Glaucoma is the leading cause of irreversible blindness, but its early symptoms are not obvious and are easily overlooked, so early screening for glaucoma is particularly important. The cup to disc ratio is an important indicator for clinical glaucoma screening, and accurate segmentation of the optic cup and disc is the key to calculating the cup to disc ratio. In this paper, a full convolutional neural network with residual multi-scale convolution module was proposed for the optic cup and disc segmentation. First, the fundus image was contrast enhanced and polar transformation was introduced. Subsequently, W-Net was used as the backbone network, which replaced the standard convolution unit with the residual multi-scale full convolution module, the input port was added to the image pyramid to construct the multi-scale input, and the side output layer was used as the early classifier to generate the local prediction output. Finally, a new multi-tag loss function was proposed to guide network segmentation. The mean intersection over union of the optic cup and disc segmentation in the REFUGE dataset was 0.904 0 and 0.955 3 respectively, and the overlapping error was 0.178 0 and 0.066 5 respectively. The results show that this method not only realizes the joint segmentation of cup and disc, but also improves the segmentation accuracy effectively, which could be helpful for the promotion of large-scale early glaucoma screening.
At present, there are few in vivo experimental studies on anterior chamber flow field, and the relevant technologies are not mature. This study explores the experimental method and key techniques of particle image velocimetry (PIV) for the in vivo measurement of anterior chamber flow field with slow flow velocity in the rabbit with acute intraocular hypertension. The experimental process can be divided into three parts: model construction of rabbit eye with acute intraocular hypertension, in vivo eyeball preparation, and PIV setup. The following key techniques were mainly investigated: the optimal injection strategy of fluorescent particles and the correction strategy for image acquisition errors caused by the effects of image refraction and respiration. The results showed that the best injection method was that 15 μL of fluorescent particles solution was slowly injected into the anterior chamber through the lower part of iris and then the rabbit was released and waited for 13 h. In this way particles were completely distributed in the anterior chamber with the help of the aqueous humor circulation, and then in vivo PIV experiment could be performed. The eyeball should be covered with a square flume filled with ultrasonic coupling gel for the sake of imaging during the experiment. The Maximal Information Coefficient algorithm could be applied to correct the measured results before post-processing calculation. The results indicated that feasible injection strategy of fluorescent particles and the correction strategy for image acquisition are critical to obtain nice experiment effects for the in vivo PIV measurement of anterior chamber flow field in the rabbit with acute intraocular hypertension.
ObjectiveTo systematically review the diagnostic value of optical coherence tomography angiography (OCTA) for primary open-angle glaucoma (POAG). MethodsThe CNKI, WanFang Data, VIP, CBM, PubMed, Embase, Web of Science, and Cochrane Library databases were electronically searched to collect diagnostic test on OCTA for POAG from inception to February 2024. Two reviewers independently screened literature, extracted data and assessed the risk of bias of the included studies. Meta-analysis was then performed by using Stata 15.0 software. ResultsA total of 12 diagnostic tests involving 993 subjects were included. Meta-analysis results showed that the sensitivity/specificity of OCTA for diagnosing peripapillary vessel density, retinal vessel density, and optic nerve fiber changes in patients with POAG were 0.77/0.92, 0.56/0.92, and 0.85/0.91, respectively, and the AUC of the SROC curve was 0.94, 0.92 and 0.95, respectively. ConclusionOCTA has high diagnostic accuracy for POAG. Due to the limited quality and quantity of the included studies, more high quality studies are needed to verify the above conclusion.
ObjectiveTo systematically review the association between myopia and open-angle glaucoma (OAG). MethodsForeign and domestic articles published from January 2000 to May 2013 were searched in PubMed, EMbase, WanFang Data, VIP and CNKI for observational studies on the association between myopia and OAG. According to the inclusion and exclusion criteria, the studies were screened, the data were extracted, and the method quality of included studies was assessed. Then meta-analysis was performed using Stata 12.0 software. ResultsEleven cross-sectional studies including 45 996 participants were finally included. The results of meta-analysis showed that, myopia increased the risk of OAG. Besides, the results of subgroup analysis by the severity of myopia showed that, low-degree myopia (more than-3.00 D) increased 1.52 times the risk (OR=1.52, 95%CI 1.23 to 1.88) while middle/high-degree myopia (no more than-3.00 D) increased 2.41 times (OR=2.41, 95%CI 1.91 to 3.03). ConclusionIndividuals with myopia have increased risk of OAG.
