ObjectiveTo observe the imaging features of branching vascular network (BVN) in polypoidal choroidal vasculopathy (PCV). MethodsEighty PCV patients (90 eyes) were enrolled in this study. The patients included 58 males and 22 females. The age was ranged from 49 to 85 years, with a mean age of 61.4 years. All the patients were examined for fundus photography, fundus fluorescein angiography (FFA), indocyanine green angiography (ICGA) and optical coherence tomography (OCT). The fibrovascular retinal pigment epithelium detachment (PED) was defined as a well-demarcated subretinal heterogeneous plaque with increasing fluorescence on FFA. The late lichenoid hyperfluorescent plaque was defined as a well-demarcated lichenoid hyperfluorescent plaque on late phase ICGA. The double-layer sign on OCT was defined as a wide range of shallow PED from Bruch membrane. ResultsBVN were found on early ICGA in 76 eyes among the 90 eyes (84.4%). Among these 76 eyes, 18 eyes (23.7%) demonstrated the subretinal reddish-orange branches corresponding to BVN. Fifty-six eyes (73.7%) demonstrated all or part of the BVN on early FFA. Three eyes (3.9%) demonstrated branching transmitted fluorescence corresponding to BVN throughout the FFA. Seventy-three eyes (96.1%) were manifested by occult choroidal vascularization on FFA, and 21 eyes (27.6%) of them were fibrovascular PED. Among the 76 eyes with BVN, all BVN appeared earlier than polypoidal lesions on ICGA. Polypoidal lesions located on the terminal of BVN in 62 eyes (81.6%). Sixty-nine eyes (90.8%) on ICGA demonstrated the late lichenoid hyperfluorescent plaque, whose area was equal to or greater than the area of BVN shown on early ICGA. Seventy-two eyes (94.7%) had the double-layer sign. Among these 72 eyes, 15 eyes (20.8%) had lumen-like structure within the double-layer sign. Sixty-five eyes (90.3%) had punctate and linear hyper-reflectance within the double-layer sign. Two eyes (2.8%) demonstrated a hyporeflective short segment and a gap of Bruch membrane on OCT corresponding to the origin of the BVN. Sixty-three eyes (87.5%) had an area of double-layer sign that matched the area of late lichenoid hyperfluorescent plaque on ICGA. ConclusionsBVN in PCV can be noted as reddish-orange branches on fundus examination. Most of the BVN are shown as early branching transmitted fluorescence but collectively an occult choroidal vascularization on FFA, as lichenoid hyperfluorescent plaque on late ICGA, and as double-layer sign on OCT whose area matches late lichenoid hyperfluorescent plaque.
Macular pigment (MP) is composed of lutein, zeaxanthin, and meso-zeaxanthin, which accumulate mainly at the macula. MP has antioxidant function and can filtering blue wave. Measurement of MP is about its optical density, that is, macular pigment optical density (MPOD). This review summarizes the function and clinical use of MP and MPOD. Researches has show that MPOD is related to some ocular disease such as age-related macular degeneration, macular telangiectasia type 2, diabetic retinopathy, Stargardt disease et al. MPOD can be used in the judgment of clinical diagnosis, treatment effect. The specific mechanism of MP metabolism in the retina and in the pathogenesis of the disease, genotype specific nutritional therapy of xanthophyll, the establishment of a database combined with artificial intelligence and the rapid and convenient MP determination are all issues of great contention that need to be resolved.
Ocular fundus imaging technology has developed rapidly in the past decade. The exsiting imaging technology is constantly updated and new imaging technology emerges one after another. The related research and development investment, equipment usage and paper publication are all growing rapidly. At the same time, it is developing towards the direction of multi-technology combination, integration of artificial intelligence and big data, as well as small-size and automation use of equipment. However, there are many challenges behind the prosperity of ocular fundus imaging, such as professionally remodeling of fundus diseases knowledge system standardization, balance and independence of scholarly communication, misunderstanding of "multimodal images", validation of the effectiveness and applicability of emerging technologies, clinical imaging research innovation, original technology innovation and technology reserve, fundus imaging data integration and analysis system for the future.