屈光参差性弱视的黄斑形态特征研究

目的评价屈光参差性弱视患者双眼黄斑厚度与形态特点。方法自身对照设计。在广西视光中心招募不伴斜视的中度和重度屈光参差性弱视患者85例,其中儿童组46例、成人组39例,同时招募与儿童组年龄匹配的已治愈的屈光参差性弱视患者35例为对照组;采集所有患者的屈光度、矫正视力、眼底频域光学相干断层扫描、眼轴长度等指标,定性评估黄斑中心凹光感受器内外节(photoreceptor inner and outer segment,IS/OS)形态,进行各指标在双眼间(弱视眼与对侧眼)的比较、组内相关与回归分析。结果儿童组除矫正视力、等效离焦度、眼轴长度3项指标在双眼间存在统计学差异外(均为P <0. 001),弱视眼黄斑中心凹1 mm直径区域厚度比对侧眼厚(7. 54±14. 42)μm(P=0. 001,95%可信区间为3. 26～11. 83μm)。对照组已治愈的弱视眼黄斑中心凹1 mm直径区域厚度比对侧眼厚(1. 94±4. 65)μm(P=0. 019,95%可信区间为0. 35～3. 54μm)。成人组双眼间黄斑中心凹1 mm直径区域厚度、黄斑中心凹最小厚度差异无统计学意义(均为P>0. 05)。儿童组弱视眼黄斑中心凹最小厚度与其等效离焦度呈负相关(r=-0. 338,P=0. 008)。成人组弱视眼黄斑中心凹1 mm直径区域厚度与其等效离焦度呈正相关(r=0. 447,P=0. 004)。黄斑中心凹IS/OS形态:已治愈弱视患者的IS/OS正常形态比例为80. 0%,明显高于儿童与成人弱视患者比例(58. 8%,χ2=9. 774,P=0. 002)。结论弱视眼黄斑中心凹1 mm直径区域厚度高于对侧眼,仅见于中重度弱视儿童及已治愈弱视儿童;成人弱视眼等效离焦度与其黄斑中心凹1 mm直径区域厚度呈正相关性;弱视眼黄斑中心凹形态呈欠发育特征。

屈光参差性弱视与屈光参差性近视双眼间高阶像差特征的对比研究

目的评估屈光参差性弱视与屈光参差性近视双眼间的高阶像差差异以及双眼间波前像差模式的特征。方法 85例非斜视性屈光参差患者被纳入本研究并被分成屈光参差性弱视组与屈光参差性近视组。其中屈光参差性弱视组按照最佳矫正视力情况再分为弱视眼和对侧眼亚组,屈光参差性近视组按照屈光度的高低再分为高度数眼和低度数眼亚组。所有患者均接受Wave Scan波前像差检测。配对t检验用于分析各组内双眼间的差异;Spearman相关分析和线性回归分析用于分析各亚组内变量间的相互关系。结果配对t检验与形态分析结果显示:(1)屈光参差性弱视组患者的弱视眼与对侧眼在等效离焦度、最佳矫正视力、总像差、总高阶像差以及三阶像差均方根值等指标上均存在统计学差异(均为P<0.05),形态上双眼间高阶像差呈非对称模式;(2)屈光参差性近视组患者中,仅发现等效离焦度、总像差均方根值两项指标在高度数眼与低度数眼之间存在统计学差异(均为P<0.05),形态上双眼间高阶像差有一定程度的相似性和对称性。Spearman相关分析显示:(1)屈光参差性弱视组弱视眼等效离焦度与其总像差均方根值(r=0.819,P=0.000)、三阶像差均方根值(r=-0.315,P=0.048)存在相关性,对侧眼等效离焦度与其总像差均方根值(r=0.876,P=0.000)亦存在相关性;弱视眼等效离焦度与其总像差均方根值的回归方程为y=2.275+1.066x(R2=0.668,F=76.447,P=0.000),对侧眼等效离焦度与其总像差均方根值的回归方程为y=1.462+1.214x(R2=0.721,F=98.170,P=0.000)。(2)屈光参差性近视组高度数眼等效离焦度与其总像差均方根值(r=0.852,P=0.000)、四阶像差均方根值(r=-0.313,P=0.037)存在相关性,低度数眼等效离焦度与其总像差均方根值(r=0.903,P=0.000)亦存在相关性;高度数眼等效离焦度与其总像差均方根值的回归方程为y=1.671+1.206x(R2=0.794,F=166.005,P=0.000),与四阶像差均方根值的回归方程为y=0.314-0.024x(R2=0.117,F=5.709,P=0.021),低度数眼等效离焦度与其总像差均方根值的回归方程为y=1.013+1.209x(R2=0.851,F=244.957,P=0.000)。结论双眼间高阶像差在屈光参差性弱视患者中呈非对称模式,在屈光参差性近视患者中则呈相似和对称模式。

