白内障术后人工晶状体混浊基础研究新进展

白内障术后人工晶状体混浊是近来研究的热点之一.不同材料的人工晶状体的混浊机制不同,亲水性丙烯酸酯和硅凝胶人工晶状体混浊多为沉积性混浊,而疏水性丙烯酸酯和PMMA人工晶状体混浊多为非沉积性混浊;沉积物除常见的羟基磷灰石外,还包括蛋白质、无机盐等多种类型;房水高钙磷学说和人工晶状体诱导学说均可能是导致人工晶状体混浊的发病机制;糖尿病和青光眼被认为是与人工晶状体混浊关系最大的两种疾病.     

白内障术后后囊膜混浊的发生因素

晶状体后囊膜混浊是白内障摘除联合后房型人工晶状体植入术后最常见的并发症,其发生率与人工晶状体的材料、镜片的式样,手术技术等因素均有关。新型的亲水丙烯酸和疏水丙烯酸AcrysofTM人工晶状体由于材料有良好的生物相容性及粘附性能,从而降低了后囊膜混浊的发生率。后凸型的人工晶状体、矩形锐利直角的光学边缘的人工晶状体、小切口白内障超声乳化摘除术、连续环形撕囊可以减少后囊膜混浊的发生率。     

超声乳化白内障吸除人工晶状体植入术后远期人工晶状体混浊的研究

目的　分析超声乳化白内障吸除人工晶状体植入术后远期亲水性丙烯酸酯折叠式人工晶状体光学部发生混浊、引起视力障碍行人工晶状体置换术的原因。方法　对 19例 (2 2只眼 )超声乳化白内障吸除人工晶状体植入术后远期亲水性丙烯酸酯折叠式人工晶状体光学部发生混浊的患者 ,行人工晶状体置换术。将取出的 2 2片混浊人工晶状体进行裂隙灯和光学显微镜检查 ;应用钙特异性茜素红染色法和vonKossa嗜银染色法进行病理学检查 ;使用扫描电镜观察沉淀物的位置和形态 ;应用能谱分析法检查沉淀物中的元素成分。以透明人工晶状体作为对照。结果　在人工晶状体光学部表面和表面下可见沉淀结晶呈多种形态的不规则颗粒 ,其中光学部中央着色颗粒密集且粗大 ,周边着色颗粒稀疏而细小。这些颗粒茜素红染色和vonKossa嗜银染色均为阳性反应。能谱分析证实颗粒中含钙和磷元素。人工晶状体襻和透明人工晶状体均无相同表现。结论　超声乳化白内障吸除人工晶状体植入术后远期 ,亲水性丙烯酸酯折叠式人工晶状体混浊的原因 ,为人工晶状体光学部表面和表面下发生钙和磷化合物沉淀结晶     

双眼人工晶状体混浊一例

80岁男性患者,双眼白内障术后18年,右眼瞳孔区人工晶状体光学部混浊致密,左眼人工晶状体光学部周边轮辐样混浊。行右眼人工晶状体置换术。取出的人工晶状体光学部为硅胶,周边部及襻为PMMA,光学部前后表面混浊,中间透明,襻及周边部透明。 （眼科,2020, 29： 399-400）     

超声乳化白内障吸除人工晶状体植入术后远期人工晶体状混浊的研究

目的：分析超声乳化白内障吸除人工晶状体植入术后远期亲水性丙烯酸酯折叠式人工晶体状光学部发生混浊、引起视力障碍行人工晶状体置换术的原因。方法：对19例（22只眼）超声乳化白内障吸除人工晶状体植入术后远期亲水性丙烯酸酯折叠式人工晶状体光学部发生混浊的患者，行人工晶状体置换术。将取出的22片混浊人工晶状体进行裂隙灯和光学显微镜检查；应用钙特异性苯素红染色法和von Kossa嗜银染色法进行病理学检查；使用扫描电镜观察沉淀物的位置和形态；应用能谱分析法检查沉淀物中的元素成分。以透明人工晶状体作为对照。结果：在人工晶状体光学部表面和表面下可见沉淀结晶呈多种形态的不规则颗粒，其中光学部中央着色颗粒密集且粗大，周边着色颗粒稀疏而细小。这些颗粒苯素红染色和von Kossa嗜银染色均为阳性反应。能谱分析证实颗粒中含钙和磷元素。人工晶状体襻和透明人工晶状体均无相同表现。结论：超声乳化白内障吸除人工晶状体植入术后远期，亲水性丙烯酸酯折叠式人工晶状体混浊的原因，为人工晶状体光学部表现和表面下发生钙和磷化合物沉淀结晶。     

