Study on Stereometric Parameters of Optic Nerve Head of Normal, Big-cupped Disk and Glaucomatous Eyes Using Heidelberg Retina Tomograph

Purpose: To investigate the difference of stereometric parameters of optic nerve head between the normal subjects and patients with big-cupped disk and primary open angle glaucoma (POAG).Methods: Twenty-two cases (44 eyes) of normal subjects, 17 cases (34 eyes) of patients with big-cupped disk and 19 cases (37 eyes) of patients with POAG underwent Heidelberg Retina Tomograph (HRT) examination to get topography images and stereometric parameters of optic nerve head.Results: The stereometric parameters of optic nerve head of the normal, patients with big-cupped disk and POAG were 1) disk area (mm2): 1. 995± 0. 501, 2. 407±0. 661 and 2. 248±0.498; 2) cup area (mm2): 0.573±0.264, 1. 095±0. 673 and 1. 340±0. 516; 3) cup/disk ratio: 0. 25±0. 095, 0. 428±0. 176 and 0. 589±0.195; 4) rim area (mm2): 1.461±0.328, 1.312±0.418 and 0. 905± 0.409; 5)cup volume (mm3): 0. 108±0. 073, 0. 347±0. 346 and 0. 550 ±0. 394; 6) rim volume (mm3): 0. 421±0. 111, 0. 378±0. 225 and 0. 224±0. 189; 7) mean cup

Role of Retinal Nerve Fiber Layer Thickness and Optic Disk Measurement by OCT onEarly Diagnosis of Glaucoma

Purpose:.Glaucoma is an eye disease that can lead to irreversible optic nerve damage and cause blindness. Optical coherence tomography.(OCT) allows an early diagnosis of glaucoma by the measurements of the retinal nerve fiber and optic disc parameters.A retrospective study was designed to analyze the effects of the measurement of the retinal nerve fiber layer(RNFL) thickness and the optic disc tomography by spectraldomain OCT on the early diagnosis of suspected glaucoma and primary open angle glaucoma(POAG).Methods:.This was a clinical case-control study. The RNFL thickness around the optic disc and optic disk tomographic parameters of the control(n=51, 98 eyes), suspected glaucoma(n=81,.146 eyes), and POAG groups(n=55, 106 eyes) were measured by OCT. The parameters included superior, inferior, nasal and temporal mean RNFL thickness,.disc area(DA), cup area(CA), rim area(RA), disc volume(DV),cup volume(CV), rim volume(RV), cup / disc area ratio(CA / DA), rim / disc area ratio(RA / DA), cup / disc volume ratio(CV / DV) and rim / disc volume ratio(RV / DV).Results: Superior, nasal, and mean RNFL parameters, DA,CA,RA, DV, CV, CA / DA, RA / DA, CV / DV and RV / DV significantly differed among three groups by single-factorial ANOVA. Inferior and temporal RNFL thickness significantly differed between the control and POAG groups. No significant difference was observed in RV among three groups. In the POAG group,.the maximum area under the ROC curve(AROC) of mean RNFL thickness was 0.845. The maximum AROC of optic disk parameters was RA / DA(0.998), followed by CA / DA(0.997). The AROC of CA, RA, CV, and DV were all > 0.900.Conclusion:.OCT may serve as a useful diagnostic modality in distinguishing suspected glaucoma from POAG.

Detection of Influenza Viruses Attached to an Optical Disk

Detection of polystyrene beads with a diameter of 100 nm was conducted using an optical disk drive tester equipped with a laser of 405 nm wavelength and an objective lens with a numerical aperture of 0.65. The polystyrene beads were used to mimic the influenza virus. A grooved disk with a (ZnS)85(SiO2)15/SiO2 layered surface structure was used for the detection. The detection of influenza viruses (A/Udorn/307/1972) with Au nanoparticles was also demonstrated using the optical disk drive tester. In this case, a grooved disk with an indium tin oxide (ITO) film was used. The ITO film functioned both to tune the reflectance of the disk and as an electrically conductive layer for scanning electron microscopy. In both cases, the target substances were successfully recognized in a single scan with a high scanning speed of 4.9 m/s. The results indicate that this optical disk system can be used to detect 100 nm scale substances like influenza viruses, which are smaller than the diffraction limit of the system.

Magneto-optical Disk Material for Improving the Density of Information Storage

This paper introduces the fundamental principle and features ofmagneto-optical storage technol- ogy, and discuses the trend and aseries of key techniques for increasing the data storage density ofmagneto-opti- cal disk. The three ways including MO media, recordingmethod and readout method for increasing the disk ca- pacity havebeen discussed. Moreover, the importance with the exchange-coupledeffect between the magnetic layers and recording domain morphology isemphasized.

