青少年共同性斜视矫正术后眼位偏差的临床分析

目的 探讨青少年共同性斜视术后眼位矫正偏差的发生原因和影响因素。方法 对８８例共同性斜视手术后晚期存在眼位偏差的１９例患者分别进行了手术年龄、斜视类型、眼轴长度、术后时间及术眼视觉功能等方面的比较观察和临床分析。结果 通过对本组的资料分析发现,年龄愈小发生术后眼位偏差的机会愈大,内科以矫正过度多见,外支矫正不足多见;斜视术后眼球有向外偏移和眼球向术前回复的倾向;眼轴长度对术后眼位偏差没有显著影响;     

明视、暗视及药物散瞳状态下的瞳孔位置

目的观察明视、暗视及药物散瞳状态下的瞳孔位置,评价瞳孔位置是否随瞳孔直径而改变及其与年龄、屈光不正等因素的相关性。方法运用Asc lep ion波前像差仪检测获得130例(130眼)屈光不正患者在明视、暗视及药物散瞳状态下的眼前节图像,设计软件计算图像中的瞳孔中心位置、角巩膜缘几何中心位置。结果随着瞳孔直径的增大,瞳孔中心位置始终向颞侧偏移。从明视到暗视,瞳孔直径平均由4.06 mm增至6.37 mm,而瞳孔中心平均向颞侧移动0.133 mm(t=4.604,P<0.01);从暗视到药物散瞳状态,瞳孔直径平均由6.37 mm增至7.58 mm,而瞳孔中心平均向颞上方移动0.162 mm(t=4.180,P<0.01);从明视到药物性散瞳,瞳孔中心平均向颞上方移动0.183 mm(t=7.378,P<0.01);但瞳孔中心位置的移动量与年龄、屈光不正度及瞳孔直径的改变值无显著相关性。结论瞳孔中心位置随着瞳孔直径的增大而主要向颞侧偏移同时略向上移动,但总的移动量不大。     

缩瞳前后瞳孔中心偏移对有晶状体眼前房人工晶状体定位的影响

目的:通过测量缩瞳前后瞳孔中心偏移方向及偏移量,探讨其对有晶状体眼前房人工晶状体植入术中晶状体定位的影响和改进的方法。方法:选取26例52眼健康眼,年龄18～78岁,用10g/L匹罗卡品眼水滴眼缩瞳,留取缩瞳前后的眼部照片,并使用AutoCAD软件分析测定缩瞳前后的瞳孔中心相对位置。结果:52眼正常状态瞳孔中心位于鼻上方,10g/L匹罗卡品眼水缩瞳后瞳孔中心仍位于鼻上方,平均方向为向上方偏移,缩瞳前后平均偏移量为0.18mm,最大偏移量0.62mm。结论:缩瞳前后瞳孔中心均有不同程度的偏移,所以,在有晶状体眼前房人工晶状体植入术前,做角膜标记,且行角膜标记的时机要在缩瞳前,这样会大大减少晶状体偏中心的发生机会及晶状体偏中心严重程度。     