人工晶状体材料的研究进展

随着白内障超声乳化吸除联合人工晶状体植入术的广泛应用，许多白内障患者都恢复了有效视力。术后人工晶状体混浊是评价生物相容性的重要指标，它会影响患者的视觉质量，不同材料人工晶状体混浊的表现及危险因素是不同的。然而，获得较好的视觉质量不是由单一因素决定的，人工晶状体的材料、患者对人工晶状体的反应等都是影响术后视觉质量的因素。随着科技的不断进步，越来越多的新材料在人工晶状体领域得到应用，充分了解不同人工晶状体材料的特性，为患者选择合适的人工晶状体，减少材料导致的并发症，将为患者带来福音。本文就不同人工晶状体材料的特性与人工晶状体植入术后发生混浊的表现及危险因素进行探讨。     

硅凝胶折叠人工晶状体术后混浊2例

随着白内障超声乳化吸出和人工晶状体植入术的广泛开展，国内外陆续报道了不同材料折叠人工晶状体术后混浊的病例。我院2004年至2005年共开展白内障超声乳化吸出和人工晶状体植入术共1000余例，发现人工晶状体术后混浊2例，现报告和分析如下。     

人工晶状体的自身特性与后囊膜混浊的关系

后囊膜混浊是白内障摘除联合后房型人工晶状体植入术后导致视力下降的最主要并发症之一。选择理想的人工晶状体可以明显降低后囊膜混浊的发生 ,本文就人工晶状体的材料、设计、光学直径大小等与后囊膜混浊的关系加以综述     

人工晶状体的自身特性与后囊膜混浊的关系

后囊膜混浊是白内障除联合后房型人工晶状体植入术后导致视力下降的最主要并发症之一。选择理想的人工晶状体可以明显降低后囊膜混浊的发生，本就人工晶状体的材料、设计、光学直径大小等与后囊膜混浊的关系加以综述。     

先天性无虹膜合并白内障的手术治疗进展

先天性无虹膜患者常伴有白内障,并可合并角膜混浊、青光眼、晶状体异位等其他眼部异常,是眼科治疗难点.目前,对于晶状体混浊达手术指征者,主要治疗方法为白内障摘除联合人工晶状体(intraocular lens,IOL)植入术;对于单纯性畏光、无明显晶状体混浊者,不建议手术治疗.常规折叠型IOL适用于2～6岁儿童,6岁以上患...     

超声乳化人工晶状体植入术后膜形成的分析

目的：探讨白内障超声乳化吸出及人工晶状体植入后人工晶状体前膜形成的机制和处理方法。方法：对393例进行术后随访观察。结果：有21眼人工晶状体前膜形成，发生率5．0％，用皮质类固醇治疗有效，1周内大部分吸收，无1例复发，有2眼用YAG，1眼失败，不影响术后矫正视力，结论：人工晶状体前膜是超声乳化及人工晶状体植入后常见早期并发症，其形成可能与血－房水屏障破坏和免疫反应有关，大多数病例通过药物治疗可完全吸收，视力增进。     

Subluxationsserie eines hydrophilen Kunstlinsentyps nach umkomplizierter Phakoemulsifikation

Background

As techniques for cataract surgery have evolved, spontaneous intraocular lens (IOL) dislocation in patients with no ocular pathology arises less frequently. We present seven consecutive cases of uncomplicated cataract surgery with early in-the-bag spontaneous intraocular lens dislocation for which the same type of hydrophilic single piece lens was used.

Material and methods

A retrospective analysis was conducted on seven cases involving patients with IOL dislocation who underwent uncomplicated cataract surgery within a period of 4 months (October 2010 to January 2011) using the same type of single piece IOL. The median age of the 7 patients was 73 years and IOL repositioning was performed after an average of 10 weeks.

Results

Sulcus repositioning could be carried out in only five of the seven patients and IOL repositioning within the capsule was achieved in one patient. A second patient exhibited IOL dislocation after yttrium aluminium garnet (YAG) laser capsulotomy. Explantation of the IOL and sulcus implantation of another IOL type (Acrysof MA50?MB) was necessary for a third patient. A fourth case presented an angled IOL haptic and dislocation of the IOL in the sulcus position.

Discussion

Even after uncomplicated cataract surgery, spontaneous in-the-bag IOL dislocation in patients with no ocular pathology may occur due to a hydrophilic lens material which induces stronger anterior capsular phimosis (ACP) in comparison to alternative materials. In combination with a thin lens design this may result in angled IOL haptics and IOL dislocation.

