OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY IN GEOGRAPHIC ATROPHY

Area of Science:

• Ophthalmology
• Medical Imaging
• Retinal Diseases

Background:

• Dry age-related macular degeneration (AMD) is a leading cause of vision loss.
• Geographic atrophy (GA) is an advanced form of dry AMD.
• Choriocapillaris (CC) changes are implicated in AMD progression.

Purpose of the Study:

• To analyze choriocapillaris (CC) vessel density (VD) around geographic atrophy (GA) in non-neovascular dry age-related macular degeneration.
• To investigate CC VD using optical coherence tomography angiography (OCTA).

Main Methods:

• Compared CC VD surrounding GA margin with control CC outside GA margin in 29 patients.
• Utilized thresholding and binarization for image analysis.
• Compared CC VD in hyperautofluorescent GA areas versus isoautofluorescent areas.

Main Results:

• Significant CC VD impairment was found surrounding GA margin compared to controls (0.317 vs. 0.461, P < 0.001).
• CC VD impairment was greater in patients with foveal involvement.
• Mean VD was significantly lower in hyperautofluorescent areas compared to isoautofluorescent areas (0.242 vs. 0.327, P = 0.001).
• A positive correlation was found between CC VD surrounding GA margin and subfoveal choroidal thickness (r = 0.332, P = 0.019).

Conclusions:

• Optical coherence tomography angiography (OCTA) reveals CC impairment around GA.
• This CC impairment may precede retinal pigment epithelium alterations.
• OCTA is a valuable tool for detecting CC alterations and evaluating therapeutic responses in AMD.