A Comparison of Optical Coherence Tomography Angiography to Fluorescein Angiography for the Imaging of Type 1 Neovascularization

Abstract

Purpose : Optical coherence tomography angiography (OCTA) is a new technique that detects vascular structures using motion or flow characteristics, however, the utility of OCTA for managing neovascularization (NV) in a clinic-based setting is currently unclear. We performed a multicenter, retrospective cohort study to determine the sensitivity of OCTA and fluorescein angiography (FA) for detecting Type 1 NV compared with detection using FA and structural OCT as the gold standard.

Methods : A retrospective review of FA, OCT and OCTA (Optovue RTVue XR Avanti SD-OCT device) imaging performed on a consecutive series of 115 eyes of 100 patients with type 1 NV from 5 institutions. Unmasked graders utilized FA and OCT data to determine the diagnosis of Type 1 NV. Masked graders evaluated FA data alone, en face OCTA data alone, and combined en face OCTA with OCT line scans to determine the presence of Type 1 NV. Sensitivity analyses were performed using FA and OCT information as the reference.

Results : Ten eyes were excluded from analysis because they had type 2 or type 3 NV. Type 1 NV was due to age-related macular degeneration (59 eyes), central serous chorioretinopathy (22 eyes), pachychoroid neovasculopathy (2 eyes) and polypoidal choroidal vasculopathy (22 eyes). One-hundred-and-five eyes (53.3% treatment-naïve) were diagnosed with Type 1 NV using the gold standard. Of these, 90 (85.7%) could be detected using en face OCTA and OCT line scans. The sensitivity of FA data alone and en face OCTA data alone for visualizing Type 1 NV was the same (both 66.7%). Significant factors that precluded visualization of NV using en face OCTA included height of pigment epithelial detachment, low signal strength and a treatment-naïve status (P < 0.05, respectively). Type 1 NV visualized with en face OCTA correlated to sites of leakage/staining on FA in 80.3% of cases. In the remaining 15 eyes (19.7%), en face OCTA identified type 1 NV at sites where fluorescein leakage/staining was not observed.

Conclusions : En face OCTA and OCT line scans showed higher sensitivity to detect Type 1 NV than either FA alone and en face OCTA alone. Although it should not be considered a suitable replacement for combined FA with OCT data (gold standard), en face OCTA and adjunctive OCT line scans may be helpful to diagnose type 1 NV noninvasively.

This is an abstract that was submitted for the 2016 ARVO Annual Meeting, held in Seattle, Wash., May 1-5, 2016.