高度近视与近视视网膜脱离眼周边视网膜光敏感度的状态分布

目的:观察高度近视与近视视网膜脱离眼(RD)的视网膜周边部视功能状态分布特点—90°视网膜光敏感度,为预防性治疗视网膜脱离提供依据。方法:采用Octopus101中的周边低视力程序(LVP),对高度近视360例的视网膜周边部视功能状态-90°视网膜平均光敏感度(MS)、四象限光敏感度、四象限视野绝对暗点、平均视野绝对暗点进行定性定量检测,并分别与高度近视性视网膜脱离对侧眼161例、高度近视性视网膜脱离眼118例、正常眼108例、中低度近视视网膜脱离眼41例及其对侧眼54例进行对比分析,共计842例。结果:高度近视眼平均光敏感度(21.3±5.4)dB,视力0.56±0.37;高度近视视网膜脱离对侧眼(20.4±5.2)dB,视力0.55±0.40;正常对照眼(27.6±3.6)dB,视力1.00±0.00;高度近视视网膜脱离眼(14.1±5.7)dB,视力0.19±0.26;中低度近视视网膜脱离眼(15.6±5.7)dB,视力0.27±0.32;中低度近视视网膜脱离对侧眼(23.3±4.9)dB,视力0.87±0.27。视力和平均光敏感度在高近组与高度近视视网膜脱离对侧眼,在高度近视视网膜脱离与中低度近视视网膜脱离的差异无统计学意义。高度近视眼视野平均绝对暗点(9.3±8.7)个,高度近视视网膜脱离对侧眼(10.5±8.2)个,正常对照眼(4.6±4.5)个,高度近视视网膜脱离眼(19.8±11.0)个,中低度近视视网膜脱离眼(17.5±12.0)个,中低度近视视网膜脱离对侧眼(7.2±6.0)个。平均视野绝对暗点在高度近视组与高度近视视网膜脱离对侧眼和中低度近视视网膜脱离对侧眼,在高度近视视网膜脱离与中低度近视视网膜脱离的差异无统计学意义。结论:高度近视眼已经存在明显周边部视网膜光敏感度的严重损害,与视网膜脱离高危眼在发生视网膜脱离之前相似;高度近视眼和中低度近视视网膜脱离手术成功复位后,周边部视网膜光敏感度仍会降低,且中心视力仍呈不可逆降低;与正常人群、中低度近视有着明显的功能和结构的差异。     

健康照明与儿童近视防控的研究进展

近视在我国发病率较高,是影响儿童视觉健康的重要因素。现有的研究表明,过长的屏幕使用时间和过少的户外活动是儿童近视的重要诱因,这些危险因素都与光照参数,如光照强度、时常、频率、光谱有关。并且,不当的夜间照明也会对儿童的昼夜节律、睡眠产生影响并导致近视。现对屏幕时间、户外活动、光照属性以及昼夜节律的临床研究以及流行病学资料进行综述,为儿童近视预防提供一些建议与指导。     

高度近视的视觉诱发电位和视网膜电图观察

对152眼高度近视进行了P－VEP分析，对143眼高度近视进行了F－ERG分析。结果表明：随屈光度的加深，P100波的振幅下降，潜伏期延长，a、b波振幅下降。这从电生理角度进一步表明高度近观随着屈光度加深，眼底受损程度亦加重。定期对高度近视眼检测P－VEP和F－ERG可为病情的判断、预后的估计和临床治疗提供一定的客观依据。     

高度近视眼的视觉电生理研究

目的 :了解不同程度度高度近视眼的视觉电生理改变。方法 :将 12 4只高度近视眼按不同的屈光度分成 3组 (简称高近组 ) ,对此 3组以及 110只正常眼对照组采用美国LKCUTAS E30 0 0型视觉电生理仪检查FERG及PVEP。结果 :高近Ⅰ、Ⅱ、Ⅲ组ERG闪烁光的峰时值分别为 (2 8 74± 3 17)ms、(32 30± 10 71)ms、(31 0 3± 2 4 6 )ms ,均较对照组峰时值 (2 8 30± 2 16 )ms延长 ,差异有显著性 (P <0 0 5 ) ;高近Ⅰ、Ⅱ、Ⅲ组ERG闪烁光的振幅分别为 (6 4 13± 2 2 96 )mv、(4 8 6 0± 2 4 30 )mv、(39 75± 10 10 )mv ,均较对照组振幅 (83 70± 33 18)mv降低 ,差异有显著性 (P <0 0 5 )。高近Ⅰ组ERG最大反应a、b波振幅为 (194 4 6± 6 6 6 5 )mv、(4 15 4 0± 130 4 0 )mv ,高于高近Ⅱ组 (14 7 19± 6 9 99)mv、(32 7 0 0± 97 5 4 )mv ,差异有非常显著性 (P <0 0 1) ,高近Ⅱ组ERG最大反应a、b波振幅高于高近Ⅲ组 (12 0 80± 32 73)mv、(30 2 5 0± 4 3 89)mv ,差异有显著性 (P<0 0 5 )。高近 3个组a波振幅的下降程度较b波明显 ,b/a比值 >2 0。高近Ⅱ组的VEP振幅较对照组下降 ,有非常显著性差异 (P <0 0 1)。高近 3个组的眼轴较对照组长 ,有非常显著性差异 (P <0 0 1)。高近Ⅰ组的角膜曲率     