超广角光学相干断层扫描血管成像在视网膜静脉阻塞诊断中的应用

目的探讨超广角光学相干断层扫描血管成像(OCTA)在视网膜静脉阻塞(RVO)患者诊断中的价值。方法选取2023年1月至2024年1月在西安爱尔古城眼科医院接受检查并确诊的RVO患者78例(78眼)进行回顾性研究,其中男43例、女35例,年龄(58.7±9.4)岁。所有患者均于2周内分别接受超广角OCTA、荧光素眼底血管造影(FFA)检查,以FFA检查结果作为临床诊断金标准,计算超广角OCTA对视网膜无灌注区的诊断价值。采用配对t检验分析受检者患侧与健侧超广角OCTA检查的视盘区血流密度特征参数差异;采用方差分析法分析FFA与超广角OCTA检查无灌注区面积的差异。结果超广角OCTA检查视网膜层、浅层血管复合体、深层血管复合体无灌注区面积与FFA检出的无灌注区面积比较,差异均无统计学意义(均P>0.05)。视网膜中央静脉阻塞患者患侧视盘区整个图像血管、视盘周血管、整个图像毛细血管、视盘周毛细血管、下方鼻侧、下方颞侧、颞下、颞上、上方颞侧、下方颞侧血流密度均低于健侧[(50.61±4.82)%比(55.17±5.20)%、(51.40±4.77)%比(57.37±5.00)%、(45.68±5.20)%比(48.93±4.88)%、(45.48±5.50)%比(50.30±6.23)%、(43.83±5.50)%比(48.29±7.23)%、(50.90±7.27)%比(57.34±7.86)%、(48.65±6.61)%比(53.43±6.93)%、(49.50±6.14)%比(54.63±7.22)%、(49.33±7.10)%比(55.38±7.50)%、(45.52±6.14)%比(49.58±6.85)%],差异均有统计学意义(均P<0.05)。视网膜分支静脉阻塞患者患侧视盘区整个图像血管、视盘周血管、整个图像毛细血管、视盘周毛细血管、下方鼻侧、下方颞侧、颞下、颞上、上方颞侧、下方颞侧血流密度均低于健侧[(52.33±5.14)%比(55.43±4.88)%、(52.30±5.15)%比(57.43±4.86)%、(46.77±4.98)%比(49.54±5.50)%、(46.13±6.62)%比(50.63±5.87)%、(44.18±5.87)%比(48.43±6.61)%、(51.39±6.98)%比(57.92±6.94)%、(49.66±6.21)%比(53.56±6.60)%、(49.50±6.33)%比(54.81±6.87)%、(49.89±7.09)%比(56.12±7.28)%、(45.83±5.81)%比(50.75±6.43)%],差异均有统计学意义(均P<0.05)。超广角OCTA检查诊断视网膜中央静脉阻塞及视网膜分支静脉阻塞患者无灌注区的灵敏度分别为100.0%(35/35)、81.4%(35/43),特异度分别为86.0%(37/43)、100.0%(35/35)。结论超广角OCTA可检查RVO患眼视盘区血流密度特征,对RVO无灌注的诊断价值较高,且与FFA相比具有无创优势。

Multiple-State Storage Capability of Stacked Chalcogenide Films （Si16Sb33Te51/Si4Sb45Te51/Si11Sb39Te50） for Phase Change Memory

The multiple-state storage capability of phase change memory （PCM） is confirmed by using stacked chalcogenide films as the storage medium. The current-voltage characteristics and the resistance-current characteristics of the PCM clearly indicate that four states can be stored in this stacked film structure. Qualitative analysis indicates that the multiple-state storage capability of this stacked film structure is due to successive crystallizations in different Si-Sb-Te layers triggered by different amplitude currents.

Optical fluence compensation for handheld photoacoustic probe:An in vivo human study case

Integrating photoacoustic(PA)and ultrasound(US)into a handheld probe to perform P A/US dual-modal imaging has been widely studied over the past few years.However,optical fuence decreases quickly in deeper tissue due to light scattering and absorption,which would signifi-cantly affect the quantitative PA imaging.In this paper,we performed a fluence compensation for a PA imaging study of human breast.The comparison of P A/US image with and without optical fuence compensation demonstrated that the fuence compensation could effectively improve imaging quality for handheld probe.

