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1.
《蛇志》2019,(3)
目的比较人工晶状体(ICL V4)与中央孔型晶状体眼后房型人工晶体(ICL V4c)植入术治疗超高度近视患者术后的视觉质量。方法选取2017年4月~2019年6月我院收治的30例(60眼)超高度近视患者,随机分为对照组与观察组,每组各15例。对照组植入ICL V4,观察组植入ICL V4c。观察两组术后3个月裸眼视力矫正、矫正视力及并发症情况,比较两组术前与术后3个月明光、明视眩光、暗光、暗视眩光环境下的对比敏感度。结果两组术后3个月裸眼视力≥术前最佳矫正视力、最佳矫正视力提高≥2行百分比比较,差异无统计学意义(均P0.05)。两组术前与术后3个月在明光、明视眩光、暗光、暗视眩光环境下的对比敏感度比较,差异均无统计学意义(均P0.05)。两组术后3个月在明光、明视眩光、暗光、暗视眩光环境下的对比敏感度均明显高于术前(均P0.01)。对照组1眼眼压增高,观察组2眼眼压增高,两组术后均未出现自身晶状体浑浊。结论 ICL V4c和ICL V4治疗超高度近视患者术后的视觉质量无差异,但ICL V4c植入术无需再做房水引流通路,可减少手术操作与并发症。  相似文献   

2.
探讨近视眼LASIK术后眼波阵面像差高阶像差各项的变化。方法:采用NIDEK OPD-Scan ARK-1000型波前像差扫描系统对LASIK治疗近视的62只眼在术前术后眼的波前像差进行了评估。在术前、术后10天、术后一个月分别测量眼的波阵面像差。比较6mm瞳孔下高阶像差各项的变化。结果:在全部接受检查的病例中,总的高阶像差(RMSh)均有所增加。从Zernik各项绝对值来看,球差C12变化最大。术后10天比术前增加6.7742倍(P=0.0001)。其次是彗差C7 C8(X轴、Y轴上的彗差),分别增加了4.883倍(P=0.0001)、3.7523倍(P=0.0001)。结论:LASIK术后眼的总的高阶像差均方根值(RMSh)明显增加,尤其是球差和彗差;但在恢复过程中高阶像差有下降的趋势。用像差仪来指导和评估LASIK等屈光手术可以更全面、更准确。  相似文献   

3.
目的:波前像差引导的准分子激光角膜消融是屈光手术的新方法,研究人眼波前像差的测量原理、方法、表示、人眼波前像差准分子激光矫正的原理,以此理论用于准分子激光人眼像差矫正系统。方法:采用理论研究、计算机模拟、实验室实验等手段。分析人眼像差的概念和产生的原因,用数学的Zern ike多项式来表示像差,理论上定量分析Zern ike多项式表示的波前像差与角膜切削深度的关系,研究准分子激光切削角膜的机理,研究准分子激光进行矫正人眼像差的原理框图。结果:通过计算机模拟和实验室实验,用准分子激光矫正低阶和高阶像差是可行的。结论:用波前像差来引导屈光手术,使人眼的视力能够达到20/10上,并能避免当前PRK、LASIK屈光手术前后像差增大而引起的对视觉质量的影响。  相似文献   

4.
目的:观察皮质类固醇激素冲击疗法对准分子激光原位角膜磨镶术(excimer laser in situ keratomileusis, LASIK)治疗近视术后发生屈光回退的治疗效果, 探讨此方法在临床应用的可能性.方法:对LASIK术后发生屈光回退的近视眼患者24例(48眼)采用皮质类固醇激素冲击疗法:每天9次0.1 %氟美童滴眼液点眼, 3周后改为每天4次逐周递减再治疗4周.治疗后进行了6个月的临床观察, 评价患者的视力和屈光度改变.结果:LASIK术后出现屈光回退的病例经激素治疗后视力得到改善, 屈光状态得到改变, 治疗后3周与7周的效果差异不显著.药物治疗中有激素性高眼压和其他激素副作用产生, 经降眼压治疗后未对视功能产生明显影响.结论:皮质类固醇激素冲击疗法治疗LASIK术后屈光回退并发症安全有效, 是再次LASIK手术治疗屈光回退的补充.  相似文献   

5.
目的:评价、研究玻璃体切割术治疗严重角巩膜裂伤的临床疗效。方法:对我院2011-12/2013-12住院的39例39眼角巩膜裂伤(本组病例一期伤口均≥1.0cm)患者行玻璃体切割术治疗,术中根据视网膜情况酌情辅以视网膜光凝、惰性气体充填、硅油充填。结果:手术后随访3~12个月,随访中行视力、最佳矫正视力、眼压、眼底及B超检查,部分屈光间质透明度较好的患眼进行了OCT和眼底照相检查。患者中39例38眼眼球结构维持良好,视网膜复位良好。术后视力不同程度提高29例29眼,其中0.1者由术前0眼增加到术后的13眼;术后视力无变化4例4眼,其中3例3眼术前术后视力无光感。结论:玻璃体切割术是治疗严重角巩膜裂伤的有效方法。  相似文献   

