Polyps in Polypoidal Choroidal Vasculopathy Appear as Tangled Vascular Structures Using Swept-Source OCT Angiography

Abstract

Purpose :
To report the morphologic characteristics of polyps and their relationship to branching vascular networks (BVNs) in eyes with PCV using swept source OCT angiography (SS-OCTA).

Methods : Patients with the diagnosis of PCV were recruited from Shanghai General Hospital. All patients underwent a complete ophthalmological examination, including medical records review, best corrected visual acuity (BCVA), fundus photography, simultaneous FA and ICGA, SS-OCT and SS-OCTA .SS-OCTA was performed using a 3×3 mm and 6×6 mm macular raster scan centered on the lesion in all cases. For en face imaging, first a custom segmentation strategy was used to visualize the BVNs and polyps. The inner boundary followed the RPE and the outer boundary followed Bruch’s membrane, also known as the RPE-fit boundary layer on the instrument. The segmentation boundaries were then manually adjusted to optimally visualize the polyps and BVNs.Polyps in eyes with PCV were characterized using multimodal imaging that included fundus photography, fluorescein angiography (FA), indocyanine green angiography (ICGA), swept source OCT imaging (SS-OCT), and SS-OCTA, and the images were anatomically aligned.

Results : Twenty-three eyes of 20 patients were imaged and diagnosed with PCV. ICGA identified 43 polypoidal lesions and all of them correspond to the structures that appeared as clusters of tangled vessels on SS-OCTA images. In addition, SS-OCTA detected 16 additional tangled vascular structures not seen on ICGA. Branching vascular networks (BVNs) were detected on SS-OCTA imaging in all eyes, but ICGA identified BVNs in only 17 of 23 eyes (74%). Of the 43 tangled vascular structures, 40 (93%) were found to be located at the edge of a BVN and 3 (7%) were associated with type 2 neovascularization (NV).

Conclusions : In eyes with PCV imaged by SS-OCTA, previously described polyps were found to appear like tangled vascular structures associated with BVN or type 2 NV. SS-OCTA was superior to ICGA in detection and characterization of the polypoidal lesions in PCV.

This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.

 

Multimodal imaging of a patient with PCV

 

Multimodal imaging of a patient with PCV and type 2 CNV