准分子激光手术在矫治儿童严重屈光参差性弱视中的作用

儿童严重屈光参差患者的弱视发生率高达66.67%,其中28.30%患儿终致视力残疾.近十年准分子激光手术矫治儿童严重屈光参差的研究表明,该手术是安全、有效的,可预测性及稳定性均较好,为儿童屈光参差性弱视治疗提供了一个良好的条件.术后进行规范的弱视治疗,提高了治愈率,降低了致残率.然而,儿童屈光手术矫治起始年龄、等值球镜的矫治范围、术后角膜剩余厚度等有待规范.术后儿童角膜修复机制的研究有待深入.     

先天性白内障手术时机及疗效分析

目的探讨先天性白内障手术的时机及疗效。方法62例(102眼)先天性白内障施行透明角膜切口白内障摘出或联合人工晶状体植入术。结果62例(102眼)术后视力有明显提高。除31眼因年龄小不能配合视力检查外,其余71眼术后矫正视力0.02~0.25者20眼(28.17%);0.3~0.5者25眼(35.21%);0.6~1.0者21眼(29.58%);1.0~1.5者5眼(7.04%);术后并发症主要有角膜水肿、虹膜后粘连、人工晶状体瞳孔夹持、后发性白内障和人工晶状体“茧样膜”形成。结论由于先天性白内障可导致儿童不可逆的视觉损伤,因此早期治疗是必要的,且越早越好。单眼白内障无论年龄大小均应行人工晶状体Ⅰ期植入;3岁以下的双眼先天性白内障可先行白内障摘出,学龄前行人工晶状体Ⅱ期植入,术后采取积极的光学矫正措施和弱视训练。     

弱视患者视网膜厚度的差异观察

目的:探讨不同程度远视而引起的弱视患者的视网膜神经纤维层厚度的差异。方法:采用视网膜厚度分析仪(Retinal thickness analyzer RTA)测量弱视患者22例(31眼)的视网膜神经纤维层厚度,所得图象经计算机处理后得出相应的视网膜厚度值与厚度地形图,数据经SPSS统计软件包进行分析。结果:弱视患者视网膜平均厚度为176.45±27.36μm。不同程度的弱视患者各点间视网膜厚度无明显差异性。弱视患者的不同远视程度与视网膜厚度相关系数r=0.056。结论:不同程度的弱视患者各点间视网膜厚度无明显差异性。弱视患者的不同远视程度与视网膜厚度无明显相关性。     

Accommodative stimulus/response function in human amblyopia

Three parameters are essential to describe static accommodative behavior in a comprehensive, quantitative manner: the slope of the stimulus/response curve, the depth of focus, and the tonic response. These parameters were obtained in amblyopes, former amblyopes, strabismics without amblyopia, and normals. Results showed that the accommodative response in the amblyopic eye was characterized by a reduction in the slope of the stimulus/response curve and increased depth of focus. Similar abnormalities but of lesser magnitude were found in the non-dominant eye of some former amblyopes and some strabismics without amblyopia. Orthoptic therapy always increased the slope of the stimulus/response curve in the amblyopic eye. We believe that the reduced accommodative responses found in amblyopic eyes reflect a primary sensory loss over the central retinal region that occurs as a result of prolonged, early, abnormal visual experience associated with the presence of strabismus and/or anisometropia.     

AMBLYOPIA IN THE FOUR TO NINE YEAR AGE GROUP. A FOUR-YEAR SURVEY

A guide to the ophthalmologist in the choice of the older child with amblyopia most likely to respond to active intensive visual stimulation in short bursts is presented. A series of 99 children treated on a CAM vision-stimulator is described. Visual improvement of at least two rows of letters on the Snellen chart was maintained for at least three years after treatment in 62% of these patients aged between five and nine years with visual fixation within 3^° of the fovea. Amblyopia following minor trauma or minor pathology also responded well. Children maintaining the visual improvement were those with esophoria up to 13^°. those with hypermetropia up to 11.0 D and those with astigmatism of 1.5 D. Also responding well were children with anisometropia with up to 3.0 D of either hypermetropia or astigmatism     

Ophthalmological examination of the infant. Developmental aspects

In recent years, the ophthalmic examination of infants has been of increasing interest to both clinicians and vision researchers. Clinicians have documented a greater risk of retinopathy, strabismus and amblyopia in premature infants, especially those of low birthweight. In addition to the external and retinal examination of the infant eye, a number of clinical tests can help the ophthalmologist to detect visual dysfunction through the evaluation of pupillary responses and ocular motility. Recently, the development of objective techniques (optokinetic nystagmus, forced choice preferential looking, and visually evoked potentials) have not only aided in the detection of ophthalmic disorders in infants; they have contributed to useful definitions of “normal” vision at various ages and to the understanding of factors that influence the pre- and post-gestational development of visual function.     