EFFECTS OF SPUTTERING CONDITIONS OF Tb Fe Co MAGNETO OPTICAL FILM ON KERRR OTATION

In the practical magneto opticaldisk productionline,alloysputteringtargetisalwaysusedtosputter recording film , whileinlaid targetisrarely used .In ourlaboratory,a seriesof al loy targets forsputtering magneto- optical recording film were prepared and theeffect ofcomposition andsputtering parameterson magneto opticalpropertiesarestudied . Thesputter ing rateof Al,Siand Tb Fe Co( Mo) undertheconditionsof differentsputtering powerandN2 Argasflux weredetermined and baseontheresults,a variablecomposition andthickness of SiNcan beobtained by meansof regulating sputtering power and gasflux, kindsof Mosputtering filmsareobtained under differentsputtering power and gasflux, and Kerrloop lineofthese magneto opticalfilmsare measuredto acquiretheir propertiessuch as Kerrrota tion,then ,theeffectofsputteringtechnology on Kerrrotationisdiscussed .

Spectral Parameters of Nd^(3+)∶Sr_6YSc(BO_3)_6

The crystal Nd 3+∶Sr 6YSc(BO 3) 6 was grown by the top-seeded solution growth method from a Li 6B 4O 9 flux. The s pectral properties of Nd 3+∶Sr 6YSc(BO 3) 6 crystal were investigated. Using Judd-Ofelt theory to ana lyze the optical strength measured in absorption spectrum, the following spectr al parameters were obtained: parameters of oscillator strengths Ω λ are Ω 2=1.194×10 -20 cm2, Ω 4=4.186×10 -20 cm2 and Ω 6=3.3 51×10 -20 cm2. The radiative lifetime is 322 μs, and the fluorescence b ranch ratios were calculated: β 1=0.465, β 2=0.453, β 3=0.079 and β 4=0.004. The results indicate that Nd 3+∶Sr 6YSc(BO 3) 6 c rystal seems to be a potential high-efficient laser material.

Optical coherence tomography in optic disc drusen

Optic disc drusen (ODD) are hyaline deposits in the optic nerve head, occurring in approximately 2% of the population. ODD may be superficial and visible, or buried and either invisible or seen only as elevation of the optic disc, mimicking optic disc edema. Advanced optic nerve imaging, including optical coherence tomography (OCT) can be used to diagnose and characterize ODD with very high resolution. Enhanced depth imaging (EDI-OCT) in particular has emerged as the optimal modality to directly visualize ODD. This modality has led to a greater ability to differentiate ODD from optic disc edema and prevent misdiagnosis or invasive testing. We review the characteristic findings of ODD on OCT, their distinguishing features, and the use of OCT as a biomarker in the neuro-ophthalmic assessment of ODD.

基于ReSE-AG-Net的青光眼视盘视杯分割方法

分割视盘视杯是诊断青光眼的主要依据,因此提出了一种基于改进U-Net网络的青光眼视盘视杯分割方法,称为ReSE-AG-Net。并将ReSE-AG-Net、U-Net、M-Net、CE-Net和CDED-Net分别在Drishti-GS1数据集和RIM-ONE-R3数据集上进行测试,对得到分割后的视盘视杯的Dice系数和IoU进行对比。实验结果表明,在Drishti-GS1数据集上,分割视盘的Dice系数和IoU分别是0.989 1和0.959 0,分割视杯的Dice系数和IoU分别是0.931 0和0.871 0,在RIMONE-R3数据集上,分割视盘的Dice系数和IoU分别是0.978 9和0.958 7,分割视杯的Dice系数和IoU分别是0.863 7和0.760 1,对比U-Net模型和现有的分割模型均有一定的提升,证明了该方法的可行性。

Aggregation-induced emission (AIE) luminescent materials boosting optical storage into the new era of petabit-level capacity

The recording of information stands as the most significant milestone in human civilization.Historically,the recording and storage of information have undergone a technological evolution from paintings to carvings,scribing,and digitization.The invention of optical compact discs(CDs)was one of the major landmarks in digital information technology.Over the past half-century,scientists have endeavored to enhance optical storage capacity by improving both optical systems and optical storage materials,as shown in Scheme 1.In terms of commercial products,the storage capacity has increased from 700 MB(CDs)to 27 GB(Blu-ray discs)by optimizing the optical system based on the same optical storage medium(polycarbonate).To surpass the conventional optical diffraction limit,the optical systems have evolved from traditional lasers to nonlinear two-photon absorption(TPA)and stimulated emission depletion(STED),which has minified the laser spot size from microns to approximately tens of nanometers,marking a remarkable achievement.

