A dual optic accommodating foldable intraocular lens

AIM: To design an accommodating intraocular lens with extended accommodative range that can be adapted to current standard phacoemulsification and endocapsular implantation technique. METHOD: Ray tracing analysis and lens design; cadaver eye implantation. RESULTS: Ray tracing analysis indicated that axial movement of an exaggerated converging anterior optic linked by spring loaded haptics to a compensatory static diverging posterior optic produced greater change in conjugation power of the eye compared to axial movement of a single optic lens. A dual optic one piece foldable silicone lens was constructed and implanted via a 4 mm corneal incision into the capsular bag of two cadaver eyes. CONCLUSION: A dual optic intraocular lens design can increase the optical effect of a given displacement and suggests improvements for accommodating intraocular lenses.     

Pseudophakic accommodation with translation lenses – dual optic vs mono optic

PURPOSE: To investigate the pseudophakic accommodation effect in dual and mono optic translation accommodative intraocular lenses (AIOL) using linear matrix methods in the paraxial space. METHODS: Dual (anterior optic of power +32 D linked to a compensatory posterior optic of negative power) and mono lens power was determined in the non-accommodated state using linear geometric optics based on the Gullstrand model eye. The position of the AIOL was calculated from a regression formula. Pseudophakic accommodation was assessed with three systems: (1) forward shift of the mono optic lens, (2) anterior translation of the anterior optic in the dual optic lens system with an unchanged position of the posterior minus lens and (3) symmetrical anterior and posterior translation of the anterior and posterior lens. The Gullstrand model eye was modified by changing the axial length (and proportionally changing the phakic anterior chamber depth) to investigate the accommodative effect in myopic and hyperopic eyes. RESULTS: The dual optic lens system (2) yields a nearly constant accommodation amplitude of 2.4-2.5 D mm(-1) movement over the total range of axial lengths. The mono optic lens (1) provides a higher accommodative effect only in extremely short eyes (high refractive power of the lens), whereas for normal eyes (1.4-1.5 D mm(-1) movement) and for long (myopic) eyes the accommodative effect is much less than the dual optic lens. The dual optic lens system under condition (3) yields less accommodation amplitude compared with the dual optic system under condition (2) over the total range of axial length but provides higher accommodation amplitude compared with the mono optic lens system (1) with axial lengths greater than 22.3 mm (lens power 25.5 D). In the accommodated state, with lens translation of 1 mm, the absolute value of the lateral magnification increases with the refractive power of the mono optic lens (1) and decreases in both dual optic lens systems (under conditions 2 and 3). CONCLUSIONS: A mathematical strategy is presented for calculation of the accommodative effect of mono-optic and dual optic AIOL. The dual optic lens yielded a nearly constant accommodation amplitude of about 2.4-2.5 D mm(-1) translation, whereas the mono optic lens yielded an accommodative response of <2 D mm(-1) translation in long myopic or normal eyes. Only in extremely short eyes is the accommodative amplitude of the mono-optic lens higher than the dual optic lens.     

Accommodative intraocular lenses: current status

PURPOSE OF REVIEW: The possibility of using a monofocal IOL with accommodative ability allows refractive cataract surgery with a clearly decreased potential of photic phenomena. Three IOLs of different designs and materials have demonstrated accommodative ability, but the degree of accommodative amplitude has been reported to different extents and variabilities. The plate-haptic CrystaLens has a hinged design that might permit forward movement of the optic as a result of pressure changes in the vitreous cavity. The 1CU has modified haptics that bend in the bag as the lens capsule contracts, which are supposed to cause anterior displacement of the lens optic. With the dual-optic one-piece Synchrony, springlike haptics separate a high-plus anterior lens from a posterior minus lens. With accommodative effort, the capsular bag expands and the springs express kinetic energy, which might allow the optics to separate as the anterior lens moves forward. RECENT FINDINGS: This article seeks to clarify and distinguish the concepts of true accommodation and pseudo accommodation. Current designs of accommodative IOLs are supposed to work by the focus-shift principle to allow true pseudophakic accommodation. Studies that biometrically assessed optic shift found no or only low amplitudes of forward movement. The amount of forward movement, if present, was highly variable between patients. To date, most studies present psychophysical data for the proof of concept, which alone seems insufficient. Capsule bag performance and posterior capsule opacification with accommodative IOLs seem worse than those with standard intraocular lenses. SUMMARY: The potential clinical benefits of accommodative IOL technology for both cataract patients and refractive patients may place accommodative IOLs in a competitive position with multifocal IOL technology.     