不同程度远视屈光参差性弱视的波前像差特点

目的:评估不同程度远视屈光参差性弱视的波前像差特点。方法:远视屈光参差性弱视60例被纳入本研究,并被分成轻、中、重度三组,各组按矫正视力再分为弱视眼与对侧眼亚组。所有患者双眼均接受散瞳后波前像差检测。分析组内和组间双眼间波前像差差异。结果:轻、中、重度弱视各组内弱视眼与对侧眼的等效离焦度、矫正视力均有差异(P<0.01)。轻度弱视患者中,弱视眼仅四阶像差RMS值高于对侧眼(P<0.01);中、重度弱视组内弱视眼仅总像差RMS值高于对侧眼(均P<0.01)。三组间仅双眼间三阶像差RMS差值有差异(P<0.01),中度与轻度、重度组间均有差异(P<0.05)。结论:散瞳状态下,双眼间波前像差在轻度弱视表现为弱视眼四阶像差RMS值高于对侧眼,在中、重度弱视表现为弱视眼的总像差RMS值高于对侧眼;双眼间波前像差RMS差值在屈光参差性弱视表现为中度弱视的三阶像差RMS差值低于轻度、重度弱视。

波前像差在屈光参差性弱视光学质量评估中的应用

目的 探讨屈光参差性弱视双眼间的波前像差差异以及临床特点。方法 选取53例屈光参差性弱视患者,年龄9∽40岁,其中男31例,女22例,纳入本横断面研究。所有患者均接受Wave Scan波前像差检查,弱视眼与对侧眼之间的波前像差差异采用配对t检验;波前像差参数值、等效离焦度、最佳矫正视力,以及年龄之间的关系采用相关分析。然后将中度弱视患者按照年龄分为成年弱视组和儿童弱视组,分析这两组的临床特点。结果 经配对t检验显示,53例患者的弱视眼与对侧眼在最佳矫正视力、等效离焦度、总像差、总高阶像差、三叶草像差、三阶像差均方根值等指标上差异均有统计学意义（均为P〈0.05）。成年弱视组与儿童弱视组内均未发现年龄与高阶像差参数之间存在相关性。成年弱视组弱视眼与对侧眼之间在总像差（P=0.000）、三叶草像差（P=0.047）和三阶像差均方根值（P=0.032）上差异均有统计学意义（均为P〈0.05）;儿童弱视组弱视眼与对侧眼之间在总像差（P=0.000）、球差（P=0.008）和四阶像差均方根值（P=0.032）上差异均有统计学意义（均为P〈0.05）。两个年龄组内的相关回归分析显示,在成年弱视组,等效离焦度与总像差有相关性（P〈0.01）,最佳矫正视力与总像差、球差均有相关性（均为P〈0.05）;且等效离焦度与总像差的回归方程为y=3.343＋0.942x（F=40.830、P=0.000、R2=0.671）,最佳矫正视力与总像差的回归方程为y=0.321＋0.017x（F=5.058、P=0.036、R2=0.202）。在儿童弱视组,等效离焦度与总像差、总高阶像差均有相关性（均为P〈0.05）,最佳矫正视力与五阶像差均方根值存在相关性（P〈0.01）;等效离焦度与总像差的回归方程为y=1.529＋1.176x（F=17.090、P=0.001、R2=0.501）,最佳矫正视力与五阶像差均方根值的回归方程为y=0.006＋0.143x（F=10.851、P=0.004、R2=0.390）。结论 除最佳矫正视力、等效离焦度、总像差之外,屈光参差性弱视患者双眼间的高阶像差存在显著差异;对于中度弱视患者,双眼间高阶像差差异在成人与儿童表现不同。