间歇性外斜视患者知觉眼位和主观斜视角的比较

目的：通过和同视机主观斜视角比较,了解间歇性外斜视患者知觉眼位的情况和意义。方法：系列病例研究。对2017年2-8月在北京同仁医院的间歇性外斜视患者分别用同视机检测其主观斜视角和用基于计算机平台的视感知觉检查方法检测其知觉眼位,将同时具备以上2项检测结果的患者作为研究对象。对二者水平方向眼位进行线性相关分析;统计同视机主观斜视角在垂直方向眼位偏斜的检出率,对同视机主观斜视角未检出垂直偏斜者分析其垂直知觉眼位的分布情况;对水平和垂直知觉眼位进行线性相关和回归分析。结果：共有120例间歇性外斜视患者被纳入研究。在水平方向,主观斜视角为（-8.1±5.3）°,知觉眼位偏移值为（332±233）像素,同视机主观斜视角越向外偏移,水平方向的知觉眼位偏移越大（r=-0.383,P<0.001）。在垂直方向,3例（2.5%）同视机检测到眼位偏斜,117例未检测出垂直眼位偏斜者中有113例（94.2%）可检测出不同程度的知觉眼位偏差,为（22±29）像素,其中67.5%（81/120）≤26像素（垂直眼位偏斜在0.5°以内）,有82.5%（99/120）≤53像素（垂直眼位偏斜在1°以内）。120例患者垂直方向知觉眼位偏移为（24±32）像素,它与水平方向知觉眼位偏移呈线性相关关系（r=0.373,P<0.001）,线性回归方程为垂直知觉眼位偏移=6.403+0.052×水平知觉眼位偏移（F=19.093,P<0.001）。结论：同视机主观斜视角与知觉眼位偏移均能反映间歇性外斜视患者双眼分视状态下水平方向的眼位偏斜状态;知觉眼位检查在垂直方向的眼位偏斜检出率明显高于同视机;垂直方向的知觉眼位偏斜随着水平方向知觉眼位偏斜的增加而增大。     

光亮度变化对虹膜定位波前引导LASIK手术的影响

目的 探讨准分子激光原位角膜磨镶术（LASIK）术中光线亮度改变对眼球旋转角度和瞳孔中心的影响.方法 前瞻性病例系列研究.LASIK患者140例（268眼）,术中通过调整激光机灯光亮度,以虹膜定位技术（VisxStar-S4-IR）分别测出高亮度和低亮度下眼球的旋转角度、瞳孔大小、瞳孔直径及瞳孔中心位置,并进行比较分析.在与基础眼位相比及亮度变化之间,眼球旋转方向在两眼的差异采用卡方检验;眼球旋转角度、瞳孔直径改变在两种亮度状态下的差异采用独立样本t检验.结果 灯光亮度改变后,268眼中有259眼（占96.6%）发生了眼球旋转,而且主要为外旋（180眼,69.5%）,其中有26眼（占10.0%）眼球旋转方向发生改变.大部分眼（247眼,占95.4%）旋转角度≤2°,且与基础眼位比较,右眼与左眼低亮度下的旋转角度大于高亮度（t=2.375、2.146,P均＜0.05）.在高亮度和低亮度下,患眼瞳孔直径分别为2.00～4.10 mm和2.40～5.80 mm,差异有统计学意义（t=2.1l,P＜0.05）.在高亮度和低亮度下,与术前检查结果相比,约2/3眼的瞳孔中心均向鼻上方偏移,但两种光亮度之间瞳孔中心的偏移差异无统计学意义.结论 准分子激光屈光手术中,亮度的改变会引起眼球旋转和瞳孔中心位置的改变,从而影响手术矫正的准确性.     

Medpor下睑插片植入治疗下睑退缩

目的评价Medpor下睑插片作为下睑植入物治疗先天性及后天性下睑退缩的效果。设计回顾性病例系列研究。研究对象33例患者36眼，其中先天性下睑退缩4例6眼，后天性者29例30眼。方法术前测量在第一眼位下睑相对角膜下缘的位置及距下眶缘的位置。手术采用下睑袋皮肤切口，打开眶隔，视患者下睑退缩程度修剪Medpor下睑插片的形状及大小，将植入物置于下睑板下缘及眶下缘骨缘之间。术后观察植入物是否移位或脱出。术后2周及3个月时测量下睑位置，观察其变化情况。主要指标第一眼位下睑位置。结果对33例36眼行Medpor下睑插片植入者随访6～24个月，无植入物脱出及移位。34眼在第一眼位下睑位于角膜缘或角膜下缘上0．5mm，2眼仍残存≥1mm的下睑退缩。结论Medpor下睑插片作为植入物可提供下睑长期的支撑，可达到良好的功能及美容效果。Medpor下睑插片可作为治疗下睑退缩的较理想植入物。     