6.
目的:探究左旋多巴联合综合疗法治疗屈光不正性弱视患儿的临床效果。方法:选取2013年4月至2016年3月在我院接受治疗的屈光不正性弱视青少年103例(180眼),随机分为对照组52例(90眼)和观察组51例(90眼)。对照组患儿给予常规的综合治疗,观察组在对照组之上给予左旋多巴治疗。治疗6个月后,观察比较两组患儿的治疗有效率、图形视觉诱发电位(P-VEP)、视觉对比敏感度和视功能等以及不良反应的发生情况。结果:观察组的视力治疗有效率为90.00%,显著高于对照组(68.89%),差异具有统计学意义(P0.05)。治疗6个月后,两组的振幅出现明显的升高,且观察组显著高于对照组(P0.05);两组的潜伏期发生明显降低,且观察组的显著低于对照组(P0.05)。观察组患儿的100%、25%、10%及5%空间频率视觉对比敏感度均显著低于对照组(P0.05)。观察组患儿的矫正辐辏范围、矫正分开范围显著高于对照组,矫正近立体锐度显著低于对照组(P0.05)。治疗期间,两组不良反应发生情况比较差异无统计学意义(P0.05)。结论:左旋多巴联合综合疗法可有效改善屈光不正患儿的视觉中枢神经元功能,明显提高视力水平及视觉敏感度。  相似文献   

7.
影响人眼视觉质量的光学因素   总被引:2,自引:0,他引:2  
人眼作为一种光学器官,存在着一些光学缺陷,从物理学的角度分析了小瞳孔的衍射效应、眼球光学系统的像差、瞳孔尺寸、照明度和光学散射等对人眼视觉质量的影响。重点分析了由眼球的屈光介质引入的光学像差对人眼视觉质量的影响。  相似文献   

8.
徐华斌  吴中林  刘传先  邢冰  陈林 《激光生物学报》2007,16(5):659-662,F0003
人眼离焦和散光两个缺陷可以通过佩戴框架眼镜、角膜接触镜、激光屈光手术得到矫正。但是,即使矫正后的眼睛屈光处于最佳状态,但仍不能获得最佳视觉敏锐度。这是因为人眼存在着光学像差。从人眼像差的测量方法和数值表示法来进行分析,并引入Zern ike多项式来表示波前像差,为用准分子激光进行眼球像差矫正提供理论依据。  相似文献   

9.
目的:利用血氧水平依赖性功能性磁共振成像(BOLD-fMRI)技术及非金属MRI专用眼镜,分析探索屈光不正对儿童大脑皮层视觉功能区神经元活动的影响。方法:以1.5T磁共振成像系统采集8例屈光不正眼儿童屈光矫正前后枕叶视皮层兴趣区BOLD—fMRI数据,及8例正常眼凸透镜离焦前后枕叶视皮层兴趣区BOLD—fMRI数据,进行对比分析,比较屈光不正眼及其矫正后、正常眼及其离焦后皮层视觉功能区神经元活动的不同,分析其改变特点及原因。结果:屈光不正眼儿童矫正屈光后皮层视觉功能区神经元活动范围明显增加(P〈0.05);正常眼离焦后皮层视觉功能区神经元活动范围明显减小(P〈0.05)。结论:屈光不正会明显降低儿童皮层视觉功能区的神经元活动。屈光不正患儿应尽早配镜矫正,以免影响视觉皮层功能发育。  相似文献   

10.
目的:玻璃体切割联合硅油注入治疗增殖型糖尿病视网膜病变的术后护理的临床效应。方法:对88例增殖型糖尿病视网膜病变患者采用玻璃体切割联合硅油注入术后的护理,针对糖尿病病人的特点及硅油注入的特殊要求提出术后严密观察眼部情况,控制血糖、保持特殊体位、预防眼压升高等并发症。结果:手术后患者视力均有不同程度提高,对玻璃体切割联合硅油注入术使许多糖尿病病人加强术后护理,有助于恢复患者的有用视力、提高手术效果的临床效应,提高生存质量。结论:针对糖尿病病人的特点,在围手术期做好周密的护理,对于提高手术疗效是十分重要的。  相似文献   

