基于改进U-Net的视盘视杯分割方法的研究

基于数字眼底图像进行视盘视杯分割是青光眼常用的诊断方法。为了更加精确地分割视盘视杯,提出了一种基于改进U-Net的视盘视杯分割方法。在传统U-Net的基础上,使用残差块改进了下采样部分,并使用卷积操作改进U-net中的跳层连接部分,使网络更加充分地获取特征信息。使用多种性能指标对训练的模型进行评价,结果表明,视盘模型和...     

Laser-Responsive Shape Memory Device to Program the Stepwise Control of Intraocular Pressure in Glaucoma

There is an unmet need in the glaucoma clinic to control changes in the intraocular pressure (IOP), i.e., patient-specific hypotony and tissue fibrosis-mediated ocular hypertension, owing to the fixed tube diameter of the glaucoma drainage device. As a potential solution, the tube diameter can be adjusted, depending on the IOP, by shape memory polymer (SMP) and clinical laser systems, which can control the energy level, focus, and frequency by minimizing untargeted influences. To develop a translatable device, a laser-responsive SMP with two additional elements: i) a tube with an intimal gel coating to release 5-fluorouracil as an anti-fibrotic drug and ii) a safety lock ring to block late hypotony in special cases is employed. When the SMP tube is inserted into a silicone tube and wrapped externally by the ring, intimal gel degradation and argon laser-triggered diameter increase enable a three-step IOP control. Sustained drug release of the intimal gel suppresses tissue fibrosis, and the ring prevents late hypotony by externally squeezing the silicone tube. The advanced design and functions are validated using computational in vitro and rabbit glaucoma models by determining clinic-friendly argon laser parameters.     

眼压磁力连续测量原理与方法

为解决青光眼患者的24h眼压连续测量问题,提出了一种眼压磁力连续测量原理,采用2个永久磁铁同极靠近产生的排斥力对眼球施加压力,通过求解排斥力-距离曲线上波动点处的压力或波动点后的斜率计算得到眼压值.给出了测量系统结构及其磁排斥力仿真计算结果,对猪眼的实验结果显示,眼内压的大小和排斥力-距离曲线波动点处的压力值存在对应关...     

Improved automated detection of glaucoma by correlating fundus and SD-OCT image analysis

Glaucoma is a multifactorial ocular disease. Ophthalmologists mostly use fundus or optical coherence tomography (OCT) for diagnosis of glaucoma. In this study, a hybrid computer-aided-diagnosis (H-CAD) system has been proposed that integrates both fundus and OCT imaging technologies for reliable diagnosis of glaucoma. Fundus module inspects the outer layer of eye's posterior part. It considers a variety of structural and textural features and makes a decision using support vector machine (SVM). In OCT module, the cup to disc ratio (CDR) has been computed by examining the internal layers of the retina. The cup contour has been extracted from inner-limiting-membrane (ILM) layer using a set of novel techniques for the calculation of cup diameter. Similarly, in the disc diameter calculation the retinal-pigment-epithelium (RPE) layer termination points have been identified by a number of innovative strategies to locate disc margin. Furthermore, a new criterion based on the mean value of RPE-layer end points has been proposed for the determination of cup edges. A local-dataset annotated by four ophthalmologists has been used for evaluation of proposed H-CAD system. The evaluations and results have shown that the final result of H_CAD system is more trustable than its contemporary automated models.     

巩膜池小梁切除术治疗原发性青光眼的疗效

目的探讨巩膜池小梁切除术治疗原发性青光眼的临床疗效。方法将60例（60眼）原发性青光眼患者按不同的手术方法分为3组：A组、B组和C组,每组20例（20眼）。A组行巩膜池小梁切除术,B组行丝裂霉素C（MMC）＋小梁切除术,C组行常规小梁切除术。术后随访1周,3、6、12、24个月;观察3组患者术后眼压、滤过道大小、视野的变化及有无并发症发生等情况。结果 A、B 2组术后3、6、12、24个月眼压均明显低于C组（均P〈0.05）。术后24个月,A、B 2组功能性滤过泡所占比例与C组比较差异均有统计学意义（均P〈0.05）,A组以Ⅱ型滤过泡为主,B组以I型滤过泡为主,C组Ⅲ型滤过泡为主;B、C 2组滤过道（减压室）值与A组比较差异均有统计学意义（均P〈0.05）;A、C 2组角膜上皮损伤、前房积血、滤过泡漏、前葡萄膜炎发生率均明显低于B组（P〈0.05或P〈0.01）,B、C 2组浅前房发生率均明显低于A组（均P〈0.05）。结论巩膜池小梁切除术能有效增加滤过道的大小,充分发挥减压功效,并能长期、有效控制眼压,且并发症少。     

Role of Choline in Ocular Diseases

Choline is essential for maintaining the structure and function of cells in humans. Choline plays an important role in eye health and disease. It is a precursor of acetylcholine, a neurotransmitter of the parasympathetic nervous system, and it is involved in the production and secretion of tears by the lacrimal glands. It also contributes to the stability of the cells and tears on the ocular surface and is involved in retinal development and differentiation. Choline deficiency is associated with retinal hemorrhage, glaucoma, and dry eye syndrome. Choline supplementation may be effective for treating these diseases.     

