![]() Several authors have clearly shown neovascularization in PDR using en face OCT angiography. ![]() This was shown in a study by Kuehlewein et al., 18 who described two distinct morphologic patterns of type 1 choroidal neovascularization (CNV): new vessels radiated in a branching pattern either in all directions from the center of the lesion (medusa pattern) or from one side of the lesion (sea fan pattern). 11 – 25 Without the effect of fluorescein leakage, en face OCT angiography can clearly visualize the microvascular structures of neovascularization. Recently developed OCT angiography techniques are gaining popularity for use in three-dimensional noninvasive chorioretinal vascular imaging. However, FA is an invasive and time-consuming examination, and, therefore, it is not frequently performed. 2 – 4 But in actual clinical practice, FA is a useful modality not only to detect neovascularization, but also to ascertain the activity of the neovascularization. In the landmark clinical trials of the Diabetic Retinopathy Study and Early Treatment Diabetic Retinopathy Study (ETDRS), fluorescein angiography (FA) was used as an adjunct for classifying disease severity, evaluating the degree of macular edema, and guiding laser therapy. 1 However, the contrast between the new vessels and background fundus structures, such as intraretinal microvascular abnormality (IRMA) or laser scars, is occasionally fuzzy when closely monitoring the morphologic changes in neovascularization at the microcirculation level. It is observed on fundus biomicroscopy as small and/or large new vessels creating irregular vascular networks either on the retinal surface or protruding into the vitreous cavity. Neovascularization is often associated with tractional retinal detachment and vitreous hemorrhage, which are leading causes of visual loss in patients with diabetes. The hallmark of proliferative diabetic retinopathy (PDR) is neovascularization that occurs at the vitreoretinal interface. The vessel areas of NVD/NVE significantly decreased following PRP ( n = 12, P = 0.019), and NVD/NVE morphology showed pruning and decreased EVP.Įxuberant vascular proliferation on OCT angiograms should be considered as an active sign of neovascularization therefore, morphologic evaluation of neovascularization using OCT angiography may be useful to estimate the activity of each neovascularization in eyes with PDR. The remaining seven treated eyes had pruned NVD/NVE without EVP, observed as fibrotic changes or faint (inactive) leakage in FA. Ninety-five percent of treatment-naïve NVD/NVE observed by OCT angiography had exuberant vascular proliferation (EVP), identified as irregular proliferation of fine (smaller-caliber) new vessels whereas, the presence of EVP in previously treated eyes (13/20) was significantly less than in treatment-naïve eyes (65% vs. All treatment-naïve NVD/NVE had remarkable (i.e., active) leakage in early-phase FA. Twenty eyes had treatment-naïve PDR, whereas 20 eyes were previously treated with PRP. In 12 eyes that were treated or treatment-naïve, changes in the morphology and vessel area of NVD/NVE before and after panretinal photocoagulation (PRP) were investigated. The morphology of NVD/NVE on OCT angiograms was evaluated, and the activity was determined by biomicroscopy and fluorescein angiography (FA). To characterize the morphology of neovascularization at the disc (NVD) and neovascularization elsewhere (NVE) in treatment-naïve or previously treated proliferative diabetic retinopathy (PDR) patients using optical coherence tomography (OCT) angiography.Įn face OCT angiograms of NVD/NVE in 40 eyes of 33 patients with PDR were acquired using RTVue XR Avanti OCT.
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