Choriocapillaris Degeneration in Geographic Atrophy
Elliott H Sohn1, Miles J Flamme-Wiese1, S Scott Whitmore1
1Institute for Vision Research, University of Iowa, Iowa City, Iowa; Department of Ophthalmology and Visual Sciences, University of Iowa, Iowa City, Iowa.
The American Journal of Pathology
|May 4, 2019
Summary
Early age-related macular degeneration (AMD) involves significant loss of choriocapillaris, the crucial blood supply for photoreceptors. This microvascular degeneration worsens with geographic atrophy (GA) and impacts dry AMD progression.
Area of Science:
- Ophthalmology
- Vascular Biology
- Retinal Diseases
Background:
- Early age-related macular degeneration (AMD) is linked to choriocapillaris degeneration.
- The role of microvascular changes in AMD progression requires further investigation.
Purpose of the Study:
- To quantify vascular changes in the choriocapillaris and outer choroid during AMD progression.
- To compare vascular degeneration in early AMD and geographic atrophy (GA).
Main Methods:
- Human donor maculae from controls, early AMD, and GA cases were analyzed.
- Ulex europaeus agglutinin-I labeling identified intact and ghost vessels.
- Morphometric analysis assessed choriocapillaris density and outer choroid vascularization.
Main Results:
- Significant choriocapillaris loss was found in early AMD and was more severe in GA.
- Outer choroid vascularization did not differ significantly between controls, AMD, and GA.
- Vascular endothelial growth factor-A levels correlated negatively with choriocapillaris density.
Conclusions:
- Choroidal microvascular degeneration, particularly in the choriocapillaris, is a key feature of dry AMD progression.
- Targeting capillary loss presents a potential therapeutic strategy for AMD.
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