Noninvasive Investigation of Deep Vascular Pathologies of Exudative Macular Diseases by High-Penetration Optical Coherence Angiography

Abstract

A newly developed high-penetration Doppler optical coherence angiography (HP-OCA) with a 1-μm probe beam for noninvasive investigation of vascular pathology of exudative macular diseases is introduced. A descriptive case series is presented to discuss the clinical utility of HP-OCA. Eleven eyes of 10 subjects with exudative macular disease, including two eyes with myopic choroidal neovascularization (mCNV); four eyes with AMD; and five eyes with polypoidal choroidal vasculopathy (PCV) were investigated. Two Doppler scanning modes (bidirectional and high-sensitive) of HP-OCA were used for the investigation. HP-OCA provides depth-resolved and en face angiograms and a structural OCT noninvasively. The HP-OCA images were compared with fluorescein angiography (FA); indocyanine green angiography (ICGA); and color fundus images. The abnormal vasculature patterns observed with high-sensitive HP-OCA presented high similarity to the midphase of ICGA. Several abnormal Doppler signals were observed in the en face high-sensitive HP-OCA and were colocated with FA leakage. This colocation was found in one eye with mCNV, four eyes with AMD, and one eye with PCV. Doppler tomogram of the bidirectional mode showed abnormal Doppler signals in three of five PCV cases beneath the pigment epithelium detachment. With the high-sensitive mode, Doppler signals were found beneath the elevated retinal pigment epithelium in all untreated cases. HP-OCA revealed depth-resolved abnormal vasculatures in exudative macular diseases. The en face HP-OCA images showed high similarity with FA and ICGA images. These results suggest HP-OCA can be used for noninvasive and three-dimensional angiography in a clinical routine.