11.
Photorefractive keratectomy (PRK) and laser assisted in situ keratomileusis (LASIK), using an excimer laser, are the currently popular techniques of correcting refractive errors. Since these techniques work by selective ablation of corneal stroma, the tissue healing response plays a great role in the ultimate outcome of surgery. Also, various methods of wound healing modulation can be used to achieve better results. While these procedures do lead to a decrease in dioptric power and increase in unaided visual acuity, higher visual functions like contrast sensitivity can sometimes be compromised after the surgery.  相似文献   

12.
The purpose was to determine the optimum negative spherical aberration induction required to improve near and intermediate visual acuity (VA) of presbyopic eyes. A total of 174 normal and diabetic (no retinopathy) presbyopic eyes (age ≥ 40 years) were measured with visual adaptive optics simulator (Voptica, Spain). First, baseline uncorrected VA and aberrations were measured. VA at 40 cm (near), 80 cm (intermediate) and distance was measured. Then, a negative spherical aberration (SA) was added to baseline ocular SA, and VA at all targets was reassessed after correction of distance refractive error. Clinically, baseline SA and root mean square of higher order aberrations were similar between the normal and diabetic presbyopic eyes. Baseline VA of the diabetic eyes at near and intermediate was better than the same of normal eyes (P = 0.001). After SA change, VA at near and intermediate of both normal and diabetic presbyopic eyes improved. However, fewer diabetic eyes needed higher SA change than normal eyes (P = 0.03). The corresponding trends with change in VA at near and intermediate were also similar between the normal and diabetic eyes. Patient‐specific modulation of ocular SA to improve near and intermediate VA in a large cohort of eyes was successful in improving VA, sometimes even distance VA.   相似文献   

13.
There are several methods for presbyopia treatment. Refractive lens exchange (RLE) followed by multifocal intraocular lens (MFIOL) implantation enables high rate of spectacle independence but have some visual disturbances. Laser in Situ Keratomileusis (LASIK) monovision gives patient ability to have good distant vision with dominant eye and good near vision with nondominant eye. In this prospective randomized study we wanted to compare clinical outcomes in patients who underwent either of the mentioned procedures. The first group included 50 patients (N = 100 eyes) who underwent RLE with MFIOL implantation and the second group included 50 patients (N = 100 eyes) who underwent LASIK monovision as presbyopia treatment. Uncorrected distant, near and intermediate visual acuity, patient's subjective satisfaction and visual disturbances were measured. Follow up was 6 months. Patients in RLE group had better near uncorrected visual acuity (UCVA) and patients in LASIK monovision group had better distant and intermediate vision. Patients in RLE group reported visual disturbances (halo, glare). Patients satisfaction and spectacle independence was high in both groups. Refractive lens exchange with multifocal intraocular lens implantation and LASIK monovision are effective methods for presbyopia treatment. LASIK monovision with -0.50D - 1.25D of residual dioptry at nondominant eye in patients under 50 years enables good vision at all distances without affecting stereovision. Patient selection and preoperative counseling are key to success.  相似文献   

14.
目的:探讨连续q全遮盖法治疗双眼屈光参差性弱视的有效性与安全性。方法:选择2014年2月到2016年9月在我院诊治的126例双眼屈光参差性弱视患儿作为研究对象,根据治疗方法的不同分为阿托品组60例与遮盖组66例,遮盖组采用连续全遮盖法治疗,阿托品组给予阿托品治疗,两组都治疗观察3个月。比较两组治疗期间不良反应的发生情况、治疗后的总有效率、最佳矫正视力、电位潜伏期、波幅。结果:两组治疗期间都无严重不良反应发生。治疗后,遮盖组与阿托品组的总有效率分别为98.5%和88.3%,遮盖组的总有效率明显高于阿托品组(P0.05)。两组治疗后的最佳矫正视力都高于治疗前,且遮盖组治疗后的最佳矫正视力也明显高于阿托品组(P0.05)。两组治疗后的电位潜伏期都较治疗前明显缩短,而波幅明显增强(P0.05),且遮盖组治疗后的潜伏期明显短于阿托品组,而波幅显著强于阿托品组(P0.05)。结论:连续全遮盖法治疗双眼屈光参差性弱视具有很好的安全性,能提高患儿的治疗效果,改善视力,促进神经元的兴奋性。  相似文献   

15.
The optical performance of the human cornea under intraocular pressure (IOP) is the result of complex material properties and their interactions. The measurement of the numerous material parameters that define this material behavior may be key in the refinement of patient-specific models. The goal of this study was to investigate the relative contribution of these parameters to the biomechanical and optical responses of human cornea predicted by a widely accepted anisotropic hyperelastic finite element model, with regional variations in the alignment of fibers. Design of experiments methods were used to quantify the relative importance of material properties including matrix stiffness, fiber stiffness, fiber nonlinearity and fiber dispersion under physiological IOP. Our sensitivity results showed that corneal apical displacement was influenced nearly evenly by matrix stiffness, fiber stiffness and nonlinearity. However, the variations in corneal optical aberrations (refractive power and spherical aberration) were primarily dependent on the value of the matrix stiffness. The optical aberrations predicted by variations in this material parameter were sufficiently large to predict clinically important changes in retinal image quality. Therefore, well-characterized individual variations in matrix stiffness could be critical in cornea modeling in order to reliably predict optical behavior under different IOPs or after corneal surgery.  相似文献   

16.