视网膜脱离90例94眼临床分析

目的:探讨视网膜脱离的临床特点和手术疗效。方法:回顾分析90例94眼各种类型视网膜脱离的临床特点、相关因素与疗效的关系及并发症。结果:治愈85眼占91%。复发6眼占6%。失败3眼占3%。术后视力提高者75眼(80%)。16眼视力无进步(17%)。视力下降3眼(3%)。本组19眼是正视眼发病率为20%。对侧眼视网膜脱离9眼,视网膜有各种变性41眼,有干性裂孔9眼。术后主要并发症是早期高眼压共18眼(60%)。结论:术前查找裂孔是手术成败的关键。视网膜脱离范围大或有黄斑裂孔术后视网膜脱离复发率高。近视眼是发生视网膜脱离的高危因素,眼或头部外伤是正视眼发病的危险因素。     

早产儿健康眼出生时视网膜电图特点

目的 了解早产儿出生时视网膜功能发育程度，比较早产儿和足月 产婴儿出生时视 网膜功能发育的异同。 方法 健康无眼病的早产儿10例10只眼和足月产 婴儿20例20只眼，随 机选取1只眼在出生后1周内进行闪光视网膜电图（FERG）检测，记录视杆细胞反应、视锥细 胞反应、最大混合反应，振荡电位（OPs）及30 Hz闪烁光反应。 结果 与足月产 婴儿比较，早产儿出生时视杆细胞反应潜伏期明显延长 (t=3.216，P=0.003)，振幅明显降低(t=6.050，P=0.000），差异有统计学意义；最大反应a、b波潜伏期差异无 统计学意义(t=0.465，P=0.650；t=1.068，P=0.295)，而振幅降低(t=6.584，P=0.000；t=6.649，P=0.000)差异有统计学意义。两组婴儿视锥细胞反应a、b波潜伏期 差异无统计学意义(t=0.077，P=0.939；t=0.935，P=0.358)，早产儿组振幅明显降 低(t=3.417，P=0.002；t=6.310，P=0.000)， 差异有统计学意义；两组间30 Hz闪烁光峰值潜伏期差异无统计学意义(t=0.968，P=0.341），早产儿组振幅明显降低（t=3.745，P=0.001），其差异有统计学意义。 两组间最大混合反应的b／a波振幅比值差异无统计学意义(t=0.215，P=0.831)。 结论 出生时早产儿视网膜的发育程度低于足月产婴儿。     

视觉健康管理背景下眼视光教育的探索与实践

世界卫生组织及我国"健康中国"战略都将视觉健康管理提升到前所未有的高度,多方位、全周期保障民众视觉健康,增强人们视觉保健的意识是我国实现健康中国的战略重点.而人才培养是行业发展的命脉与基石,因此眼视光人才教育的探索与建设又是重中之重.本文以天津医科大学眼视光专业为例,就当今社会视觉健康管理的背景下,如何切实有效地开展眼...     

中高度近视选择LASEK术前的预防性视网膜光凝的疗效观察

目的:评价中、高度近视选择LASEK术前的预防性视网膜光凝的疗效。方法:对中、高度近视患者279例551眼术前美多丽滴眼液充分散瞳后,用90D裂隙灯前置镜或三面镜详细检查眼底,明确有视网膜变性(格子样变性、蜗牛样变性、囊样变性等)或(伴)有干性裂孔共18例26眼,行倍频Nd:YAG532nm激光治疗并选择LASEK手术矫正近视。结果:对18例26眼行预防性倍频Nd:YAG532nm激光光凝术后周边视网膜变性及干性裂孔区封闭良好,色素斑形成明显。LASEK术后6～18mo随访,没有发生孔源性视网膜脱离。结论:对明确有视网膜变性或(伴)干性裂孔预防性行倍频Nd:YAG532nm激光光凝术及选择LASEK术矫正近视是预防准分子激光术后出现孔源性视网膜脱离的重要措施。     