模拟眼记录跳水运动入水眼压变化的试验研究

目的为了降低跳水运动所致视网膜脱离的高发病率,通过研制压力感受器模拟眼,研究不同情况下模拟眼眼压曲线的影响因素,提出眼防护措施。设计实验研究。研究对象内置压力传感器的模拟眼。方法模拟眼由硅胶制成,内置压力传感器,其量程为0~800mmHg,采样频率为512Hz。模拟眼置于模拟头的突出程度分别为-3.5mm、0mm、5mm、10mm,内置模拟眼跳水整体装置的重量分别为6kg、11kg、16kg、26kg。试验跳台为10m、5m、3m。跳水入水角度为正常垂直入水及平拍入水。主要指标模拟眼眼压曲线。结果模拟眼记录的眼压有两个时段,先出现的瞬间冲击压为振荡峰压,后出现的静水压为逐渐上升至平台的曲线。在正常体位入水时,瞬间冲击压总是小于静水压,眼球突出程度对瞬间冲击压无明显影响;随着跳水高度、跳水负重的增加,瞬间冲击压也随之增加。而平拍入水时,在10m跳台、负重16kg,入水瞬间眼压达520mmHg,明显高于静水压。结论跳水入水角度是影响瞬间模拟眼眼压最重要的因素。建议跳水失误时应用手臂护眼,可有效减少眼损害。     

外直肌超常量后徒治疗外斜视

目的：探讨超常量外直肌后徒术治疗外斜视的方法及效果。方法：对28例（54眼）共同性外斜视及麻痹性外斜视患者行外上直肌超常量后徒手术,单眼或双眼外直肌后徒11－15mm。结果：术后眼位矫正良好,其中13眼出现不同程度的外转受限,结论：该手术方式简便,避免损伤过多的眼外肌,术后效果满意。     

匹羅卡品對近視眼瞳孔中心位置的影響

目的探討縮瞳劑對瞳孔中心位置的影響及其在PRK和LASIK術中舆激光切削中心偏移的關系.方法對46例(92眼)凝行PRK和LASIK手術的近視眼患者以1%及2%硝酸匹羅卡品眼液點眼,在角膜地形圖上自動測量縮瞳前後的角膜直徑、瞳孔中心偏離角膜光學中心的方向和距離.結果自然狀態成年近視眼瞳孔直徑禺水平徑3.86(0.93mm,垂直徑3.96(1.02mm.73.91%的瞳孔中心位于角膜光學中心的鼻上方,平均偏離0.22(0.10mm.1%或2%硝酸匹羅卡品眼液縮瞳後,瞳孔中心平均偏離0.16(0.05mm和0.20(0.10mm.瞳孔中心的象限分布比例舆縮瞳前無明顯差异.結論縮瞳使瞳孔中心相對于角膜光學中心的偏離减少,有利于减少PRK和LASIK術中激光切削中心大多向鼻上方的偏移.縮瞳的實際意義在于便于手術中心的定位.     

斜视患儿知觉眼位和眼球运动与儿童汉语阅读障碍量表间的关联分析

目的：分析斜视患儿知觉眼位、眼球注视运动和眼球扫视运动之间及其与阅读障碍量表评分之间的 关系。方法：病例对照研究。选取2020年6月至2021年6月于深圳市眼科医院就诊的2~6年级斜视 患儿共24例作为斜视组,同期门诊就诊的正常对照组14例。采用视感知觉检查系统评估知觉眼位 偏移,Tobii Eye Tracker 5评估注视和扫视功能,儿童汉语阅读障碍量表（DCCC）进行阅读障碍程度 评测。组间正态分布数据比较采用独立样本t检验,非正态分布数据采用Mann-Whitney U检验进行 差异性比较;水平和垂直方向知觉眼位偏移、注视偏移、扫视偏移与阅读障碍量表得分间的关系采 用Spearman直线相关分析,并对相关分析有统计学意义的指标进一步行线性回归分析。结果：斜视 组知觉眼位明显偏移（P<0.001）。正常组水平扫视与垂直扫视呈较强正相关（r=0.81,P<0.001）,斜 视组呈中等正相关（r=0.64,P=0.001）,且垂直扫视眼位偏移随着水平扫视眼位偏移增加而增大;2 组水平注视与水平扫视呈中等正相关（正常组r=0.64,斜视组r=0.69,均P<0.05）,且水平扫视眼位偏 移随着水平注视眼位偏移增加而增大;在斜视组中水平与垂直知觉眼位、水平注视与垂直注视、水 平知觉眼位与水平注视、水平注视与垂直扫视、DCCC视知觉障碍分量表与垂直扫视呈中等正相关 （r=0.70、0.66、 0.52、0.43、0.47,均P<0.05）,且垂直知觉眼位偏移随着水平知觉眼位偏移增加而增大, 视知觉障碍量表得分随着垂直扫视眼位偏移增加而增大。结论：水平扫视和垂直扫视在眼位正常和 眼位偏斜情况下均存在正相关性;知觉眼位偏移使水平注视、水平扫视和垂直扫视彼此间存在更为 明显的相互影响。在阅读障碍儿童、斜视儿童和正常儿童中均发现扫视运动的异常,本研究发现扫 视垂直方向移位与DCCC分量表中的视知觉障碍分量表具有中等强度相关性,提示扫视功能可能可 以作为评估儿童阅读能力的敏感指标之一。     

