立体视锐度的临床检查及评价

用中国科学院生物物理研究所研制的ＳＶＴ软件包及Ｌａｎｇ、颜氏图、Ｔｉｔｍｕｓ，对２４３例正常学龄前儿童和１１７例斜视弱视患儿立体视锐度进行了测定，结果表明，正常学龄前儿童中９３．８２％（ＳＶＴ）、９１．７７％（颜氏图）立体视锐度≤６０〃，用Ｔｉｔｍｕｓ检查≤６０〃者为７０．３７％，斜视弱视组患儿立体视觉异常者（＞６０〃及立体视盲者）均≥９０％；所有检查方法两组间结果均有显著性差异（ｐ＜０．０１），说明ＳＶＴ立体视觉检查方法可以用于检测立体视觉异常或儿童立体视觉异常的筛选；并通过几种方法结果的比较证明对学龄前儿童立体视发育进行研究时，选用随机点立体图检查方法更为合适。     

不同类型弱视儿童立体视觉状况的临床观察

目的：了解不同类型弱视儿童立体视觉状况及危害,为提高临床弱视治愈率提供依据。

方法：选取321例在我院门诊确诊为不同类型弱视的儿童,应用同视机随机点立体图行远立体视觉检查,颜少明随机立体检查图行近立体视觉检查,分别检测其近零视差立体视锐度、交叉视差及非交叉视差立体感知度,并对资料数据进行统计分析。

结果：屈光不正性弱视组、屈光参差性弱视组与斜视性弱视组及形觉剥夺性弱视组比较,患儿的近零视差、交叉视差、非交叉视差及远立体视存在率的差异均有统计学意义(P<0.05)。其中斜视性弱视组及形觉剥夺性弱视组患儿的立体视觉存在率最低,但两者之间比较差异无统计学意义(P>0.05),屈光不正性弱视组患儿立体视觉存在率最高,屈光参差性弱视组患儿立体视觉存在率较屈光不正性弱视组低。

结论：不同类型的弱视均可导致儿童立体视觉的发育障碍,其中斜视性弱视及形觉剥夺性弱视对立体视觉影响最大,屈光不正性弱视影响较小,重视立体视觉的重建是巩固儿童弱视治疗的关键。     

儿童弱视兴立体视锐度

目的 了解儿童弱视兴立体视锐度的关系。方法 对346例正常及弱视儿童立体视锐度采用颜少明近用定量随机点立体圆进行检查，比较弱视组各类型弱视立体视锐度情况。结果 346例中，168例正常儿童中获得正常立体视锐度为122例（76.62%)，178例弱视儿童中儿得正常立体视锐度为8例（4.49%)，各类型弱视立体视锐度比较，其中形觉剥夺性弱视立体视锐度最差，其次为斜视性弱视、屈光参差性弱视，屈光不正性弱视。结论 弱视患儿立体明显低于正常儿童立体视，弱视程度越重，立体视越差。     

儿童弱视与立体视锐度

目的 了解儿童弱视与立体损锐度的关系。方法 对346例正常及弱视儿童立体视锐度采用颜少明近用定量随机点立体图进行检查,比较弱视组各类型弱视立体视锐度情况。结果 346例中,168例正常见童中获得正常立体视锐度为122例(72.62％),178例弱视儿童中获得正常立体视锐度为8例(4.49％),各类型弱视立体锐度间比较,其中形觉剥夺性弱视立体视锐度最差,其次为斜视性弱视、屈光参差性弱视,屈光不正性弱视。结论 弱视患儿立体视明显低于正常儿童立体视,弱视程度越重,立体视越差。     

不同类型及程度弱视患儿的立体视觉现状评价

目的了解不同类型弱视及不同程度弱视儿童的立体视觉损害情况。方法对178例初诊的不同类型弱视儿童,采用颜少明立体视觉检查图对弱视儿童分别检测其近零视差立体视锐度、交叉视差及非交叉视差立体感知度。结果屈光不正性弱视组、屈光参差性弱视组、斜视性弱视组3组之间近零视差、交叉视差、非交叉视差存在率的差异均有统计学意义（P〈0.05）,屈光不正性弱视组轻度弱视和中度弱视之间比较,近零视差及交叉视差的差异均无统计学意义（P〉0.05）。结论弱视导致儿童立体视觉的发育障碍,且随弱视程度的加重而增加,屈光不正性弱视对立体视觉的影响程度相对较轻,斜视性弱视重,屈光参差性弱视介于二者之间。     