Magnification changes in scanning laser tomography

PURPOSE: It is important when evaluating glaucomatous optic disc progression in longitudinal images that image magnification remains unchanged. We studied the effect of changed lens power on magnification in scanning laser tomography. The relative contribution to magnification of axial length, eye-scanner distance, and image-to-image scaling was also assessed. METHODS: A simulated optic disc in a model eye was imaged using the Heidelberg Retina Tomograph. Lens power was alterable by exchanging intraocular lenses (IOL) mounted at the lens plane of the eye to mimic changes in the crystalline lens. IOL power of +20.0D and axial length of 21.5 mm was compatible with emmetropia. The optic disc was imaged through IOLs differing in power (+16.0D to +25.0D) but with axial length kept constant. IOL power was then held constant and imaging was repeated for various axial lengths (17.5-23.5 mm). Model eye-scanner distance was varied with each test sequence. The distances between landmarks on the disc was measured before and after contour lines were exported. RESULTS: Image size varied with IOL power and axial length (r > 0.98; P < 0.0001), with the magnification effect of a +1D increase in lens power equivalent to a third the magnification effect of a 1-mm increase in axial length. Magnification tended to increase with myopia (IOL power > +20.0D) and was accentuated by longer eye-scanner distances. Image-to-image scaling corrected some magnification though this varied with ametropia. CONCLUSIONS: Changed lens power, axial length, and eye-scanner distance can affect the size of the optic disc in scanning laser tomography images. The exported contour line partly compensates for changed magnification.     

双元件可调节人工晶状体设计

目的：设计一种新的双元件可调节人工晶状体,并对其成像质量进行评估。方法：通过光学设计软 件Zemax,建立新设计的双元件可调节人工晶状体和人眼模型,模拟仿真其在不同视距下（L=6 m、 L=70 cm、L=40 cm以及L=25 cm）的成像结果,得到空间频率为100 cycles/mm时的调制传递函数 （MTF）值。与Simonov等研究结果进行对比分析,同时分析仿真结果是否满足人工晶状体植入光学 特性和测试标准。结果：通过光学设计软件模拟仿真新设计的双元件可调节人工晶状体眼模型,其 结果显示无论α=0°还是α=5°,瞳孔大小为3 mm时,单色光（λ=0.546 μm）空间频率100 cycles/mm 对应的MTF值均大于0.43,满足人工晶状体植入光学特性和测试标准。在α=0°时,仿真结果相较 于Simonov等研究结果有较大提升;在α=5°时,无明显提升。结论：本研究设计的双元件可调节人 工晶状体仿真结果满足人工晶状体植入光学特性和测试标准要求,相较于Simonov的研究结果,其 整体性能有所提升。     

双光可调节型人工晶状体眼调节幅度的计算及影响因素

目的 推导计算双光可调节型人工晶状体(DO-AIOL)植入术后眼调节幅度(AA)的数学公式,分析影响人工晶状体眼AA的相关因素.方法 根据高斯近轴光学理论推导得出计算AA的数学计算公式,以眼轴长(AL)、角膜屈光力(K)、DO-AIOL两个光学部的屈光力(IOL1IMP,IOL2IMP)、人工晶状体(IOL)的有效位置(ELP)、IOL光学部的移动量(ΔELP)、DO-AIOL两个光学部的距离(d)、DO-AIOL两个光学部距离的变化量(Δd)计算AA,分析以上各参数对AA的影响.结果 双光可调节IOL眼AA与AL、IOL2IMP及两个光学部的距离不相关.在IOL1IMP=32 D,ELP=4 mm,ΔELP=1 mm,Δd=1 mm时,DO-AIOL可为任意眼轴长患者提供的AA为2.49 D.AA为IOL1IMP的二次函数,AA随IOL1IMP的增大而增大,表明通过增大IOL1IMP可获得较大的AA.AA为K的二次函数,AA随角膜屈光力的增大而增大.AA与ELP呈负相关,与ΔELP、Δd呈正相关,与两个光学部的距离无关,对于DO-AIOL设计的改进具有指导意义.结论 研究推导得出计算双光可调节IOL眼的AA的数学公式,AA受IOL1IMP、K、ELP、ΔELP、Δd等多因素影响,不受AL影响.     