THE CAT AS A MODEL FOR VISUAL DEPRIVATION

Both behavioural and neurophysiological changes can be observed in cats that have experienced interference with their normal visual environment. This visual deprivation may result from alterations to the path of light forming the normal image on the retina, and includes changes that cause the image to fall on an inappropriate part of the retina so that normal binocular interactions are affected. While some neurophysiological changes can be observed at the level of the lateral geniculate nucleus they become more prominent as information reaches the visual cortex, where cells commonly receive neural excitation from both eyes and require the information to come from corresponding parts of the two retinas and that the stimulus should have appropriate orientation and direction of movement. Many of the observations of deprivation in animals have clear parallels in the human environment.     

准分子激光原位角膜磨镶术治疗视觉敏感期后远视性屈光参差性弱视

目的评价准分子激光原位角膜磨镶术（laser in situ kemtomileusis，LASIK）治疗视觉敏感期后远视性屈光参差性弱视1年后的作用和安全性。方法对25例（25眼）年龄为12—16岁的远视性屈光参差性弱视患儿行角膜中央最薄处厚度和中央2．5mm外四个方位厚度检测、1％阿托品散瞳验光、角膜直径测量、wavefront或OPD—scan波前像差仪进行坐位时的虹膜识别后行LASIK治疗。弱视眼屈光度远视1．50—7．50DS，散光为1．00-5．00DC，激光仪使用visxstarS4或NidekEC5000 CX—Ⅱ激光仪，两种激光均具有眼球主动追踪和虹膜识别技术。术后辅助弱视训练，随访12个月以上。结果弱视眼远视切削均值达（3．75±1．20）D，最高限度为6，75DS，术中术后无角膜瓣相关并发症发生。术后第12个月随访时，术眼残余屈光度均值（1.09±1．13）D（P〈0．01），最佳矫正视力由0．24±0．17提高至0．67±0．37（P〈0．01），无最佳矫正视力下降或丢失。结论视觉敏感期后的弱视仍具有可塑性，术后1年的随防表明LASIK治疗远视性屈光参差性弱视安全、有效。     

The effect of prolonged monocular occlusion on latent nystagmus in the treatment of amblyopia

We recorded eye movements in 5 patients with latent nystagmus (LN) before and after 2 days of occlusion of the better eye. The slow-phase speed of the nystagmus (SPS) was in general, before occlusion, lower when the better eye fixated but, after occlusion, lower when the worse eye fixated. However, the sum of SPS during right fixation and SPS during left fixation remained constant. Oscillopsia complaints gradually disappeared during the period of occlusion. These findings indicate that the difference between the SPS during fixation with the right eye and the SPS during fixation with the left eye in LN patients is caused by a compensatory drift that decreases LN during fixation with the better eye but increases LN during fixation with the worse eye. During occlusion, this compensatory drift changes its direction and magnitude slowly over days. Hence, occlusion of the better eye in children with amblyopia and LN should be prescribed only in days per week, not in hours per day.     

LASEK手术在治疗成年人屈光性弱视中的作用

目的观察准分子激光上皮下角膜磨镶术(LASEK)在治疗成年人屈光性弱视中的作用。设计前瞻性病例系列。研究对象55例(97眼)行LASEK治疗的屈光性弱视患者。方法记录上述患者LASEK手术前后最佳矫正视力(BCVA)、屈光度变化,并进行比较分析,术后随访1年。主要指标手术前后BCVA及屈光度。结果术后1周所有患者裸眼视力(UCVA)均明显提高,8眼(8.25%)超过术前BCVA。术后1个月BCVA由术前(0.51±0.12)提高到(0.61±0.16),两者相比具有显著性差异(P=0.000),且26眼(26.80%)UCVA>0.8。3个月时视力基本稳定,81眼(83.51%)超过术前BCVA,40眼(41.24%)UCVA>0.8。术后6个月(0.71±0.18)与术后1年(0.72±0.18)比较差异无统计学意义(P=0.610)。术后1周时复查患者出现轻度远视,术后1周等效球镜值(+1.25±0.48)D,1个月等效球镜值(+0.99±0.45)D,在术后3个月屈光度值预期基本接近;术中及术后无严重并发症发生。结论 LASEK可以有效矫正成年人屈光性弱视的屈光度,提高矫正视力,可以明显改善弱视。