已治愈与未治愈屈光参差性弱视患者双眼间的波前像差特点

目的探讨已治愈与未治愈屈光参差性弱视患者双眼间的波前像差特点。方法收集在广西视光中心就诊并自愿参加本研究的屈光参差患者共91例,根据病史和矫正视力将所有患者分成两组:对照组(已治愈的屈光参差性弱视) 31例、弱视组(未治愈的屈光参差性弱视) 60例。对照组按照等效离焦度的高低,将每例患者双眼的数据分别归入原弱视眼组和原对侧眼组;弱视组按照矫正视力是否正常,将每例患者双眼的数据分别列入弱视眼组和对侧眼组。弱视组患者按年龄分为成年弱视22例、未成年弱视38例。所有患者均接受i Design波前像差仪(美国AMO公司)检测,以均方根值(root mean square,RMS)形式表示总像差和各项高阶像差(RMS3～6)。配对t检验用于分析各组内双眼间的参数差异;独立样本t检验比较两组间的参数差异; Spearman相关分析和线性回归分析各亚组内变量间的相互关系。结果对照组原弱视眼等效离焦度高于原对侧眼,差异有统计学意义(P <0. 01);弱视组弱视眼等效离焦度、总像差RMS均高于对侧眼,差异均有统计学意义(均为P <0. 01);其余参数如总高阶像差、三阶像差、四阶像差、五阶像差、六阶像差RMS,在两组内双眼间的差异均无统计学意义(均为P> 0. 05)。散瞳状态下成年弱视组、未成年弱视组双眼间等效离焦度、总像差RMS差异均有统计学意义(均为P <0. 01),弱视眼均大于对侧眼。波前像差图像显示:对照组和弱视组双眼间总像差均呈非对称性、总高阶像差均呈相似性与对称性。将对照组、弱视组双眼间波前像差各参数差值进行组间比较,独立样本t检验结果提示:△等效离焦度以及△总像差RMS在两组之间的差异均有统计学意义(均为P <0. 01),弱视组均大于对照组;其余参数在两组间的差异均无统计学意义(均为P> 0. 05)。对照组、弱视组内双眼的等效离焦度均与其自身总像差RMS呈正相关;等效离焦度与其他波前像差参数之间无相关性。线性回归分析结果显示:对照组内原弱视眼的等效离焦度与总像差RMS的回归方程为Y=0. 16+0. 798X(R^2=0. 633,F=50. 031,P=0. 000),原对侧眼的等效离焦度与总像差RMS的回归方程为Y=1. 278+0. 611X(R^2=0. 522,F=31. 613,P=0. 000);弱视组内弱视眼的等效离焦度与总像差RMS的回归方程为Y=-1. 466+1. 149X(R^2=0. 825,F=272. 675,P=0. 000),对侧眼的等效离焦度与总像差RMS的回归方程为Y=1.101+0.832 X (R^2=0. 632,F=99. 561,P=0. 000)。结论散瞳状态下已治愈和未治愈的屈光参差性弱视患者等效离焦度和总像差形态在双眼间存在明显差异,但高阶像差在双眼间具有相似性和对称性。

基于时间散焦分析法的三维信息采集

为了测量被测物的距离信息,结合投影系统的三维信息采集方法,研究了一种基于时间散焦分析的三维信息采集方法。通过向被测物投影移动的条纹,分析照明模式在各点的散焦度,利用傅里叶变换解析被测物各点的距离信息。实验结果表明,该方法不需要考虑点匹配问题,能单独计算各点的位置信息,并且能测量较大的距离。

A Three-Dimensional Velocity-Map Imaging Setup Designed for Crossed Ion-Molecule Scattering Studies