屈光不正性弱视治愈前后立体视觉的临床初步观察

目的 了解屈光不正性弱视儿童在治疗前和治愈后立体视觉状况.方法 对43例屈光不正性弱视儿童分别在治疗前和治愈后采用颜少明<立体视觉检查图>检测其立体视锐度以及同视机三级功能的检测.结果 (1)弱视患者治愈前(矫正视力0.1～0.8)后(矫正视力0.9～1.5)黄斑视锐度和周边立体视锐度的结果在统计学上的差异有显著性(P＜0.05),(2)弱视患者治愈前后融合范围和定性远立体视的结果在统计学上均无统计学意义(P＞0.05).结论 (1)屈光不正性弱视不仅影响视力发育同时也影响整体立体视的发育.(2)随着视力的治愈整体立体视锐度也有显著的改善.(3)在弱视的诊断治疗中注意整体立体视的变化.     

影响屈光性调节性内斜视立体视锐度发育因素分析

目的分析影响屈光性调节性内斜视患者立体视锐度发育的因素。方法对100例屈光性调节性内斜视按斜、弱视常规戴镜的原则进行治疗;采用同视机测量斜视度数;用颜少明的立体视觉检查图测量近立体视锐度。结果屈光性调节性内斜视患者发病年龄越小、戴镜前斜视度越大、两眼视力差距越大,立体视锐度的发育越差。结论屈光性调节性内斜视患者的立体视锐度发育与发病年龄、戴镜前斜视度、两眼视力有关。     

不同类型及程度弱视儿童的立体视觉

目的 了解不同类型及程度弱视儿童的立体视觉状况.设计 回顾性对比临床分析.研究对象 北京同仁医院眼科中心89例屈光不正性弱视、45例屈光参差性弱视及39例斜视性弱视儿童.方法 采用颜少明随机立体检查图和同视机三级功能检查,对三种弱视儿童分别检测其近零视差立体视锐度、交叉视差及非交叉视差立体感知度、远立体视和融合范围.主要指标 近零视差、交叉视差、非交叉视差、远立体视和融合范围.结果 屈光不正性弱视及屈光参差性弱视儿童中,轻度弱视近零视差、交叉视差均优于中度弱视(P均＜0.05);斜视性弱视儿童中,中度弱视远立体视优于重度弱视(P＜0.05);轻度、中度屈光不正性弱视、屈光参差性弱视的远融合范围均无显著性差异,中度、重度斜视性弱视的远融合范围也无显著性差异(P均＞0.05).结论 弱视影响儿童期立体视觉的发育,且随弱视程度加重而增加.对立体视觉的影响程度,屈光不正性弱视轻,斜视性弱视重,屈光参差性弱视介于二者之间.(眼科,2008,17:59-62)     

双眼视觉训练对间歇性外斜视儿童术后双眼视功能重建的疗效观察

目的:观察双眼视觉训练对间歇性外斜视儿童术后双眼视功能重建的疗效。方法:将2010-01/2011-10收治的112例间歇性外斜视患儿,术后分为3组,第1组采用同视机进行双眼视觉训练,第2组采用视知觉学习训练软件进行双眼视觉训练,第3组为对照组,未进行双眼视觉训练。对三组患儿术后视远、视近立体视锐度及术后1a眼位正位率进行观察比较。结果:两组视觉训练患儿视远、视近立体视锐度显著高于对照组,差异有显著性。在术后1a随访时,对照组眼位正位率显著低于其他两组。结论:间歇性外斜视患儿术后进行双眼视觉训练,可显著促进患儿双眼视功能的重建,降低眼位回退率,提高手术成功率。     