Cardinal points and image–object magnification with an accommodative lens implant (1 CU)

A simple mathematical method for the determination of the cardinal points of pseudophakic eyes after implantation of an accommodative intraocular lens [posterior chamber intraocular lenses (PCIOL)] is presented. The purpose of this study was to explore the changes during pseudophakic accommodation (PAC) in (1). the positions of the cardinal points, (2). the distance of the object conjugate with the retina, and (3). the image-object magnification. These theoretical accommodation data are compared with clinical measurements. METHODS AND PATIENTS: Using biometrical measurements of the axial length, equivalent power of the cornea and the anterior chamber depth (ACD) in the non-accommodated state we used linear geometric optics for determination of the cardinal points and object distance as well as lateral magnification (the ratio of image to object size). With the measurement of ACD decrease (following pharmacological stimulation of the ciliary muscle with 2% pilocarpine eye drops) we determined the changes of the cardinal points and magnification to assess PAC amplitude from the shortening of the object distance. Calculated values of PAC amplitude were compared with the respective measured values derived from amplitude measures by accommodometer, defocusing and streak retinoscopy. We analysed the results of a prospective study on 35 eyes of 28 patients after cataract surgery (target refraction: -0.2 D) and accommodative PCIOL implantation (1 CU, Human Optics AG, Erlangen, Germany) 3 months after surgery. RESULTS: After pilocarpine eye drops, ACD (mean +/- S.D., range; median) decreased by 0.88 +/- 0.48 mm (0.51-1.91; 0.66). Distance of the in-focus object decreased from the non-accommodated state (-5.62 +/- 1.83 m, -25 to -1.1; -4.83 m) to the accommodated state (ACD decrease) (-0.81 +/- 0.21, -2.11 to -0.65; -0.79 m). For a theoretical ACD decrease of 1.0 mm (the intrinsic limitation of the PCIOL design) it was -0.59 +/- 0.28, -1.31 to -0.51; -0.63 m and resulted in an objective accommodative response of 1.49 +/- 0.16, 1.21-1.81; 1.46 D, depending on the actual geometry of the individual eye. On average, magnification as induced by PAC in contrast to that induced by adequate spectacle addition differed by only about 1%. Accommodation measured with defocusing and the accommodometer correlated significantly with the theoretical value based on IOLMaster measurement of ACD decrease (r = 0.752, p = 0.005 and r = 0.676, p = 0.02). Likewise, accommodation measured with streak retinoscopy correlated weakly with the theoretical value based on IOLMaster ACD decrease (r = 0.465, p = 0.05). CONCLUSIONS: Using geometrical optics, PAC can be derived from the biometric data of the eye and the measured ACD decrease. This approach may be an additional indicator for the accommodative response in pseudophakic patients and may allow a subdivision of the measured accommodation into true PAC and pseudoaccommodation, for example, because of increased depth of focus induced by pupillary constriction.     