Purpose

To compare the visual performance of multifocal intraocular lenses (IOLs) and monofocal IOLs made of the same material.

Methods

The subjects included patients implanted with either Tecnis® monofocal IOLs (ZA9003 or ZCB00) or Tecnis® multifocal IOLs (ZMA00 or ZMB00) bilaterally. We conducted a retrospective study comparing the two types of IOLs. The multifocal group included 46 patients who were implanted with Tecnis® multifocal IOLs bilaterally. The monofocal group was an age- and sex-matched control group, and included 85 patients who were implanted with Tecnis® monofocal IOLs bilaterally. Lens opacity grading, the radius of corneal curvature, corneal astigmatism, axial length and the refractive status were measured preoperatively. Pupil size, ocular aberrometry, distance, intermediate and near visual acuity, contrast sensitivity with and without glare and the responses to a quality-of-vision questionnaire were evaluated pre- and postoperatively.

Results

The uncorrected near visual acuity was significantly better in the multifocal group, whereas both the corrected intermediate and near visual acuity were better in the monofocal group. Contrast sensitivity (with and without glare) was significantly better in the monofocal group. The rate of spectacle dependency was significantly lower in the multifocal group. There were no significant differences between the two groups regarding most items of the postoperative quality-of-vision questionnaire (VFQ-25), with the exception that the patients in the monofocal group reported fewer problems with nighttime driving.

Conclusions

The multifocal IOLs used in this study reduced spectacle dependency more so than monofocal IOLs and did not compromise the subjective visual function, with the exception of nighttime driving.  相似文献   

17.
A tertiary care center-based prospective case–control study was undertaken to evaluate the association of contrast sensitivity with LogMAR visual acuity and glycosylated hemoglobin (HbA1c) in 205 cases of non-insulin dependent diabetes mellitus and 115 controls. LogMAR visual acuity and contrast sensitivity were scored using ETDRS and Pelli-Robson charts, respectively. Bivariate correlation between contrast sensitivity and LogMAR visual acuity showed significant inverse correlation in cases without retinopathy (r = −0.466) and with non-proliferative retinopathy (r = −0.307). In a multivariate model, on applying linear regression analysis, LogMAR visual acuity (p < 0.001) and HbA1c (p = 0.002) had significant association with contrast sensitivity. Significant difference in contrast sensitivity was not observed between cases without diabetic retinopathy and with non-proliferative diabetic retinopathy, implying no association with retinal microvascular changes. Contrast sensitivity dysfunction observed in diabetes mellitus results from changes in retinal function secondary to alteration in carbohydrate metabolism depicted in glycosylated hemoglobin.  相似文献   

18.
The purpose of this study is to develop a 3D patient-specific finite element model (FEM) of the cornea and sclera to compare predicted and in vivo refractive outcomes and to estimate the corneal elastic property changes associated with each procedure. Both eyes of a patient who underwent laser-assisted in situ keratomileusis (LASIK) for myopic astigmatism were modeled. Pre- and postoperative Scheimpflug anterior and posterior corneal elevation maps were imported into a 3D corneo-scleral FEM with an unrestrained limbus. Preoperative corneal hyperelastic properties were chosen to account for meridional anisotropy. Inverse FEM was used to determine the undeformed corneal state that produced <0.1% error in anterior elevation between simulated and in vivo preoperative geometries. Case-specific 3D aspheric ablation profiles were simulated, and corneal topography and spherical aberration were compared at clinical intraocular pressure. The magnitude of elastic weakening of the residual corneal bed required to maximize the agreement with clinical axial power was calculated and compared with the changes in ocular response analyzer (ORA) measurements. The models produced curvature maps and spherical aberrations equivalent to in vivo measurements. For the preoperative property values used in this study, predicted elastic weakening with LASIK was as high as 55% for a radially uniform model of residual corneal weakening and 65% at the point of maximum ablation in a spatially varying model of weakening. Reductions in ORA variables were also observed. A patient-specific FEM of corneal refractive surgery is presented, which allows the estimation of surgically induced changes in corneal elastic properties. Significant elastic weakening after LASIK was required to replicate clinical topographic outcomes in this two-eye pilot study.  相似文献   

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