Conclusions

Careful selection of suitable lens design and material according to individual predisposing factors is necessary. This retrospective case study demonstrates that the combination of hydrophilic lens material and a thin lens design may result in early spontaneous IOL dislocation. Furthermore, as established in one case, YAG laser capsulotomy may induce IOL dislocation if the lens design cannot withstand capsular fibrosis.     

无晶状体眼屈光矫治方法的概述

无晶状体眼的屈光矫治方法包括框架眼镜矫正、角膜接触镜矫正和人工晶状体(IOL)植入术.框架眼镜矫正物像放大率高,视野受限,婴幼儿无晶状体眼因眼球尚处在发育阶段致无法植入人工晶状体而多选用框架眼镜矫正.角膜接触镜物像放大率低,分为软性角膜接触镜和硬性角膜接触镜,前者因透氧性差易致眼表病变故应用较少,后者透氧性强,尤适合于眼外伤所致不规则散光者或虹膜缺失者.目前临床上最常用的还是人工晶状体植入术,植入人工晶状体的眼更符合生理解剖结构,可以尽量避免屈光参差、像差等不足.根据人工晶状体的植入位置共分为前房型人工晶状体植入术和后房型人工晶状体植入术,前房型人工晶状体植入术又分为房角固定型人工晶状体植入术和虹膜固定型人工晶状体植入术,后房型人工晶状体植入术分为Ⅱ期囊袋内人工晶状体植入术、睫状沟人工晶状体植入术和经巩膜缝线式人工晶状体植入术.     

超声乳化联合IOL植入治疗晶状体溶解性青光眼的临床研究

目的:研究超声乳化联合人工晶状体植入治疗晶状体溶解性青光眼的治疗效果。方法:对32例32眼过熟期白内障继发晶状体溶解性青光眼患者,采用超声乳化联合人工晶状体植入给予治疗,对视力及眼压情况进行观察和研究。结果:术后随访0.5a,眼压均控制到正常范围内,视力有不同程度提高。结论:通过临床观察证明单纯超声乳化联合人工晶状体植入治疗晶状体溶解性青光眼安全有效,且手术切口小,组织损伤小,术后反应较轻,可有效控制眼压,恢复视功能。     

In-the-bag secondary intraocular lens implantation in children

BACKGROUND: Surgery for congenital cataracts in early infancy usually includes a primary posterior capsulectomy and an anterior vitrectomy. Initially, most of these infants have aphakia after surgery. Over time, remaining equatorial lens epithelial cells produce new cortical fibers, resulting in a ring of cortex trapped between the lens equator and the fused anterior and posterior capsulectomy edges. A potential space is maintained between the anterior and posterior capsular leaflets. We describe a technique for placing a secondary intraocular lens (IOL) within the capsular bag. PATIENTS AND METHODS: Eight children, ranging in age from 11 months to 14 years, who originally had aphakia after cataract extraction were operated on with the intent to reopen the capsular bag and place an IOL in the bag. RESULTS: Secondary in-the-bag IOL implantation was successfully completed in 7 of 8 children. This was accomplished by reopening the capsular bag 360 degrees at the edge of the fused anterior and posterior capsulectomy remnants, using the previously published vitrectorhexis technique. Residual cortical material was aspirated, and an IOL was placed within the capsular bag. In 1 child, aged 14 years, the capsular bag was reopened, but the lens was placed in the ciliary sulcus because the new anterior capsule edge could not be visualized for 360 degrees . CONCLUSION: Placement of secondary IOLs within the capsular bag can be accomplished successfully for selected patients in the pediatric population. Surgeons operating on infantile cataracts without primary IOL placement can facilitate capsular IOL sequestration later by limiting the anterior and posterior capsulectomy to 4 to 5 mm and performing a generous anterior vitrectomy to help prevent secondary closure of the smaller capsulectomy.     

Intraocular lens power calculation. A retrospective analysis of its practical value

Two hundred and two consecutive intraocular lens (IOL) implantations, the lens power being predicted with the SRK-method, are retrospectively analyzed, and the factors possibly influencing the error in IOL power prediction are evaluated. The actual post-operative refraction is compared to the expected refraction for each IOL and to a hypothetical refraction that would have been obtained by a standard-power IOL implant. Axial length measurement and a high pre- and post-operative astigmatic error, along with low- and high power IOL predictions, are the factors that most influence the post-operative refractive error. A similar distribution of post-operative refraction could have been obtained by using a standard-power IOL instead of pre-operative calculation.     