Objective To assess the efficacy and safety of a dorzolamide/timolol combination versus latanoprost in the treatment of open-angle glaucoma. Method We searched for randomized control trials concerning a dorzolamide/timolol combination versus latanoprost in the treatment of open-angle glaucoma,in electronic databases , and handsearched some related journals. The quality was evaluated and meta-analysis was conducted using the software RevMan 5.0. Results Six randomized control trials involving 361 patients and 361 eyes were identified. The Meta-analysis showed that at the end of study, there was a statistically significant difference between the two study groups with WMD – 0.49, and 95%CI – 1.06 to 0.07 ( P=0.09) in lowering intraocular pressure; there was no statistically significant difference between the two groups with WMD 1.43 and 95%CI 0.49 to 4.21 (P=0.53); and there was no statistically significant differences between the two groupswith WMD 0.40 and 95%CI 0.13 to 1.26 (P=0.12) in incidence of headache. Conclusion Compared with latanoprost, dorzolamide-timolol combination have increased efficacu in lowering intraocular pressure (IOP).If we want a more reliable result ,we need a large number of multi-centre,double-blinded randomized control trials.
Poly(styrene-block-isobutylene-block-styrene) (SIBS) and its crosslinked product crosslinked polyisobutylene (xPIB) are a kind of novel thermoplastic elastomer. They have excellent biocompatibility and stability, which are suitable for long-term implantation in human body. At present, SIBS is widely used in cardiovascular diseases, and also has preliminary application in ophthalmology. This article reviews the application and research progress of SIBS and xPIB in ophthalmic glaucoma minimally drainage tube material, intraocular lens material, new sclera buckle material and orbital defect filler, with a view of providing reference for the clinical application of such biomedical materials in ophthalmology.
Objective To investigate the efficacy and prognostic factors of pars plana vitrectomy (PPV) in the treatment of proliferative diabetic retinopathy (PDR) with chronic renal failure (CRF). MethodsA retrospective study. From January 2016 to June 2021, a total of 82 eyes of 58 patients diagnosed with PDR combined with CRF and treated with PPV in Department of Ophthalmology, The Second Hospital of Hebei Medical University were included in the study. There were 32 cases in males and 26 cases in females. The mean age was (48.45±10.41) years. The course of renal failure was (4.15±3.23) years, and the course of diabetes was (14.45±6.71) years. All patients undergo best-corrected visual acuity (BCVA). The BCVA examination was performed using the international standard Snellen visual acuity chart, which was converted to logarithm of the minimum angle of resolution (logMAR) visual acuity for recording. The mean number of logMAR BCVA was 2.04±0.82 (0.7-2.8). The duration of vitreous hemorrhage averaged (2.65±1.55) months. There were 38 eyes (46.3%, 38/82) with traction retinal detachment; 32 eyes had a history of panretinal photocoagulation (PRP) treatment (39.0%, 32/82). All eyes were treated with 25G PPV. Patients with traction retinal detachment were treated with intravitreal injection of anti-vascular endothelial growth factor (VEGF) 3 days before surgery. Opacification of the lens affected the operation operator combined with phacoemulsification. Biochemical indexes such as hemoglobin, glycosylated hemoglobin, albumin, creatinine, uric acid, and alternative treatment (non-dialysis/hemodialysis/peritoneal dialysis) were collected. Postoperative follow-up time was ≥6 months. χ2 test or Fisher's exact test were used for comparison between groups. A logistic regression model was used for multivariate analysis, and Spearman correlation analysis was used to evaluate the correlations between variables. ResultsAt 6 months after surgery, the mean logMAR BCVA was 1.16±0.57. Compared with logMAR BCVA before surgery, the difference was statistically significant (t=－0.837, P＜0.001); 44 eyes had BCVA ≥0.1 and 38 eyes had BCVA ＜0.1. Postoperative vitreous hemorrhage (PVH) was observed in 17 eyes after surgery (20.7%, 17/82). PVH occurred in 15 (46.9%, 15/32), 1 (2.3%, 1/44), and 1 (16.7%, 1/6) eyes in patients without dialysis, hemodialysis and peritoneal dialysis, respectively. There was significant difference between those without dialysis and those on hemodialysis (χ2=26.506, P＜0.05). There was no significant difference between peritoneal dialysis patients and those without dialysis and hemodialysis patients (χ2=2.694, 2.849; P＞0.05). PVH occurred in 3 (10.0%, 3/30) and 14 (27.0%, 14/52) eyes of vitreous cavity filled with silicone oil and perfusion fluid, respectively. The difference was statistically significant (χ2=3.315, P＜0.05); 1 (33.3%, 1/3) and 10 (71.4%, 10/14) eyes were treated with PPV again, respectively, and the difference was statistically significant (P＜0.05). Neovascular glaucoma (NVG) occurred in 12 eyes (14.6%, 12/82). Logistic regression analysis showed that age [odds ratio (OR) =0.911, P＜0.05], diabetic retinopathy (DR) stage (OR=7.229, P＜0.05), renal failure duration (OR=0.850, P＜0.05), operation time (OR=1.135, P＜0.05) was an independent risk factor for poor vision prognosis. Diabetes duration (OR=1.158, P＜0.05), renal failure duration (OR=1.172, P＜0.05) and alternative therapy were independent factors affecting the occurrence of PVH. Diabetes duration (OR=1.138, P＜0.05) and renal failure duration (OR=1.157, P＜0.05) were independent risk factors for postoperative NVG. Spearman correlation analysis showed that PVH was strongly correlated with post-operative NVG (r=0.469, P＜0.01). There was no significant correlation between blood glucose, hemoglobin, creatinine and blood urea nitrogen and prognosis of postoperative vision, PVH and NVG occurrence (P＞0.05). ConclusionsIn PDR patients with CRF, DR Stage, age, renal failure course and operation duration are correlated with vision prognosis. Compared with those who do not receive alternative therapy, hemodialysis treatment can reduce the occurrence of PVH and NVG after surgery.
