Optical coherence tomography (OCT), as a high-resolution, non-invasive, in-vivo image method has been widely used in retinal field, especially in the examination of fundus diseases. Nowadays, the modality has been gradually popularized in most of the national basic-level hospitals. However, OCT is only employed as a diagnostic tool in most cases, ophthalmologists lack of awareness of further exploring the information behind the raw data. In the era of fast-developing artificial intelligence, on the basis of standardized information management, a more comprehensive OCT database should be established. Further original image processing, lesion analysis, and artificial intelligence development of OCT images will help improve the understanding level of vitreoretinal diseases among clinicians and assist ophthalmologists to make more appropriate clinical decisions.
Circular RNA (circRNA) is a new group of endogenous non-coding RNAs produced by back-splicing, which has multiple molecular functions such as acting as microRNA sponges, regulators of transcription and splicing, adaptors for protein-protein interaction. Recent studies have shown that circRNA play an essential role in development and progression of retinal microvascular dysfunction, diabetic retinopathy, age-related macular degeneration, proliferative vitreoretinopathy, eye diseases caused by hyperhomocysteine and ocular malignancy. In pathological conditions, the differential expression of circRNA alters the transcription and translation of corresponding genes, thus changing the activity and function of cells. CircRNA may become a new marker and prognostic indicator of fundus diseases, and its targeted intervention may also become a potential treatment for fundus diseases.
ObjectiveTo observe the flow density (FD) of macular and optic disc and area of foveal avascular zone (FAZ) in severe nonproliferative diabetic retinopathy (S-NPDR).MethodsA prospective cross-sectional study. From October 2019 to April 2020, 31 eyes of 25 S-NPDR patients (S-NPDR group) who were diagnosed in the ophthalmological examination of Jiangsu Province Hospital and 30 eyes of 30 age- and sex-matched healthy volunteers (control group) were included in this study. Optical coherence tomography angiography (OCTA) was used to scan the macular area of 6 mm×6 mm and optic disc of 4.5 mm×4.5 mm. The software automatically divides it into three concentric circles centered on the macular fovea, which were foveal area with a diameter of 1 mm, parafoveal area of 1 to 3 mm, and foveal peripheral area of 3 to 6 mm. The area around the optic disc was divided into 8 areas: nasal upper, nasal lower, inferior nasal, inferior temporal, temporal lower, temporal upper, superior temporal and superior nasal. The FD of the optic disc, the superficial capillary layer (SCP) and deep capillary layer (DCP) of the retina and FAZ area were measured. The FD and FAZ area were compared between the two groups by independent sample t test. The correlation between FAZ area and FD was analyzed by Pearson correlation.ResultsIn parafoveal and perifoveal area, compared with the control group, the FD of SCP (t=6.470, 5.220; P＜0.001) and DCP (t=7.270, 7.370; P＜0.001) decreased in S-NPDR group. In foveal area, there was statistically significant difference in the FD of DCP between the two groups (t=2.250, P=0.030), while the difference in FD of SCP between the two groups was not statistically significant (t=0.000, P=0.900). The FAZ area in S-NPDR group was larger than that in control group, and the difference was statistically significant (t=2.390, P=0.030). The FD in the S-NPDR group was lower than that in the control group except the superior nasal, the difference was statistically significant (t=7.520, 5.000, 4.870, 3.120, 2.360, 2.120, 5.410, 5.560, 2.640; P＜0.05). Pearson correlation analysis showed that the FAZ area of S-NPDR was negatively correlated with FD of SCP (r=－0.513, P=0.004), and had no correlation with FD of DCP (r=0.034, P=0.859).ConclusionThe overall FD in macular area and optic disc of patients with S-NPDR decreased and the FAZ area enlarged.
Replacement of diseased retinal pigment epithelium (RPE) cells with healthy RPE cells by transplantation is one option to treat several retinal degenerative diseases including age-related macular degeneration, which are caused by RPE loss and dysfunction. A cellular scaffold as a carrier for transplanted cells, may hold immense promise for facilitating cell migration and promoting the integration of RPE cells into the host environment. Scaffolds can be prepared from a variety of natural and synthetic materials. Strategies, such as surface modification and structure adjustment, can improve the biomimetic properties of the scaffolds, optimize cell attachment and cellular function following transplantation and lay a foundation of clinical application in the future.