近视的周边视网膜变性的预防性激光治疗

目的：评价近视的周边视网膜变性和／或裂孔进行预防性光凝的疗效。方法：周边视网膜变性和／或裂孔101例138眼，合并局限性浅脱离8眼，予以预防性激光治疗，随访观察其疗效。结果：氪激光对预防近视周边视网膜变性有显著疗效。随访2年，无1例发生视网膜脱离，且中心矫正视力同术前，结论：对近视的周边视网膜变性和／或裂孔应尽早进行 视网膜光凝治疗，不失为一种安全有效的方法。     

光线昼夜节律紊乱与近视的关系

寻找近视危险因素并及早干预是现代近视防控工作的重点。大量人群流行病学调查及实验室研究提示光线昼夜节律紊乱可能干扰眼球的正常发育,导致近视发生发展。笔者通过对近几年夜间照明、长时间日照所致的光周期紊乱与近视关系的相关研究作一概述,并就光昼夜节律紊乱与近视发生发展的机制进行简要探讨。     

Light intensity modulates corneal power and refraction in the chick eye exposed to continuous light

Continuous exposure of chicks to light was shown to result in severe hyperopia, accompanied by anterior segment changes, such as severe corneal flattening. Since rearing chicks in complete darkness results only in mild hyperopia and minor changes in corneal curvature, we hypothesized that light intensity may play a role in the development of refractive changes under continuous light illumination. To test this hypothesis, we examined the effects of rearing chicks under various continuous light intensities. More specifically, we investigated the refractive parameters of the chicks’ eyes, and avoided light cycling effects on ocular development. To this end, thirty-eight chicks were reared under 24-h incandescent illumination, at three different light intensities: 10,000 lux (n = 13), 500 lux (n = 12), and 50 lux (n = 13). Their eyes underwent repeated retinoscopy, keratometry, and ultrasound biometry, as well as caliper measurements of enucleated eyes. Both refraction and corneal refractive power were found to be correlated with light intensity. On day 90 after hatching, exposure to light intensities of 10 000, 500, and 50 lux resulted in hyperopia of +11.97 ± 3.7 (mean ± SD) +7.9 ± 4.08 and +0.63 ± 3.61 diopters (D), respectively. Under those intensities, corneal refractive power was 46.10 ± 3.62, 49.72 ± 4.16, and 56.88 ± 4.92 D, respectively. Axial length did not differ significantly among the groups. The vitreous chamber was significantly deeper in the high than in the low-intensity groups. Thus, during the early life of chicks exposed to continuous lighting, light intensity affects the vitreous chamber depth as well as the anterior segment parameters, most notably the cornea. The higher the intensity, the more severe was the corneal flattening observed and the hyperopia that developed, whereas continuous illumination at low intensities resulted in emmetropia. Thus, light intensity is an important factor that should be taken into account when studying refractive development.     

The electroretinogram, standing potential, and light peak of the perfused cat eye during acid-base changes

DC recordings of light-evoked responses were made in the isolated, arterially perfused cat eye during four acid-base changes designed to alter intracellular pH (pHi) without appreciably altering extracellular pH (pH0). Two acid-base changes were designed to decrease pHi: substitution of high pCO2, high [HCO3-] perfusate for control perfusate and injection of NaHCO3 solution (pH 7.4) into the control perfusate. The initial effects of these two changes were similar: standing potential decreased, the b-wave amplitude decreased, and the c-wave amplitude increased. Subsequent effects, which included rebounds, were complex. The two other acid-base changes were designed to increase pHi: substitution of low pCO2, low [HCO3-] perfusate for the control perfusate and injection of NH4Cl solution into the control perfusate. The initial effects of these two changes were similar; the effects were opposite to those described above for acid-base changes (i) and (ii). The effects of all four acid-base changes were reversible. From these and previously published findings on the effects of pH0, we conclude that during acid-base changes, the initial change in the standing potential varies directly with pHi/pH0, the initial change in b-wave amplitude varies directly with pHi, and the initial change in c-wave amplitude varies inversely with pHi. We also studied the effects of the four acid-base changes on the light peak, a slow voltage response to light generated by the retinal pigment epithelium. Under acid-base changes (i), (ii), and (iii) the light peak was severely depressed. Injection of 2 mM NH4Cl, acid-base change (iv), had little effect on the light peak; however, injection of 5-10 mM NH4Cl did depress the light peak. These results may be interpreted in several ways, for example, the light peak may be sensitive to changes in [HCO-3]0 or to pHi. In any case, we conclude that pH0 is a relatively minor factor influencing the amplitude of the light peak.     