Quantitative effect of optic zone diameter changes on rigid gas permeable lens movement and centration

The effect of varying optic zone diameter on rigid contact lens positioning and visible post-blink movement was determined on 20 patients using a 9.50 mm overall diameter lens with 7.40, 7.90 and 8.40 mm optic zones. The smaller optic zone lens positioned more temporally and superiorly than did the larger zone lenses. There was not a strong correlation between lens positioning and patient factors such as corneal shape, corneal apex position, lid position, and corneal diameter. The strongest correlation was between lens position and the patient factors of actual corneal diameter and horizontal apex position. The smaller optic zone lens moved slightly less than did the larger optic zone lenses.     

Computational evaluation of the role of accommodation in pigmentary glaucoma

PURPOSE: Accommodation has been proposed as the cause of the bowing of the posterior iris that occurs in eyes with pigmentary dispersion syndrome. A mathematical model of the anterior eye is needed to explore the elastohydrodynamic effects of accommodation on both the aqueous humor dynamics and the contour of the iris. METHODS: A mathematical model of the coupled aqueous humor-iris system was used to predict the effects of accommodation on the iris position and pressure distribution in the aqueous humor. RESULTS: The mathematical model predicts that accommodation produces a pressure reversal--the anterior chamber pressure being higher than the posterior chamber--and iris movement into a more concave configuration. Total time for accommodation, iris modulus, iris attachment point, and trabecular meshwork permeability all had little or no effect on the iris contour and pressure change. The amount of accommodation, however, had a dramatic effect on both the amount of iris curvature and especially the pressure reversal. For accommodation resulting in a 0.6-mm change in anterior chamber depth, the pressure in the anterior chamber was more than 1.0 mm Hg higher than that in the posterior chamber, compared with a pressure difference of less than 0.1 mm Hg for accommodation resulting in a 0.2-mm change in anterior chamber depth. CONCLUSIONS: The results confirm that accommodation produces bowing of the posterior iris and the magnitude of the bowing is a strong function of the amount of accommodation.     

Ultrasound Biomicroscopy of Iris-claw Phakic Intraocular Lens Implantation

Purpose: To study in situ the intraocular position of iris-claw phakic intraocular lens (ICPIOL) in myopic eyes using ultrasound biomicroscopy (UBM). Methods: UBM echograms of the anterior segment were taken preoperatively and 62 to 115 days postoperatively in 6 eyes implanted with the Verisys ICPIOL (AMO). The echograms were assessed for the effect of the ICPIOL on iris tissue. Results: The preoperative distance between the corneal endothelium and the lens ranged from 2.96 to 3.09 mm, and the postoperative distance between the ICPIOL and the corneal endothelium, from 1.86 to 2.03 mm. The distance between the lens and the posterior surface of the ICPIOL ranged from 0.61 to 0.76 mm. The distance between the superior, inferior optic edge and the iris ranged from 0.49 to 1.00 mm, 0.21 to 0.51 mm respectively. The shortest distance between the ICPIOL haptics and the angle of anterior chamber ranged from 1.25 to 1.65 mm. The indentation of iris tissue by the ICPIOL haptics without pigmentary dispersion and distortion of posterior curvature of iris was observed. Conclusion : Adequate space is maintained between the Verisyse myopic ICPIOL and the corneal endothelium, angle, and crystalline lens. Haptic indentation of the iris without pigment erosion and distortion of iris curvature is noted. The ICPIOL implanted in phakic eyes is a safe alternative for treatment of high myopia.     

