Underlying Microstructure of Parapapillary Deep-Layer Capillary Dropout Identified by Optical Coherence Tomography
Eun Ji Lee1, Tae-Woo Kim1, Seung Hyen Lee2
1Department of Ophthalmology, Seoul National University College of Medicine, Seoul National University Bundang Hospital, Seongnam, Korea.
Investigative Ophthalmology & Visual Science
|March 16, 2017
Summary
Microvasculature dropout in primary open-angle glaucoma is linked to specific parapapillary atrophy zones. The underlying microstructure of these areas is not distinct from unaffected regions.
Area of Science:
- Ophthalmology
- Glaucoma Research
- Optical Coherence Tomography Angiography
Background:
- Primary open-angle glaucoma (POAG) is a leading cause of irreversible blindness.
- Parapapillary deep-layer microvasculature dropout (MvD) is a newly identified OCT Angiography (OCTA) finding in POAG.
- Understanding the microstructural basis of MvD is crucial for glaucoma diagnosis and progression assessment.
Purpose of the Study:
- To characterize the microstructural features associated with parapapillary deep-layer microvasculature dropout (MvD) in primary open-angle glaucoma (POAG).
- To investigate the relationship between MvD and different zones of parapapillary atrophy (PPA).
- To compare the peripapillary microstructure in POAG eyes with and without MvD.
Main Methods:
- Swept-source OCTA was used to identify and define parapapillary MvD.
- 188 POAG patients with MvD and 72 age-matched POAG controls without MvD were included.
- Swept-source OCT imaging was performed to assess peripapillary structure and measure juxtapapillary choroidal thickness (JPCT).
Main Results:
- MvD was observed in areas of β-zone, γ-zone, and mixed-zone PPA.
- Eyes with β-zone MvD showed noticeable choroidal thickness without significant thinning.
- Juxtapapillary choroidal thickness was comparable between eyes with MvD and control eyes.
- No distinguishable microstructural features were found in the γ-zone, irrespective of MvD presence.
Conclusions:
- Parapapillary deep-layer MvD in POAG is associated with both β- and γ-zones of PPA.
- The microstructural characteristics of PPAs with MvD are not distinguishable from those without MvD.
- Further research is needed to elucidate the specific mechanisms underlying MvD in POAG.