Effects of light and dark adaptation of rods on specific-hue threshold

Specific-hue threshold as a function of absolute rod threshold was measured with long-, middle-, and short-wavelength monochromatic test lights presented 17 deg extrafoveally. The measurements were obtained both during the rod phase of long-term dark adaptation and under conditions where the rod receptor system was gradually light adapted from a dark-adapted state by a scotopic background field of increasing retinal illumination. The results show that change in specific-hue threshold with change in absolute rod threshold is not, in general, identical for light and dark adaptation of the rod receptor system. Thus, in the long- and middle-wavelength test regions, the specific-hue threshold could be obtained at higher intensities under the light- as compared to the dark-adaptation condition when absolute rod thresholds were the same. Just the opposite was found for the short-wavelength tests. It is concluded that change in specific-hue threshold with light and dark adaptation of the rod receptor system is not, in general, controlled by the same mechanism.     

Outcome of vision screening of eye health workers at a tertiary eye hospital in north-western Nigeria

目标:评估尼日利亚三级公共眼科医院中眼部保健工作者的眼部健康状况.方法:基于医院的横断面研究,这项研究中使用自填问卷收集参与研究的工作人员基本的人口统计学信息.每一位受试者都进行了眼部综合检查,包括裸眼或矫正视力、详细的眼前节和眼后节检查,以及使用Goldman眼压计测量眼压.有青光眼视神经病变征象的,或周围前房深度小于角膜厚度25%的受试者接受了房角镜检查.可能患有青光眼的人进行了中央视野分析(24-2,SITA Standard).视力使用WHO视力受损分类标准镜像分类.结果:共有275例保健工作人员进行了筛查,其中176(64%)为非临床工作人员.166人(60.4%)受调查者是男性,13.1%有眼部疾病家族史.大部分受访者(86.2%)视力正常(6/18-6/6).然而1.5%的有严重的视力障碍.女性有严重视力障碍的比例更大(3.7%vs 0%,P=0.018).然而,我们观察到临床工作人员和非临床工作人员的视力情况无统计学差异(P=0.41).右眼和左眼的平均杯盘比分别为0.42、0.45,两者之间的差异没有显著性(t=-0.882,P=0.37).右眼和左眼的眼压平均为14.1、14.0 mmHg.右眼眼压和右眼杯盘比之间、左眼眼压和左眼杯盘比之间存在弱相关.老花和屈光不正是受筛查人群中最常见的眼部疾病.有14位受访者(5.1%)患原发性开角型青光眼.而47人疑患有青光眼.结论:未矫正的屈光不正、白内障和青光眼是眼部保健工作者中最常见的导致视力障碍的眼部疾病.这项研究强调了定期进行工作人员体检以保证及时的诊断和治疗对患病人员的必要性.     

窄谱滤光片屏蔽460～480nm蓝光后正常成人视功能的变化

目的 观察屏蔽460～480 nm蓝光后正常成年人视功能的变化.方法 自身对照研究.选取24例正常成年人,分别比较其在正常未干预情况下、配戴屏蔽460～480 nm蓝光滤光片(窄谱滤光片)后和配戴普通市售黄色镜片(屏蔽部分380～550 nm可见光)后,在2种照度环境中(1 000 lx、40 lx)色觉的错误总分值(TES)和10个分色区错误分值(PES),并比较明环境、暗环境、暗眩光环境中5个空间频率(1.5、3.0、6.0、12.0、18.0 c/d)对比敏感度的变化,采用配对秩和检验对各组数值进行统计学分析.结果 2种照度环境下,配戴窄谱滤光片或黄色镜片后FM100-Hue色棋检查的TES和多个分区PES均高于未干预状态(P＜0.017).配戴窄谱滤光片状态和配戴黄色镜片状态相比,在2种照度环境下,黄色镜片状态TES和多个分区PES均高于窄谱滤光片状态(P＜0.017).明环境和暗环境中,3种状态下在5个空间频率对比敏感度的差异无统计学意义,暗眩光环境中,配戴窄谱滤光片状态在6.0 c/d空间频率对比敏感度值高于未干预状态(P＜0.017).结论 通过光学薄膜技术将460～.480 nm波长光特异性屏蔽后,正常成年人的色觉辨别力有一定程度的下降,但和普通黄色镜片相比影响程度较轻.特异性屏蔽460～480 nm蓝光后,成年人在中频的对比敏感度显著提高,这种改善作用优于普通黄色镜片.     

