Association of Choroidal Neovascularization and Central Serous Chorioretinopathy With Optical Coherence Tomography Angiography

Abstract

Importance: Choroidal neovascularization (CNV) is a major cause of vision loss in chronic central serous chorioretinopathy (CSCR). Detecting CNV using fluorescein angiography (FA) may be challenging owing to the coexistence of features related to the primary diagnosis of CSCR. Optical coherence tomography angiography (OCTA) allows noninvasive visualization of retinal and choroidal vasculature via motion contrast and may contribute to the unequivocal diagnosis of CNV in this population.

Objective: To evaluate the sensitivity of spectral-domain OCTA in detecting CNV associated with chronic CSCR.

Design, setting, and participants: Observational cross-sectional study including 23 patients (27 eyes) who presented at the New England Eye Center between August 1, 2014, and November 30, 2014, with suspected CNV complicating chronic CSCR and underwent standard assessment for CNV diagnosis, including FA imaging. Participants were prospectively recruited to receive imaging tests using prototype OCTA software on a commercially available spectral-domain OCT. Orthogonal registration and the merging of 2 consecutive image sets were used to obtain 3 × 3-mm and 6 × 6-mm OCT angiograms centered at the macula. Two independent readers masked to other imaging findings performed a qualitative analysis on OCTA depictions of vascular flow representing CNV and the morphologic appearance of CNV.

Main outcomes and measures: Choroidal neovascularization location as well as retinal pigment epithelial detachment internal reflectivity and the presence of subretinal and intraretinal fluid. Sensitivity and specificity of OCTA in detecting CNV were estimated using FA as the standard examination reference.

Results: Choroidal neovascularization was diagnosed in 8 of 27 eyes (30%) based on FA imaging analysis. Optical coherence tomography angiography and corresponding OCT B-scans detected 100% (8 of 8) of these CNV lesions and correctly excluded 100% (19 of 19) of eyes with CSCR without CNV. Sensitivity was 100% (95% CI, 0.62-1) and specificity was 100% (95% CI, 0.82-1). Morphologic appearance, location, and position of the CNV relative to the retinal pigment epithelium and Bruch membrane were described using OCTA that combined flow and structural information.

Conclusions and relevance: This study suggests that OCT alone (OCTA and coregistered OCT B-scans) features sensitivity and specificity comparable with FA for the detection of CNV in eyes with chronic CSCR.

Figure 1. Choroidal Neovascularization on 3×3-mm Optical Coherence Tomography Angiography in 4 Eyes

B-scans show segmentation boundaries representing inner (green) and outer (red) lines. Artifact removal subtracted the retinal vessel shadowing from the en face flow image and enabled visualization of choroidal neovascularization. A and B, Choroidal neovascularization shows well-circumscribed vessels. C and D, Choroidal neovascularization consists of poorly circumscribed vessels.

Figure 2. Choroidal Neovascularization Appearance After Manual Depth Adjustment of the Outer Boundary on a Coregistered B-Scan

Choroidal neovascularization (blue arrowheads) partially identified on fluorescein angiography (A) and optical coherence tomography angiography (B) using automated depth segmentation. The manual adjustment of segmentation allowed for entire choroidal neovascularization visualization. The feeder vessels (pink arrowheads) are identified on indocyanine green angiography (C) and optical coherence tomography angiography (D).

Figure 3. Feeder Vessel and Choroidal Neovascularization After Manual Adjustment of the Outer Boundary on a Coregistered B-Scan

Fluorescein angiography (A) and an optical coherence tomography angiogram (B) show choroidal neovascularization. Optical coherence tomography angiography with manual adjustment of the outer red segmentation line shows larger choroidal neovascularization and the feeder vessel (arrowhead) originating from the scar area (C). B-scans for panels B (D) and C (E).

Figure 4. Inability in Delineating Margins of Choroidal Neovascularization on Optical Coherence Tomography Angiography

Optical coherence tomography angiography of an eye previously treated with photodynamic therapy for choroidal neovascularization. A and B, Automated segmentation at the outer retinal level shows large and poorly circumscribed choroidal neovascularization. C and D, Manual adjustment of the segmentation lines was unable to accurately identify margins of the choroidal neovascularization.

Figure 5. Eyes Without Evidence of Choroidal Neovascularization on Optical Coherence Tomography Angiography

Absent abnormal vascular flow and the presence of well-circumscribed areas without an optical coherence tomography signal suggest shadowing artifacts in the presence of retinal pigment epithelial detachment. Coregistered B-scans show different retinal pigment epithelial detachment reflectivities. A, Retinal pigment epithelial detachment with homogeneous hyporeflectivity. B–D, Retinal pigment epithelial detachment with heterogenous hyperreflectivity. Asterisks indicate the locations of pigment epithelial detachment on the respective optical coherence tomography angiograms.