Ablation centration after active eye tracker-assisted LASIK and comparison of flying-spot and broad-beam laser

PURPOSE: To evaluate ablation centration of flying-spot LASIK, investigate the effect of patient- and surgeon-related factors on centration, and compare flying-spot and broad-beam laser results. METHODS: This retrospective study comprised 173 eyes of 94 patients who underwent LASIK with the Alcon LADARVision4000 with an active eye-tracking system. The effective tracking rate of the system is 100 Hz. The amount of decentration was analyzed by corneal topography. Patient- (low, high, and extreme myopia; effect of learning) and surgeon-related (learning curve) factors influencing centration were identified. Centration was compared to the SCHWIND Multiscan broad-beam laser with a 50-Hz tracker from a previous study. RESULTS: Mean decentration was 0.36+/-0.18 mm (range: 0 to 0.9 mm). Centration did not differ in low, high, and extreme myopia or in patients' first and second eyes. There were no significant differences in centration between the first 50 LASIK procedures and the last 50 procedures. Comparing flying-spot and broad-beam laser results, there were no differences in centration in low myopia. However, the LADARVision4000 yielded better centration results in high and extreme myopia. CONCLUSIONS: The Alcon LADARVision4000 active eye tracking system provides good centration for all levels of myopic correction and better centration than the Schwind broad-beam Multiscan in eyes with high and extreme myopia.     

Microwave cyclodestruction: evaluation on human eyes.

AIMS--The study was set up to evaluate the effect of microwave cyclodestruction on human eyes. METHODS--Two human eyes were studied. For treatment a horn shaped 5.8 GHz microwave applicator and fibre optic thermometry were used. Just before enucleation, the rectangular (2 x 3 mm) microwave aperture was placed onto the conjunctiva at a position 1-2 mm posterior to the corneal scleral limbus. Each of three to four treatment spots was targeted to receive a thermal dose of 54 degrees C for 1 minute. Clinical, gross, and histopathological evaluations were performed. RESULTS--Clinical evaluations of the treatment sites (immediately after microwave application) revealed no evidence of conjunctival or scleral damage. Trace fluorescein 2% uptake was noted within the targeted zones. The first eye was sectioned along the equatorial axis. Examination of the ciliary body and pars plana revealed whitening of the ciliary processes and depigmentation. Histopathological evaluations revealed ciliary epithelial necrosis with pigment dispersion. The vascularity of the ciliary processes showed focal disruption and haemorrhage. The underlying ciliary muscle and sclera appeared to be unaffected. No other findings could be attributed to microwave cyclodestruction. CONCLUSION--The results of this phase I toxicity study suggest that microwave heating can be used to damage preferentially the epithelial layers of the human ciliary body.     

The effect of upper eyelid blepharoplasty on eyelid and brow position

This article evaluates the effect of upper eyelid blepharoplasty on eyelid margin position and brow height. This study is a retrospective analysis of patients who underwent upper eyelid blepharoplasty without concurrent blepharoptosis repair or brow surgery. The medical records of the participants were retrospectively reviewed and an established image analysis software was used to quantify the upper margin reflex distance (MRD1) as well as brow height using high quality standardized clinical photographs. A total of 19 patients (38 eyelids and brows) met the inclusion criteria. The mean preoperative MRD1 was 2.8 mm, and the mean post-operative MRD1 was 3.5 mm, revealing an increase of MRD1 from upper blepharoplasty alone of 0.7 mm (p = 0.0001). The mean preoperative brow position was 17.5 mm above the pupil, and the mean post-operative position was 17.4 mm, for an average change of position of -0.2 mm (p = 0.39) following upper eyelid blepharoplasty. Upper eyelid blepharoplasty without ptosis surgery results in a statistically significant increase in MRD1. Brow position does not demonstrate a statistically significant change in patients who undergo upper eyelid blepharoplasty for simple dermatochalasis.     