In this study,we report the design and simulation of an electrostatic ion lens system consisting of 22 round metal plates.The opening of the extractor plate is covered withmetal mesh,which is for shielding the interaction region of the lens system from the high DC voltages applied to all other plates than the repeller and extractor plates.The Simion simulation shows that both velocity-mapping and time focusing can be achieved simultaneously when appropriate voltages are applied to each of the plates.This makes the ion lens system be able to focus large ionic volumes in all three dimensions,which is an essential requirement for crossed ion-molecule scattering studies.A three-dimensional ion velocity measurement system with multi-hit and potential multi-mass capability is built,which consists of a microchannel plate(MCP),a P47 phosphor screen,a CMOS camera,a fast photomultiplier tube(PMT),and a high-speed digitizer.The two velocity components perpendicular to the flight axis are measured by the CMOS camera,and the time-of-flight,from which the velocity component along the flight axis can be deduced,is measured by the PMT.A Labview program is written to combine the two measurements for building the full three-dimensional ion velocity in real time on a frame-by-frame basis.The multi-hit capability comes from the fact that multiple ions from the camera and PMT in the same frame can be correlated with each other based on their various intensities.We demonstrate this by using the photodissociation of CH31 at 304 nm.

Multifocal electroretinograms in the early stages of diabetic retinopathy

OBJECTIVE: To investigate the characteristics of multifocal electroretinograms (mf-ERG) of different phases in diabetic retinopathy (DR) and its clinical significance. METHODS: Multifocal electroretinograms in patients with DR (I - II stage) were tested with VERIS IV system. RESULTS: In I - II stage, the absolute values of N1, P1 and N2 response densities, and the N1-P1 and P1-N2 response densities were attenuated is a field of about 45 degrees in diameter. CONCLUSION: As a new objective and quantitative examination for spatial visual function, multifocal electroretinograms may be valuable in the diagnosis of diabetic retinopathy.

Multifocal electroretinograms in the early stages of diabetic retinopathy

To investigate the characteristics of multifocal electroretinograms (mf ERG) o f different phases in diabetic retinopathy (DR) and its clinical significance Methods Multifocal electroretinograms in patients with DR (Ⅰ-Ⅱ stage) were tested with VERIS Ⅳ system Results In Ⅰ-Ⅱ stage, the absolute values of N1, P1 and N2 response densities, and the N1 P1 and P1 N2 response densities were attenuated is a field of about 45 deg rees in diameter Conclusion As a new ABSTRACT and quantitative examination for spatial visual function, mul tifocal electroretinograms may be valuable in the diagnosis of diabetic retinopa thy

Pathological morphology alteration of the splanchnic vascular wall in portal hypertensive patients

To investigate the pathological morphology alteration of the splanchnic vascular wall in portal hypertensive patients Methods Splenic arteries, veins and gastric coronary veins from portal hypertensive pati ents (n=50) were removed during esophagogastric devascularization with splenecto my and were observed under optic and electron microscopes The expression of iN OS in the splenic artery wall was analysed with immunohistochemistry Results The internal elastic membrane and medial elastic fibers of the splenic artery wa ll were broken and degenerated Atrophy, apoptosis and phenotypic changes were seen in smooth muscle cells of splenic arteries Positive staining for iNOS was seen in the cytoplasm of smooth muscle cells and iNOS activity was elevated com pared with the non cirrhotic patients ( P 【0 01) In the splenic and gastri c coronary veins of cirrhotic patients, we found proliferative intima, extensive thrombi adhering to the venous wall, mimicked arteriosclerosis plaques accompan ied with hypertrophy of smooth muscle cells, and thickened muscle fibers of vein s with increase in extracelluar matrix Conclusion Portal hypertension may be complicated by splanchnic arterial and venous vasculo pathy There may be an interactive relationship among portal hypertension, spla nchnic hyperdynamic disturbances and splanchnic vasculopathy in the pathogenesis of portal hypertension

Fabrication technique of micro/nano-scale speckle patterns with focused ion beam

The fabrication technique of micro/nano-scale speckle patterns with focused ion beam (FIB) system is studied for digital image correlation (DIC) measurement under a scanning electron microscope (SEM).The speckle patterns are fabricated by directly etching the counterpart of the specimen to the black part of a template.Mean intensity gradient is used to evaluate the quality of these SEM images of speckle patterns fabricated based on different templates to select an optimum template.The pattern size depending on the displacement measurement sensitivity is adjusted by altering the magnification of FIB according to the relation curve of the etching size versus magnification.The influencing factors including etching time and ion beam current are discussed.Rigid body translation tests and rotation tests are carried out under SEM to verify the reliability of the fabricated speckle patterns.The calculated values are in good agreement with the imposed ones.