Artisan aphakic intraocular lens in children with subluxated crystalline lenses

PURPOSE: To evaluate the results of Artisan (Ophtec) aphakic intraocular lens (IOL) implantation in children with idiopathic subluxated lenses. SETTING: Department of Ophthalmology, Soroka University Medical Center, Beer-Sheva, Israel. METHODS: This retrospective small case series comprised 4 eyes (3 children) with idiopathic essential subluxated lenses that had lens washout, lens capsule removal, Artisan IOL implantation, and peripheral iridectomy. The indications for surgery were reduced visual acuity and monocular diplopia. The main outcome measures were postoperative refraction and change in best corrected visual acuity (BCVA). RESULTS: The postoperative follow-up ranged from 8 to 10 months. After surgery, the BCVA was 6/12 or better in the 3 cases that could be recorded. Visual acuity improved by 2 or more Snellen lines in all 4 eyes. The postoperative spherical equivalent was within +/-1.00 diopter in all cases. No significant postoperative complications were observed. CONCLUSIONS: In 4 eyes with a subluxated crystalline lens, implantation of an Artisan aphakic IOL improved visual acuity. Studies with a larger number of patients and longer follow-up are necessary to confirm these results.     

儿童外伤性白内障人工晶状体固定性瞳孔夹持的原因与手术治疗

目的 回顾性分析儿童外伤性白内障摘除术后人工晶状体(IOL)固定性瞳孔夹持的原因,并探讨有效的治疗方法.方法 对14岁以下外伤性白内障的患者行白内障摘除后房犁人工晶状体植人术后固定性瞳孔夹持患者10例(10只眼),分析其发生原因及并发症,并行虹膜粘连分离,后发性白内障切除,人工晶状体复位术及前段玻璃体切割术.5只眼行IOL置换术.结果 10只眼成功完成分离虹膜与囊膜粘连并行后发性白内障切除和人工晶状体复位,术后视功能不同程度的改善.结论 外伤性白内障术后葡萄膜炎反应,瞳孔粘连,后发性白内障及周边皮质再生是引起儿童IOL固定性瞳孔夹持的重要原因.手术分离虹膜粘连、清除晶状体再生皮质并切除后发性白内障可有效复位IOL.     

Optical analysis of an accommodating intraocular lens

PURPOSE: To model the feasibility of an accommodating intraocular lens (IOL) that allows near vision by means of an anterior translation within the capsular bag. SETTING: University of Waterloo, Waterloo, Ontario, Canada. METHODS: Model eyes were constructed and analyzed based on experimental data using Code V, a computerized optical design tool. The potential near vision of IOLs of different powers was calculated as they were moved anteriorly within the capsular bag. The conditions under which a spherical lens performs well and when an aspheric design should be considered were determined. RESULTS: Accommodation (the dioptric change from the far to the near point) varies linearly with lens movement and is sensitive to corneal and IOL powers. Simple equations were derived and accurately predicted induced accommodation. Retinal image quality varies significantly with pupil size and IOL power. However, image quality is minimally affected by the amount of induced accommodation. CONCLUSIONS: From an optical standpoint accommodation with adequate image quality can be achieved by anterior movement of a spherical IOL within the capsular bag.     

Feasibility of multifocal intra‐ocular lens exchange and conversion to the bag‐in‐the‐lens implantation

Purpose: Our purpose was to evaluate the surgical outcome after intra‐ocular lens exchange in patients who presented impairing visual complaints after primary multifocal intra‐ocular lens (MIOL) implantation. In particular, the study was undertaken to look at the number of eyes that could be equipped with the bag‐in‐the‐lens (BIL) IOL after MIOL exchange. Methods: This series consisted of 30 eyes of 21 consecutive patients scheduled for MIOL exchange. In 15 out of the 30 eyes, IOL misalignment was measured on slit lamp anterior segment photo’s after defining the mathematical centres of the IOL optic, pupil and limbus. Results: Diffractive MIOL was more frequently explanted (25; 83%) when compared with refractive MIOL (4; 13%) and progressive optic IOL (1; 4%). In 21 out of the 30 eyes (70%) a bag‐in‐the‐lens could be implanted. In 7 out of the 30 eyes (23%), the capsule was not considered sufficiently stable to accommodate an IOL. An iris‐fixated IOL or a sulcus‐fixated IOL was then implanted. In 2 out of the 30 eyes (6%) the remaining capsular bag could accommodate a traditional lens‐in‐the‐bag only. Eyes that underwent Nd:YAG laser capsulotomy prior to the MIOL exchange needed anterior vitrectomy peroperatively (11 eyes; 37%). Visual acuity improved postoperatively in 13 out of the 30 eyes and remained stable in 17 out of the 30 eyes. Conclusions: Since the BIL technique requires a very well‐preserved capsular bag for the purpose of the IOL implantation, the success rate of BIL implantation after MIOL is a good indicator to evaluate the degree of difficulty to exchange MIOL.