Objective To observe the expression of vascular endothelial growth factor A (VEGFA) and its receptors sFlt-1, kinase insert domain receptor (KDR) in lightinjured human retinal pigment epithelial (RPE) cells. Methods Cultured human RPE cells (8th - 12th generations) were divided into normal control group and light damage group. The cells of two groups were exposed to the 18 W cold white light (2200±300) Lux for 12 hours to induce light damage responses, but the cells of normal control group were packed by tinfoil with doubledeck high pressure disinfection. The VEGF-A, sFlt-1 and KDR mRNA and protein expressions were detected by reverse transcriptionpolymerase chain reaction (RT-PCR) and Western blot at 0, 6, 12, 24 hours after light damage. Results The VEGF-A mRNA and protein expressions in light damage group were significantly increased at 6 hours, and reached its peak at 12 hours after light damage which obviously higher than that in normal group (t=2.74, 2.93; P＜0.05), and then went down gradually. The sFlt-1 mRNA and protein expressions in light damage group reached its peak at 12 hours after light damage which obviously higher than that in normal group (t=4.32, P＜0.01), but obviously lower than that in normal group at 24 hours after light damage (t=2.41, P＜0.05). The KDR mRNA and protein expressions in light damage group were obviously higher than that in normal group at 24 hours after light damage （t=2.89, P＜0.05）,but there was no changes at 6, 12 hours after light damage (t=1.84, P＞0.05). Conclusions At 6, 12 hours after light damage, the expressions of VEGF-A and sFlt-1 increases significantly and KDR expression is stable in lightinjured RPE cells. At 24 hours after light damage, the expression of VEGF-A and sFlt-1 decreases, but KDR expression increases in light-injured RPE cells.
ObjectiveTo observe the frequency domain optical coherence tomography (SD-OCT) features of Henle fiber layer (HFL) of health adults in china by changing the angle of the measurement beam. Methods Twenty-four subjects (28 eyes) who showed no abnormalities on routine eye examination were included in the study, including 15 males (16 eyes) and 9 females (12 eyes) with an average age of (35.51±3.54) years old, and mean refraction power of (-0.89±1.15) D. All subjects underwent corrected visual acuity, intraocular pressure, slit lamp microscope, direct ophthalmoscope, visual field and SD-OCT examination. The macular area was scanned by Zeiss Cirrus SD-OCT (5 HD line) single line scan mode. Based on the entry position of the SD-OCT beam through the pupil, the subjects were divided into 3 groups, including group A (center of the pupil), group B (near the temporal edge of the pupil) and group C (near the nasal edge of the pupil). The thickness of outer plexiform layer (OPL), HFL, and outer nuclear layer (ONL) were measured at 0.75 mm, 1.50 mm from the fovea. ResultsWhen entry position of the SD-OCT beam was near the temporal edge of the pupil (group B); there were two layer structures with different signal intensities in the weak reflectivity zones in front of the external limiting membrane (ELM). The signal of the inner layer was slightly higher than the outer layer. The OPL thickness at the decreased side (nasal) increased significantly compared with the other side, but the ONL thickness was significantly thinner than other side. When entry position of the SD-OCT beam was near the nasal edge of the pupil (group C), there were also two layer structures with different signal intensities in the weak reflectivity zones in front of the ELM. The signal of the outer layer was slightly higher than the inner layer. The OPL thickness at the decreased side (temporal) increased significantly compared with the other side, but the ONL thickness was significantly thinner than other side. The OPL thickness at the decreased side was significantly different between these 3 groups (P < 0.01). ConclusionsSD-OCT provided the possibility of distinguishing HFL from the actual ONL by changing the angle of the measurement beam. This finding has great clinical significance for related diseases affecting HFL or ONL.
ObjectiveTo observe the changes in choroidal thickness in type 2 diabetes patients with diabetic retinopathy (DR). MethodsA total of 227 eyes from 150 type 2 diabetes patients were enrolled in this study. The patients included 67 males (89 eyes) and 83 females (138 eyes). The mean age was (65.6±8.0) years, and the mean diabetes duration was (12.4±6.5) years. All the patients were examined for best corrected visual acuity (BCVA), diopter, slit lamp ophthalmoscopy, indirect ophthalmoscopy and spectral domain optical coherence tomography (SD-OCT) examination. The patients were divided into non-DR (NDR group, 99 eyes), non-proliferative DR (PDR) without macular edema (ME) group (NPDR/ME-group, 64 eyes), non-PDR with ME group (NPDR/ME+ group, 5 eyes), PDR without ME group (PDR/ME-group, 25 eyes), PDR with ME group (PDR/ME+ group, 5 eyes) according to the Early Treatment Diabetic Retinopathy Study. The ones having a history of pan-retinal photocoagulation (PRP) were classified as PRP-DR. Age-matched normal subjects were enrolled as the control group. Sub-foveal choroidal thickness (SFCT) was measured by SD-OCT with enhanced depth imaging (EDI). ResultsMean SFCT was (310.2±54.8), (251.1±81.4), (262.5±83.2), (286.2±76.8) and (327.4±83.1) μm respectively in control, NDR, NPDR/ME-, PDR/ME-and PRP-DR groups. Mean SFCT decreased significantly in NDR and NPDR/ME-group (t=2.754, 2.140; P < 0.05). Mean SFCT in PDR/ME-group was thicker than that in NDR (t=-2.114, P < 0.05). Mean SFCT in PRP-DR group was thicker than that in PDR/ME-group (U=271.500, P < 0.05). ConclusionSFCT decreased during the early course of diabetics and increased significantly as the severity worsened from NDR to PDR, and increased in the early duration after PRP treatment.
ObjectiveTo apply the multi-modal deep learning model to automatically classify the ultra-widefield fluorescein angiography (UWFA) images of diabetic retinopathy (DR). MethodsA retrospective study. From 2015 to 2020, 798 images of 297 DR patients with 399 eyes who were admitted to Eye Center of Renmin Hospital of Wuhan University and were examined by UWFA were used as the training set and test set of the model. Among them, 119, 171, and 109 eyes had no retinopathy, non-proliferative DR (NPDR), and proliferative DR (PDR), respectively. Localization and assessment of fluorescein leakage and non-perfusion regions in early and late orthotopic images of UWFA in DR-affected eyes by jointly optimizing CycleGAN and a convolutional neural network (CNN) classifier, an image-level supervised deep learning model. The abnormal images with lesions were converted into normal images with lesions removed using the improved CycleGAN, and the difference images containing the lesion areas were obtained; the difference images were classified by the CNN classifier to obtain the prediction results. A five-fold cross-test was used to evaluate the classification accuracy of the model. Quantitative analysis of the marker area displayed by the differential images was performed to observe the correlation between the ischemia index and leakage index and the severity of DR. ResultsThe generated fake normal image basically removed all the lesion areas while retaining the normal vascular structure; the difference images intuitively revealed the distribution of biomarkers; the heat icon showed the leakage area, and the location was basically the same as the lesion area in the original image. The results of the five-fold cross-check showed that the average classification accuracy of the model was 0.983. Further quantitative analysis of the marker area showed that the ischemia index and leakage index were significantly positively correlated with the severity of DR (β=6.088, 10.850; P＜0.001). ConclusionThe constructed multimodal joint optimization model can accurately classify NPDR and PDR and precisely locate potential biomarkers.