Clinical Ophthalmology (Oct 2020)
Optical Coherence Tomography Angiography Features of Neovascularization in Proliferative Diabetic Retinopathy
Abstract
Sara Vaz-Pereira,1,2,* João Jesus Silva,2,* K Bailey Freund,3– 5 Michael Engelbert3– 5 1Department of Ophthalmology, Centro Hospitalar Universitário de Lisboa Norte, EPE - Hospital de Santa Maria, Lisbon, Portugal; 2Department of Ophthalmology, Faculdade de Medicina, Universidade de Lisboa, Lisbon, Portugal; 3Vitreous Retina Macula Consultants of New York, New York, NY, USA; 4LuEsther T. Mertz Retinal Research Center, Manhattan Eye, Ear and Throat Hospital, New York, NY, USA; 5Department of Ophthalmology, New York University School of Medicine, New York, NY, USA*These authors contributed equally to this workCorrespondence: Sara Vaz-PereiraDepartment of Ophthalmology, Centro Hospitalar Universitário de Lisboa Norte, EPE - Hospital de Santa Maria, Avenida Professor Egas Moniz, Lisbon 1649-035, PortugalTel +351 217805252Fax +351 217805653Email [email protected]: To describe features of neovascularization in proliferative diabetic retinopathy (PDR) using optical coherence tomography angiography (OCTA).Methods: A retrospective case series was performed in 23 eyes from 21 patients who underwent OCTA of neovascular complexes (NVCs) due to PDR. Eyes were imaged with the DRI Triton swept-source OCTA, Avanti RTVue XR or Cirrus HD-OCT 5000 as part of routine clinical examination. Segmentation was adjusted to include vasculature between the vitreous cavity and the internal limiting membrane (ILM). The presence of NVCs was confirmed by clinical examination and multimodal imaging such as color or red-free fundus photography, fluorescein angiography, multicolor imaging or near-infrared reflectance.Results: Thirty-five NVCs were imaged, of which, 34% were neovascularization of the disc (NVD) and 66% were neovascularization elsewhere (NVE). On structural OCT B-scans, NVE appeared as medium to highly reflective tissue that breached the ILM, while NVD showed highly reflective tissue protruding from the disc in a sea fan configuration. Flow signal was seen on OCTA in all cases of NVE and in 67% of NVD lesions. Areas with minimal or absent retinal flow signal identified retinal nonperfusion areas and were found adjacent to 87% of NVE. Intraretinal microvascular abnormalities (IRMAs) were noted next to 70% of NVE. Absent flow signal was seen in 4 NVD cases showing posterior shadowing and were considered inactive.Conclusion: OCTA appears useful for imaging NVCs, IRMAs, and retinal nonperfusion areas in eyes with diabetic retinopathy. This imaging modality enables noninvasive screening and monitoring of PDR and can obviate the need for additional testing in certain clinical settings.Keywords: diabetes mellitus, diagnostic imaging, proliferative diabetic retinopathy, retinal neovascularization, optical coherence tomography angiography
