (POBF). The pneumatic tonometer, which is commercially available, assesses POBF by measurement of intraocular pressure (IOP) changes during the cardiac cycle. The investigators have recently developed a method for the measurement of ocular fundus pulsation, which is based on laser interferometry. In contrast to the Langham system the method is non-contractile and yields a high topographic resolution. Moreover, the pneumatic tonometer assesses the ocular pressure pulse, whereas ocular fundus pulsation is a point measure of the ocular volume pulse. These two parameters are related by the ocular rigidity, which refers to the mechanical properties of the eye coats. Age-related macular degeneration (AMD) is the most common cause of blindness in the industrialized nations. The mechanisms behind this severe eye disease are, however, still obscure. It has been hypothesized that alterations in choroidal blood flow and ocular rigidity may contribute to the development and progression of AMD. However, there is currently little data to confirm this hypothesis. The present study is an attempt to investigate choroidal blood flow and ocular rigidity by employing laser interferometric measurement of fundus pulsation and pneumotonometric measurement of fundus pulsation.

Official Title
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Association Between Laser Interferometric Measurement of Fundus Pulsation and Pneumotonometric Measurement of Pulsatile Ocular Blood Flow in Patients With Age-related Macular Degeneration

Conditions
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Age-related Macular Degeneration

Intervention / Treatment
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* Procedure: blood flow measurement


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients with AMD (defined as soft drusen > 63 µm, hyperpigmentation and/or hypopigmentation of the retinal pigment epithelium (RPE), RPE and associated neurosensory detachment, (peri)retinal hemorrhages, geographic atrophy of the RPE, or (peri)retinal fibrous scarring) Age between 50 and 90 years Exclusion Criteria: Evidence of any other retinal or choroidal vascular disease Regular use of pentoxifylline in the last month before the trial period Evidence of a choroidal neovascular membrane Diabetes mellitus

Ages Eligible for Study
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Minimum Age: 50 Years
Maximum Age: 90 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

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>AMD Patients | Procedure: blood flow measurement<br>* Fundus pulsation amplitude measurement Pulsatile ocular blood flow measurement<br>|
| Active Comparator: 2<br>healthy controls | Procedure: blood flow measurement<br>* Fundus pulsation amplitude measurement Pulsatile ocular blood flow measurement<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Fundus pulsation amplitude |  | 10 minutes measurement of FPA | 
| Pulsatile ocular blood flow |  | 10 minutes measurement of pulsatile ocular blood flow | 
| Ocular rigidity |  | 10 minutes measurement of ocular rigidity | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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AMD, rigidity, pulsatile ocular blood flow, Physiology of the eye