Retinal-image mediated ocular growth as a mechanism for juvenile onset myopia and for emmetropization

The very common ocular clinical ocular condition in children juvenile onset myopia results from axial elongation of the eye. In humans, some studies have found an association of myopia with greater levels of nearpoint activity and with differences in accommodation and convergence function. This paper reviews a variety of laboratory and clinical studies which are consistent with the hypothesis that retinal image defocus is biochemically transformed into an axial elongation expressed through increased posterior segment growth, and thus myopia. This paper also reviews theories of emmetropization, and classifies them as correlational, feedback, and combination. Evidence is presented to suggest that a combination theory, which combines both correlation of the ocular dioptric components and some feedback mechanism for growth of the eye, is the most correct. Current laboratory research suggests that quality and/or focus (defocus) of retinal imagery is involved in this feedback mechanism and that experimentally induced myopia might be enhanced, reduced or eliminated by pharmaceutical application. Direction of defocus may affect the rate of posterior segment growth, and thus the rate of ocular axial elongation.     

Status of eye health among tribal school children in South India

Purpose:Global trends show a high prevalence of refractive errors among children. The prevalence of vision impairment due to uncorrected refractive errors among school children is increasing and the need for management of other ocular conditions is also reported. This study presents the status of eye health and pattern of daily activities among the school children of a tribal location in Tamil Nadu, South India.Methods:A cross-sectional study was conducted in 13 schools of Karumandurai cluster, Salem district in Tamil Nadu, India. A three-phased comprehensive school screening protocol was conducted to understand the prevalence of vision impairment, refractive error, and other ocular conditions along with a survey about the daily activities of the children at school and home.Results:Among the 3655 children screened, the prevalence of vision impairment was found to be 0.62% (n = 23, 95% confidence interval [CI] 0.42–0.94) and prevalence of refractive error was 0.30% (n = 11, 95%CI 0.17–0.54), among which 0.11% (n = 4) were already wearing spectacles. A total of 44 children (1.20%; 95%CI 0.90–1.61) were found to have other ocular problems and among them, 14 (0.38%) had visual acuity less than 20/30 (6/9). Almost 84% of children required surgical or specialty eye care services. Vision impairment was more in children with other ocular conditions compared to refractive errors (P < 0.001).Conclusion:The prevalence of vision impairment and refractive errors in this tribal area was less. Ocular conditions were more prevalent than refractive errors in this tribal region with the majority of children needing specialty or surgical eye care services. This implies the need for access to secondary or tertiary eye care centers.     

近视眼眼球突出度及相关研究

目的探讨眼球突出度、等效球镜度数、眼轴长度之间的相关性。方法近视患者及正视者189例,散瞳检影验光进行屈光度检查,采用Hertel眼球突出计测量眼球突出度,相干光生物测量仪（IOL—master）测量角膜曲率、眼轴长度。按眼轴长度不同分正视及轻度近视组、中度近视组、高度近视组。均取右眼进行各组之间眼球突出度比较,分析眼球突出度、等效球镜度数、眼轴长度三者之间关系。结果正视及轻度近视组眼轴〈25．00mm,平均（23．54±0．73）mm,等效球镜度数为（-0．76±1．29）D。中度近视组眼轴长度25．00～27．00mm,平均（25．77±0．53）mm,等效球镜度数为（-5．33±237）D。高度近视组眼轴≥27．00mm,平均（30.08±209）mm,等效球镜度数为（-15．92±5．12）D。正视及轻度近视组平均眼球突出度为10．50～19．50mm,平均（14．66±1．94）mm,中度近视组平均眼球突出度为13．00～19．50mm,平均（16．16±1．40）mm,高度近视组平均眼球突出度为14．00～23．00mm,平均（18．30±1．63）mm。高度近视组眼球突出度分别大于中度近视组、正视及轻度近视组（P〈0．01）。中度近视组眼球突出度大于正视及轻度近视组（P〈0．01）。眼球突出度、等效球镜度数、眼轴三者之间存在线性相关关系,一元线性回归方程分别为眼球突出度=0．616×AL（眼轴长度）（R^2=0．990,F=18450．30,P〈0．01）;眼球突出度=14．65—0．227×SE（等效球镜度数）（R^2=0．500,F=187．05,P〈0．01）;等效球镜度数=52．06—2．24×AL（眼轴长度）（R^2=0．892,F=1537．83,P〈0．01）。结论随着眼轴长度、等效球镜度数增加,近视眼眼球突出度随之线性增加。随着眼轴增长眼球向后扩张、眼球向前突出,眼球向前突出更为明显。（中华腰科杂志,2007,43：525-529）