山东滕州市农村小学生弱视斜视及立体视锐度调查

目的 调查滕州市农村小学生的视力、立体视锐度及弱视和斜视的患病情况,并对Titmus立体视图检查法、视力检查法、Titmus立体视图联合视力检查法三种弱视筛选试验进行评价.方法 应用随机整群抽样调查方法,共抽取滕州市8所农村小学,共有小学生2742人,年龄5～14岁,平均(9.3±2.3)岁.进行Titmus立体视图、裸眼视力、眼位及眼球运动检查,对任一眼裸眼视力<1.0者进行视网膜检影验光.结果 (1)小学生视力低常率为13.83%,从7岁至13岁视力低常率呈逐渐上升趋势;视力低常的首位原因为屈光不正,弱视,其中近视占79.67%(486眼/610眼);(2)弱视患病率为1.50%.97.5%(39/40)的弱视患儿为首次被筛查出来;斜视患病率为1.72%;(3)非弱视/斜视儿童的立体视锐度5岁年龄组为60″,6岁年龄组为50″,7岁及以上年龄组均为40″;弱视患者中立体视锐度异常者占77.5%(31140),斜视患者中立体视锐度异常者占28.3%(13/46);(4)Titmus立体视图联合视力检查法筛选弱视的特异度(99.47%)及粗一致性(99.06%)最高,误诊率(0.53%)最低;其次为Titmus立体视图检查法(特异度为97.98%;粗一致性为97.59%;误诊率为2.02%);视力检查法的特异度(87.47%)及粗一致性(87.66%)最低,误诊率(12.53%)最高.结论 滕州市农村小学生视力低下的首位原因为近视;弱视和斜视是影响立体视觉发育的主要因素;Titmus立体视图联合视力检查法可提高学龄儿童弱视筛选的效率.     

Segmentation and accuracy in copying and drawing: Experts and beginners

As part of an ongoing investigation into real-world copying and drawing, I recorded the eye-hand drawing strategies of 16 subjects with drawing experiences ranging from expert to novice while they copied a line drawing of a standing nude. The experts produced accurate copies whereas all the beginners produced marked inaccuracies of overall scaling, proportion and shape. Analysis of eye and hand movements showed that the experts alone segmented the original drawing into simple line sections that were copied one at a time using a direct eye-hand strategy not requiring intermediary encoding to visual memory. The results suggest that segmentation into simple lines defines the task-specific process of accurate copying, and that this process is restricted to experts, i.e. acquired through training and practice. Additional preliminary tests also suggest that a similar process may apply to drawing a model from life.     

Proximal and accommodative convergence and age

The authors have estimated the phoria for distant and near fixation in two groups of subjects (mean age 27.5 ± 4.4 and 59.2 ± 8.2 years). Different accommodative stimuli were induced by adding minus lenses for distant fixation and plus lenses for near fixation. Statistical analysis of the experimental data indicates that, for distant fixation, the value of phoria per unit of accommodative stimulus is significantly lower in presbyopic than in nonpresbyopic subjects. Also, during near fixation, the accommodative convergence (AC/A ratio) is more reliable in the presbyopic subjects when the accommodative stimulus is progressively reduced. This varying behavior indicates in presbyopic subjects that proximal convergence is of greater relative importance in the determination of the fusion-free position. In nonpresbyopic subjects, accommodative convergence is the more important component.     

Anesthesia and preoperative and postoperative medications

Although certain methods such as retrobulbar blocks are used extensively, improvements in procedure can always be implemented. The use of ultrasound, low concentrations of anesthesia, careful monitoring, and, in the case of risk patients, anesthesia standby are all important considerations to ensure uneventful treatments. Topical anesthesia eliminates needle risk as well as risk of ptosis and bruising. Because it has been demonstrated that bacteria routinely enter the anterior chamber during uncomplicated cataract surgery, certain irrigation solutions are helpful, but still debatable. Postoperatively, diclofenac, flurbiprofen, and timolol have all been proven to be effective in reducing ocular inflammation, reducing incidence of CME, and controlling pressure increase, respectively.     