An Ultrasensitive Contact Lens Sensor Based On Self-Assembly Graphene For Continuous Intraocular Pressure Monitoring

Elevated intraocular pressure (IOP) is the leading cause of glaucoma. As glaucoma is an irreversible neurological eye disease, it is urgent to realize timely and accurate IOP detection for diagnostic and therapeutic purposes. Here, a contact lens sensor for continuous IOP monitoring using self-assembly graphene (SAG), is developed. The combination of face-to-face water transfer printing and micro-electromechanical systems technology can realize the batch preparation of such a sensor. The sensor has good light transmittance and temperature stability. It exhibits an ultra-high IOP sensitivity of 1.0164 mV mm Hg⁻¹ on a silicone eye, and 3.166 mV mm Hg⁻¹ in vitro on the porcine eye with remarkable linearity. The sensitivity of the proposed sensor is high enough to be read by a commercial radio frequency identification read–write system for continuous wireless monitoring of IOP. Furthermore, the as-prepared sensor can work as normal for 24 h in phosphate buffer saline.     

视盘和视杯分割在计算机辅助青光眼诊断中的应用综述

青光眼是以视神经损伤、特征性视野损伤为特点的一类眼病,在早期很难诊断,尽早发现可更好地遏制青光眼病症的恶化,降低致盲率。视盘和视杯的比值是评价青光眼诊断中的重要指标之一,视盘和视杯的分割是青光眼诊断的关键步骤。但眼底彩照中的渗出物、不均匀照明区域等特征使其可能出现相似的亮度区域,导致视盘和视杯的分割非常困难。因此本文对现有眼底彩照中视盘和视杯的分割方法进行了总结,并将其分为5大类:水平集法、模态法、能量泛函法、划分法以及基于机器学习的混合法。系统地梳理了各类算法的代表性方法,以及基本思想、理论基础、关键技术、框架流程和优缺点等。同时,概括了适用于青光眼诊断的各种数据集,包括数据集的名称、来源以及详细内容,并总结了在各种数据集中不同视盘和视杯分割结果和诊断青光眼的量化指标及其相关结果。在现有的视盘和视杯分割方法中,许多图像处理和机器学习技术得到广泛应用。通过对该领域研究算法进行综述,清晰直观地总结了各类算法之间的特点及联系,有助于推动视盘和视杯分割在青光眼疾病临床诊断中的应用。可以在很大程度上提高临床医生的工作效率,为临床诊断青光眼提供了重要的理论研究意义和价值。     

Vitamin D and Ocular Diseases: A Systematic Review

The contributory roles of vitamin D in ocular and visual health have long been discussed, with numerous studies pointing to the adverse effects of vitamin D deficiency. In this paper, we provide a systematic review of recent findings on the association between vitamin D and different ocular diseases, including myopia, age-related macular degeneration (AMD), glaucoma, diabetic retinopathy (DR), dry eye syndrome (DES), thyroid eye disease (TED), uveitis, retinoblastoma (RB), cataract, and others, from epidemiological, clinical and basic studies, and briefly discuss vitamin D metabolism in the eye. We searched two research databases for articles examining the association between vitamin D deficiency and different ocular diseases. One hundred and sixty-two studies were found. There is evidence on the association between vitamin D and myopia, AMD, DR, and DES. Overall, 17 out of 27 studies reported an association between vitamin D and AMD, while 48 out of 54 studies reported that vitamin D was associated with DR, and 25 out of 27 studies reported an association between vitamin D and DES. However, the available evidence for the association with other ocular diseases, such as glaucoma, TED, and RB, remains limited.     

Synthesis and Biological Evaluation of 4‐Sulfamoylphenyl/Sulfocoumarin Carboxamides as Selective Inhibitors of Carbonic Anhydrase Isoforms hCA II,IX, and XII

With the aim to develop potent and selective human carbonic anhydrase inhibitors (hCAIs), we synthesized 4‐sulfamoylphenyl/sulfocoumarin benzamides (series 5 a – r and series 7 a – q ) and evaluated their inhibition profiles against five isoforms of the zinc‐containing human carbonic anhydrase (hCA, EC 4.2.1.1): cytosolic hCA I and II, and the transmembrane isozymes hCA IV, IX, and XII. Compounds 5 a – r were found to selectively inhibit hCA II in the nanomolar range, while being less effective against the other hCA isoforms. As noted from the literature, sulfocoumarin (1,2‐benzoxathiine 2,2‐dioxide) acts as a “prodrug” inhibitor and is hydrolyzed by the esterase activity of hCA to form 2‐hydroxyphenylvinylsulfonic acid, which thereafter binds to the enzyme in a manner similar to that of coumarins and sulfoxocoumarins. All these sulfocoumarins (compounds 7 a – q ) were found to be very weak or ineffective as inhibitors of the housekeeping off‐target hCA isoforms I and II, and effectively inhibited the transmembrane tumor‐associated isoforms IX and XII in the high nanomolar to micromolar ranges. Further structural modifications of these molecules could be useful for the development of effective hCA inhibitors used for the treatment of glaucoma, epilepsy, and cancer.