Ablation centration after active eye-tracker-assisted photorefractive keratectomy and laser in situ keratomileusis

PURPOSE: To evaluate the ablation centration after active eye-tracker-assisted photorefractive keratectomy (PRK) and laser in situ keratomileusis (LASIK) and to investigate the effect of surgery, patient, and surgeon on the centration. SETTING: Department of Ophthalmology, China Medical College Hospital, Taichung, Taiwan, Republic of China. METHODS: This retrospective study comprised 177 eyes of 101 patients: 16 eyes had PRK and 161, LASIK. All laser treatments were performed with the aid of an eye tracker. The amount of decentration was analyzed by corneal topography. The factors influencing centration were divided into surgery related (PRK/LASIK), patient related (low/high myopia and effect of learning), and surgeon related (learning curve). RESULTS: The mean decentration was 0.33 mm in PRK eyes and 0.35 mm in LASIK eyes. For the surgery-related factor, there was no significant difference between the PRK and LASIK eyes. For the patient-related factors, centration was better in the second eye (effect of learning) and decentration was more severe in eyes with high myopia (low/high myopia). For the surgeon-related factor, there was no significant difference between eyes that had the first 50 LASIK procedures and those that had the last 50 procedures. CONCLUSIONS: An eye tracker, which makes the laser beam follow the eye's movements, helps to avoid severe decentration. This study showed, however, that an active eye-tracking system alone cannot ensure good centration. Patient cooperation and fixation are important.     

前房深度对人工晶状体位置影响的研究

目的:探讨前房深度对人工晶状体位置的影响。方法:回顾性研究。收集广州爱尔眼科医院2018年1月至12月行飞秒激光辅助白内障超声乳化人工晶状体植入术119例(134眼)的临床资料。据术前前房深度,本组患者分成3组：浅前房组(A组),48例(55眼),前房深度<2.5 mm;正常前房深度组(B组),50例(52眼),前房深...     

Ultrasonographic study of the effect of different miotics on the eye components.

The effect of topical instillations of carbachol 3%, pilocarpine 2%, aceclidine 2%, aceclidine 2%-adrenaline 1%, and of the Ocusert delivery system was determined and compared in 151 eyes. The depth of the anterior chamber, the thickness and the position of the lens, the length of the vitreous and the refraction were studied. Aceclidine has negligible side effects on the ocular components (maximal change of the anterior chamber 0.20 mm; maximal change of the lens thickness 0.14 mm; maximal myopisation: -1.5 delta. Carbachol has the strongest side effects (maximal change of the anterior chamber 0.80 mm; maximal change of the lens thickness 0.80 mm; maximal myopisation -11.50 delta). Carbachol and pilocarpine may cause an important forward displacement of the lens with the risk of an angle-closure glaucoma in an eye with shallow anterior chamber.     

Postural change of intraocular and blood pressures in ocular hypertension and low tension glaucoma.

The effect of body position on the intraocular and blood pressures of normal volunteers and of patients with ocular hypertension and low tension glaucoma was studied. Changing from the sitting to the supine position increased the intraocular pressure by an average of 4.4 (SD 2.0) mm Hg in the control group, 4.0 (SD 2.0) mm Hg in the ocular hypertension group, and 4.1 (SD 1.8 mm Hg) in the low-tension glaucoma group. After 30 minutes in the supine position the intraocular pressure in normal volunteers and patients with low tension glaucoma remained stable. In contrast patients with ocular hypertension showed a further significant increase in intraocular pressure of 1.6 (SD 2.8) mm Hg (p = 0.004). This was accompanied by an equally significant decrease in blood pressure (p less than 0.001). We believe that these are manifestations of different mechanism of intraocular pressure regulation between these groups.