Anesthesia and preoperative and postoperative medications

Retrobulbar blocks, although widely used, still have potentially serious complications. Topical anesthesia presents less risk of injury to the globe and less pain but requires careful usage and an experienced surgeon. New techniques, however, allow for an increase in the percentage of patients able to have topical anesthesia. Preoperatively, 2.5% phenylephrine is found to be just as effective as 10% phenylephrine, and, when compared with wound closure and surgeon's experience, the effect of prophylactic medications was found to be negated. Postoperatively, diclofenac is found to be as effective an anti-inflammatory agent as prednisolone. Also, the addition of 10% phenylephrine to 4% pilocarpine drops enhances the effectiveness of pharmacologic treatment of postoperative iridocorneal adhesions. In addition, ophthalmologists should be aware of emerging antibiotic resistance.     

Paraneoplastic and non-paraneoplastic retinopathy and optic neuropathy: Evaluation and management

Paraneoplastic syndromes involving the visual system are a heterogeneous group of disorders occurring in the setting of systemic malignancy. Timely recognition of one of these entities can facilitate early detection and treatment of an unsuspected, underlying malignancy, sometimes months before it would have otherwise presented, and gives the patient an increased chance at survival. We outline the clinical features, pathogenesis, and treatment strategies for the retinal- and optic nerve–based paraneoplastic syndromes: cancer-associated retinopathy; melanoma-associated retinopathy; paraneoplastic vitelliform maculopathy; bilateral diffuse uveal melanocytic proliferation; paraneoplastic optic neuropathy; and polyneuropathy, organomegaly, endocrinopathy, monoclonal gammopathy, and skin changes syndrome. Distinguishing these disorders from their non-paraneoplastic counterparts (e.g., autoimmune-related retinopathy and optic neuropathy, and acute zonal occult outer retinopathy) and determining appropriate systemic evaluation for the responsible tumor can be challenging. In addition, we discuss the utility and interpretation of autoantibody testing.     

Nodes and nodal points and lines in eyes and other optical systems

The typical stigmatic optical system has two nodal points: an incident nodal point and an emergent nodal point. A ray through the incident nodal point emerges from the system through the emergent nodal point with its direction unchanged. In the presence of astigmatism nodal points are not possible in most cases. Instead there are structures, called nodes in this paper, of which nodal points are special cases. Because of astigmatism most eyes do not have nodal points a fact with obvious implications for concepts, such as the visual axis, which are based on nodal points. In order to gain insight into the issues this paper develops a general theory of nodes which holds for optical systems in general, including eyes, and makes particular allowance for astigmatism and relative decentration of refracting elements in the system. Key concepts are the incident and emergent nodal characteristics of the optical system. They are represented by 2 × 2 matrices whose eigenstructures define the nature and longitudinal position of the nodes. If a system's nodal characteristic is a scalar matrix then the node is a nodal point. Otherwise there are several possibilities: Firstly, a node may take the form of a single nodal line. Second, a node may consist of two separated nodal lines reminiscent of the familiar interval of Sturm although the nodal lines are not necessarily orthogonal. Third, a node may have no obvious nodal line or point. In the second and third of these classes one can define mid-nodal ellipses. Astigmatic systems exist with nodal points and stigmatic systems exist with no nodal points. The nodal centre may serve as an approximation for a nodal point if the node is not a point. Examples in the Appendix , including a model eye, illustrate the several possibilities.     

Sensitivity to first- and second-order motion and form in children and adults

We compared the sensitivity of adults and children aged 3-10 years to first- and second-order motion and form. For first-order stimuli, at all ages sensitivity was better for motion than form, and motion thresholds were better at 6 Hz than at 1.5 Hz. For second-order stimuli, at all ages sensitivity was better for form than motion, and motion thresholds were better at 0.25 cyc/deg than at 1 cyc/deg. Thresholds became adult-like later for motion than for form and later for first-order than second-order stimuli. For first-order stimuli, the changes with age were larger and more protracted.     

Estrogen and progesterone receptors and human conjunctiva

Freshly frozen conjunctival tissue from premenopausal and postmenopausal women and male subjects were processed for estrogen and progesterone receptors by using monoclonal antibodies and a peroxidase-antiperoxidase technique. No immunocytochemical staining was localized in the nuclei of the cells treated with the monoclonal antibodies to human estrogen receptor or human progesterone receptor in any of the conjunctival specimens, in contrast to the strongly positive staining in breast adenocarcinoma controls. Immunocytochemical staining disclosed no evidence for estrogen or progesterone receptors on cells of the ocular surface.