Rotational Three-dimensional OCTA: a Notable New Imaging Tool to Characterize Type 3 Macular Neovascularization

Area of Science:

• Ophthalmology
• Medical Imaging
• Retinal Diseases

Background:

• Type 3 macular neovascularization (MNV) is a subtype of age-related macular degeneration (AMD).
• Accurate detection and characterization of type 3 MNV are crucial for understanding its pathogenesis and guiding treatment.
• Current 2D imaging techniques may underestimate the prevalence and complexity of type 3 MNV.

Purpose of the Study:

• To investigate the utility of rotational 3D optical coherence tomography angiography (OCTA) for visualizing type 3 MNV.
• To compare the lesion detection rate of 3D OCTA with conventional 2D OCTA.
• To gain novel insights into the spatial characteristics of type 3 MNV using 3D reconstruction.

Main Methods:

• Retrospective analysis of OCTA volume data from 15 eyes with treatment-naïve type 3 MNV and AMD.
• Utilized a prototype algorithm for volume projection removal and volumetric visualization techniques.
• Compared lesion detection and morphology between rotational 3D OCTA and 2D OCTA images.

Main Results:

• Rotational 3D OCTA identified 35 neovascular lesions, significantly more than the 22 lesions detected by 2D OCTA.
• Detected lesions originated from the deep vascular complex and extended through retinal layers to the RPE/sub-RPE space.
• Lesions exhibited varied shapes (saccular and filiform) and were inclined in 3D space, not perpendicular to the RPE/Bruch's membrane.

Conclusions:

• Rotational 3D OCTA, aided by a specialized algorithm, effectively visualizes type 3 MNV.
• This advanced imaging approach increases the detection rate of type 3 MNV lesions.
• 3D OCTA offers valuable new perspectives on the structural characteristics and spatial orientation of type 3 MNV.