Abstract
Purpose: :
To describe changes over time of a new non-invasive en face spectral domain optical coherence tomography (SD-OCT) imaging technique, the Minimum Intensity Projection Software (MinIP) which identifies areas of occult choroidal neovascularization (CNV) without fluorescein angiography and associated areas of fluid.
Methods: :
Fifteen eyes of 15 patients with CNV due to AMD who were followed after anti-VEGF treatment and imaged on SD-OCT (Carl Zeiss Meditec, Inc., Dublin, CA) on at least 2 visits were evaluated retrospectively. At each follow up visit, the en face fundus images generated by the MinIP software were compared qualitatively to the corresponding color, red-free fundus photographs, and fluorescein angiography.Qualitative analysis of development of the white signal provided by the MinIP software, presumably corresponding to occult CNV, and black signal presumably corresponding to intraretinal or subretinal fluid, was performed.
Results: :
MinIP images in eyes with CNV showed a white area similar in shape, often slightly larger, but often more easily defined than the pattern of occult CNV on fluorescein angiography, usually not detected on fundus photographs, and which usually did not change over time following treatment even if fluorescein staining of occult CNV became less apparent over time. In contrast, darkened areas that corresponded to location of intraretinal or subretinal fluid visible on OCT B-scans did decrease substantially over time following anti-VEGF treatment of CNV.
Conclusions: :
Occult CNV detected with MinIp software, usually visualized on fluorescein angiography but not color or red-free fundus photographs, does not appear to change over time following treatment of CNV, while areas of fluid detected by the software do resolve over time following anti-VEGF treatment. MinIP images potentially could be used to identify onset of CNV without fluorescein angiography, and potentially guide identification of growth of CNV or resolution of fluid following anti-VEGF therapy of CNV.
Keywords: age-related macular degeneration • imaging/image analysis: clinical