Rastall gravity:accretion disk image in the context of radiation fields and visual transformations compared to Reissner-Nordström black hole

In this study,we investigated the astronomical implications of Rastall gravity,particularly its behavior amidst a radiation field compared to Reissner-Nordström(RN)black holes.We found a crucial correlation between the dynamics of the accretion disk and the parameters Q and Nr,which properly reflect the influence of spacetime metrics on the disk’s appearance.Elevated electric charge Q causes contraction in the disk’s orbit due to enhanced gravitational effects,while higher Nr values lead to outward expansion,influenced by the attributes of the radiation field.Interestingly,the charged black holes surrounded by radiation fields exhibit distinct visual disparities from RN black holes.Brightness decreases and expansion occurs within the innermost stable circular orbit of the accretion disk with rising Nr values.Our study also reveals the process by which the accretion disk transitions from a conventional disk-like structure to a hat-like form at different observation angles,with the redshift effect gradually intensifying.Moreover,the results of the considered Rastall gravity radiation field are consistent with the constraints of the gravitational lensing of the host galaxy on Rastall gravity parameters,thereby enhancing the consistency between theoretical predictions and actual observations.

近视病人青光眼诊断的研究进展

近视是青光眼发病的高危因素,且研究表明近视程度越高,患青光眼的可能性就越大。近视病人青光眼诊断是一个特殊问题,这可能因为早期青光眼与近视的表现相似,所以许多近视病人因青光眼而使视力受到损害,但未引起临床医生考虑青光眼的可能性。近年来随着眼科影像技术的发展,尤其是光学相干断层扫描与共焦激光眼底扫描红外成像及无赤光眼底照相技术的结合、光学相干断层扫描离散傅里叶变换分析与视野的结合,光学相干断层扫描血流成像的快速革新,临床医生可以从多方面了解近视与青光眼的发生发展,为早期诊断近视眼青光眼,及时干预治疗,从而为提高近视病人的视觉生活质量提供坚实的基础。

基于CD/DVD光盘的光波衍射研究

白炽灯光入射在CD/DVD光盘会呈现随着角度轻微变化发生相应变化的彩色线.基于CD/DVD光盘的制造工艺,利用MATLAB软件对衍射规律进行理论分析,使用分光计实验观察白炽灯照射下CD/DVD光盘呈现出彩色线的衍射现象,验证不同入射角、衍射角、水平偏转角与波长的关系,获得不同条件下的衍射图案.为光学和材料科学等多个学科领域以及数字储存技术的发展提供新的思路和方向.

关于光盘上出现彩色线的实验研究

为了探究光盘(CD或DVD)的光栅衍射规律,以2023年全国大学生物理学术竞赛“色彩线”这一题为例,从理论与实验两方面研究光盘在有无刻录、不同的刻录方式、不同的光路入射角度等条件下衍射条纹颜色的变化情况,探究光盘上光栅衍射规律。结果表明:光盘上衍射条纹颜色与光盘结构、入射光角度和光盘倾角有关。该研究对新型光盘材料和技术的开发有着一定的理论和实践意义。

曲安奈德玻璃体腔注射治疗视盘血管炎的临床观察

目的评估玻璃体腔注射曲安奈德(TA)治疗视盘血管炎(ODV)的疗效。方法43例ODV患者玻璃体腔内注射TA4mg,注药前后分别测矫正视力、视野、眼底及光学相干断层成像(OCT)。结果注药后患者视力明显提高(P<0.01),ODV相关黄斑水肿显著减轻(P<0.01)。结论TA玻璃体腔注射是治疗ODV的有效方法。

聚碳酸酯光学性能应用及改进研究进展

概述了光学级聚碳酸酯结构与光学性能的关系和其在光学领域的应用,对其光学异向性产生的原因进行了讨论,并对改善聚碳酸酯光学异向性的途径进行了归纳,通过采用共聚、共混方法可使聚碳酸酯的双折射得到有效的降低。

彩色眼底图像视盘自动定位与分割

针对彩色眼底图像视盘定位时图像边缘高亮环对定位准确率的影响,提出了一种有效的图像预处理方法。针对已有的视盘分割算法中存在的问题,提出了一种结合形态学、椭圆拟合及梯度矢量流(GVF)Snake模型的分割算法。提出的预处理方法首先利用最小二乘法拟合出眼底图像的边界,然后裁剪掉边界的一部分高亮像素点,最后进行视盘定位。视盘分割算法则首先进行血管擦除,然后用椭圆拟合提取初始轮廓,最后使用GVF Snake精确调整视盘边界。用提出的方法对Messidor眼底图像数据库1 200幅图像上进行了实验,结果显示:视盘定位准确率由原来没经过预处理的95.4%提升到了98.7%;视盘分割错误率与当前已知最好的算法相比由12.5%降低到了9.39%。结果表明:提出的眼底图像视盘自动定位与分割方法准确率高、实用性强,可以用于眼科疾病的计算机辅助诊断。