Objective To study prospectively the morphological relations among hemorrhage of optic disc, defect of retinal nerve fiber layer, and peripapillary atrophy in normal-tension glaucoma (NTG). Methods Qualitative and quantitative methods were applied to evaluate the relations among hemorrhage of optic disc, defect of retinal nerve fiber layer, and peripapillary atrophy by using stereo ocular fundus photography and computer analyzer systems. Results In 37 patients (42 eyes) in NTG hemorrhage group, 50 hemorrhagic spots at optic disc was found, including coloboma of retinal nerve fiber layer in 35 eyes (83.3%)(35/42). In 35 patients (40 eyes) in non-hemorrahge group, partial coloboma of retinal nerve fiber layer was found in 21 eyes (52.5%)(21/40). The difference of incidence of coloboma of retinal nerve fiber layer between the two groups was not significant (chi;2=1.403, P=0.236). The incidence of atrophic arc in hemorrhage group differed much from which in non-hemorrhage group (chi;2=7.008, P=0.008). The area of atrophic arc at beta;section in hemorrhage group ［(2.05plusmn;0.88)mm2］ was significantly different from which in non-hemorrhage group［(1.42plusmn;0.53)mm2］(t=-2.618, P=0.012). In the follow-up period, the difference of incidence of disc-rim loss between hemorrhage and non-hemorrhage group was significant, (chi;2=5.802, P=0.016); while the difference of the incidence of visual field defect between the two groups was not. Conclusion In eyes with NTG, hemorrhage of optic disc, coloboma of retinal nerve fiber layer and atrophic arc are closely related. More disc-rim loss and changes of atrophic-arc area in hemorrhage group in the follow-up period suggests that hemorrhage of optic disc is the risk factor of development of NTG. (Chin J Ocul Fundus Dis, 2006, 22: 232-235)
ObjectivesTo systematically review the association between the SIX6 gene rs10483727 mutation and primary open angle glaucoma (POAG).MethodsPubMed, Web of Science, The Cochrane Library, CNKI, WanFang Data and VIP databases were searched to collect case-control studies on the SIX6 gene rs10483727 polymorphism and primary open angle glaucoma from inception to December 28th, 2018. Two reviewers independently screened literature, extracted data and assessed the risk of bias of included studies. Meta-analysis was performed by Stata 12.0 software.ResultsSeventeen case-control studies in 16 papers were included, involving 9 886 patients and 19 663 controls. The results of meta-analysis showed that rs10483727 polymorphism in SIX6 gene was associated with the risk of POAG in the Asians and Caucasians. However, no association was found in the Africans.ConclusionsThe current evidence shows that rs10483727 polymorphism in SIX6 gene is associated with the risk of POAG in the Asians and Caucasians.
ObjectiveTo systematically review the efficacy and safety of phacoemulsification combined with trabeculectomy versus simple phacoemulsification for primary angle closure glaucoma with cataract.MethodsDatabases including PubMed, EMbase, The Cochrane Library, CBM, CNKI, VIP and WanFang Data were searched to collect randomized controlled trials (RCTs) about phacoemulsification combined with trabeculectomy vs. simple phacoemulsification for primary angle closure glaucoma with cataract from inception to May 2017. Two reviewers independently screened literature, extracted data and assessed the risk of bias of included studies. Then meta-analysis was conducted by RevMan 5.3 software.ResultsA total of eight studies involving 679 patients were included. The results of meta-analysis showed that: there were no significant differences between two groups in postoperative visual acuity (MD=0.00, 95%CI –0.10 to 0.09, P=0.98), postoperative anterior chamber depth (MD=0.14, 95%CI –0.17 to 0.45, P=0.37) and adverse reactions rates (optic nerve injury: RR=1.56, 95%CI 0.70 to 3.47, P=0.28; visual field defect: RR=1.43, 95%CI 0.70 to 2.92, P=0.33; corneal edema: RR=0.57, 95%CI 0.25 to 1.32, P=0.19).ConclusionCurrent evidence shows that phacoemulsification combined with trabeculectomy and simple phacoemulsification has the similar efficacy and safety for primary angle closure glaucoma with cataract. Due to limited quantity and quality of the included studies, the above conclusions still need to be verified by more high quality studies.