ObjectiveTo observe alterations of macular outer retinal reflectivity (ORR) and the associations with macular vessel density in patients with nonproliferative diabetic retinopathy (NPDR). Methods A retrospective cross-sectional study. From August 2021 to March 2022, a total of 63 NPDR patients with 63 eyes (NPDR group) diagnosed by Department of Ophthalmology of Guangdong Provincial People's Hospital were included in the study. There were 39 males with 39 eyes and 24 females with 24 eyes. Age was 60 (52, 68) years. A total of 66 eyes of 66 healthy volunteers matching age and sex were selected as the control group. Among them, 40 men had 40 eyes and 26 women had 26 eyes. Age was 58 (52, 67) years. Optical coherence tomography (OCT) and OCT angiography (OCTA) were performed in all affected eyes. Image J software was used to calculate ORR, including the optical density of ellipsoid zone (EZ), photoreceptor outer segment (OS), photoreceptor inner segment (IS) and outer nuclear layer (ONL) by OCT examination. The sampling sites were horizontal and vertical scanning of the fovea of the macula on 500 μm (nasal500, temporal500, superior500, inferior500), 1 000 μm (nasal1 000, temporal1 000, superior1 000, inferior1 000) and 2 000 μm (nasal2 000, temporal2 000, superior2 000, inferior2 000). The software automatically divided the retina within 6 mm of the macular fovea into the fovea with a diameter of 1 mm, the parafovea with a diameter of 1-3 mm, and the perifovea with a diameter of 3-6 mm by macular OCTA examination. The blood density of superficial capillary plexus and deep capillary plexus in different zones in the macular area were measured by the built-in software of the device. Spearman correlation analysis was used to analyze the correlation between ORR and blood flow density. ResultsCompared with the control group, retinal reflectivity of EZ in NPDR group was significantly decreased at other sites except the fovea, retinal reflectivity of OS was significantly decreased at nasal2 000, temporal2 000, superior2 000 and superior1 000; retinal reflectivity of IS was significantly decreased at superior1 000, superior500 and inferior500. The retinal reflectivity of ONL in macular fovea was significantly decreased, and the differences were statistically significant (P＜0.05). The ORR was positively correlated with blood flow density, and the correlation coefficient in NPDR group was lower than that in control group. The results of multifactor linear regression analysis showed that the superior and temporal ORR were correlated with blood flow density (P＜0.05). ConclusionsCompared with the control group, ORR is reduced and less correlated with vessel density in NPDR patients. ORR is more affected by retinal blood flow density in temporal and superior parts.
Objective To explore the short-term efficacy and safety of intra-arterial thrombolysis (IAT) in the treatment of retinal artery occlusion (RAO) with the assistance of the rescue green channel in the eye stroke center. Methods A prospective, interventional, single-center study. Thirty-eight eyes from 38 RAO patients who received IAT treatment in Guangdong Provincial People’s Hospital were enrolled. All the patients were rescued via the green channel in our eye stroke center. Data from comprehensive ocular examinations including best-corrected visual acuity (BCVA) and optical coherence tomography angiography (OCTA) were collected. BCVA was measured with Snellen chart and converted to the logarithmic minimum angle of resolution (logMAR) unit for statistical analysis. RTVue XR OCTA was used to measure vascular densities (VD) of the superficial capillary plexus (SCP), deep capillary plexus (DCP) and radial peripapillary capillary (RPC), and central retinal thickness (CRT). All RAO eyes attempted IAT treatment and 34 eyes were successful. Four eyes failed to complete IAT because of the occlusion of internal or common carotid arteries on the same side with the RAO eyes. Ocular examinations in post-operative 1-3 days were performed with the same devices and methods as those before surgery. Parameters measured before and after surgery include BCVA, VD of SCP, DCP, RPC, and CRT. Data of the green channel collected include the time intervals from onset of RAO to first presentation in local hospitals, and from onset of RAO to our eye stroke center. Comparisons of VD and CRT between the RAO eyes and contralateral healthy eyes were performed with independent samples Mann-Whitney U test; comparisons of VD and CRT in RAO eyes before and after IAT surgery were performed with paired samples Wilcoxon Rank Sum test. Results Among the 34 RAO patients who had successful IAT surgery, 18 (52.9%, 18/34) were males and 16 (47.1%, 16/34) were females; the mean age was (51.0±12.9) years old. There were 30 and 4 eyes diagnosed as central RAO and branch RAO respectively. The logMAR BCVA before and after IAT surgery was 2.52±0.61 and 2.18±0.85 respectively, and the difference was statistically significant (Z=－3.453, P=0.002). Before surgery, VD of SCP, DCP and RPC were significantly decreased and CRT was significantly increased in the affected eye compared with the contralateral healthy eyes, with the statistical significance (P＜0.001). Compared with those before surgery, the VD of SCP and DCP were significantly improved after surgery (Z=－2.523, －2.427; P=0.010, 0.014), while there was no difference in VD of RPC and CRT (Z=－1.448, －1.454; P=0.150, 0.159). The time interval between onset of RAO and first visit to the hospital was (6.56±6.73) hours; the time interval between onset of RAO and the arrival at our hospital was (24.11±19.90) hours. No cerebral stroke was observed in the early post-operative period and no cerebrocardiovascular events were observed later. he time interval between onset of RAO and the arrival at our hospital was (24.11±19.90) hours. No cerebral stroke was observed in the early post-operative period and no cerebrocardiovascular events were observed later. Conclusions The short-term efficacy and safety of IAT in the treatment of RAO were satisfactory. The rescue time window might be prolonged.