Image quality in polypseudophakia for extremely short eyes

AIM: To evaluate the image quality produced by polypseudophakia used for strongly hypermetropic and nanophthalmic eyes. METHODS: Primary aberration theory and ray tracing analysis were used to calculate the optimum lens shapes and power distribution between the two intraocular lenses for two example eyes: one a strongly hypermetropic eye, the other a nanophthalmic eye. Spherical aberration and oblique astigmatism were considered. Modulation transfer function (MTF) curves were computed using commercial optical design software (Sigma 2100, Kidger Optics Ltd) to assess axial image quality, and the sagittal and tangential image surfaces were computed to study image quality across the field. RESULTS: A significant improvement in the axial MTF was found for the eyes with double implants. However, results indicate that this may be realised as a better contrast sensitivity in the low to mid spatial frequency range rather than as a better Snellen acuity. The optimum lens shapes for minimum spherical aberration (best axial image quality) were approximately convex-plano for both lenses with the convex surface facing the cornea. Conversely, the optimum lens shapes for zero oblique astigmatism were strongly meniscus with the anterior surface concave. Correction of oblique astigmatism was only achieved with a loss in axial performance. CONCLUSIONS: Optimum estimated visual acuity exceeds 6/5 in both the hypermetropic and the nanophthalmic eyes studied (pupil size of 4 mm) with polypseudophakic correction. These results can be attained using convex-plano or biconvex lenses with the most convex surface facing the cornea. If the posterior surface of the posterior intraocular lens is convex, as is commonly used to help prevent migration of lens epithelial cells causing posterior capsular opacification (PCO), then it is still possible to achieve 6/4.5 in the hypermetropic eye and 6/5.3 in the nanophthalmic eye provided the anterior intraocular lens has an approximately convex-plano shape with the convex surface anterior. It was therefore concluded that consideration of optical image quality does not demand that additional intraocular lens shapes need to be manufactured for polypseudophakic correction of extremely short eyes and that implanting the posterior intraocular lens in the conventional orientation to help prevent PCO does not necessarily limit estimated visual acuity.     

可调节型人工晶状体眼调节幅度的计算及其影响因素分析

目的①推导出计算可调节型人工晶状体(accom-modative intraocular lens,AIOL)植入术后眼的调节幅度(ac-commodative amplitude,AA)的数学公式。②探讨影响人工晶状体眼AA的相关因素,为研究AIOL植入手术的治疗效果提供理论依据。方法根据高斯近轴光线光学理论推导得出计算AIOL植入眼AA的理论计算公式,以人工晶状体(in-traocular lens,IOL)焦点的移动量(effective intraocular lensposition,ΔELP)、眼轴长(axial length,AL)、角膜屈光力(corneal power,K)、IOL的有效位置(effective lens position,ELP)、植入IOL的屈光力(power of the implanted IOL,IOLImp)计算AA,分别建立AA与ΔELP、AL、K、ELP、IOLImp的函数关系,分析以上各参数对AA的影响。结果①人工晶状体眼AA受ΔELP、AL、K、ELP、IOLImp的影响(AL=23.65mm、K=43.8D、ELP=5.8mm),屈光状态为正视、ΔELP...     

Magnification characteristic of a +90-diopter double-aspheric fundus examination lens

PURPOSE: To investigate the magnification characteristic of the +90-D double-aspheric fundus examination lens for biomicroscopic measurement of the optic disc. METHODS: A calibrated Gullstrand-type model eye adjusted for axial ametropia between -12.5 and +12.6 D was used to measure the change in magnification of the system with refractive error and variation in fundus lens position. A correction factor p (in degrees per millimeter) at different axial ametropias was also calculated. RESULTS: The total change in magnification of the system from myopia to hyperopia was -15.1% to +13.7%. When the fundus lens position was altered with respect to the model eye by +/-2 mm under myopic conditions, the change in magnification of the system was -4.8% to +8.1%. In the hyperopic condition the change was -4.8% to +6.0%. The fundus lens exhibited a linear relationship between p and the degree of ametropia of the model eye and a constant relationship between p and ametropia of -5 to +5 D. CONCLUSIONS: Axial ametropia has a significant effect on biomicroscopic measurement of the optic disc with the +90-D lens. Therefore, a correction factor (p) was calculated that can be used in calculations for determining true optic disc size. These findings may be important for improving clinical disc biometry.     

Miyake-Apple video analysis of movement patterns of an accommodative intraocular lens implant

BACKGROUND: The potentially accommodative intraocular lens (IOL) is a new development in IOL design METHODS: We evaluated the new Humanoptics 1CU accommodative IOL in a laboratory study with human post mortem autopsy eyes. Using the Miyake-Apple posterior view video technique, the movement pattern of the IOL was tested and observed from the posterior perspective. RESULTS. A circular bend at the level of the ciliary body applied slight circular force onto the sclera allowing the relaxation of the zonules. The shift of focus was demonstrated by using a reading target. In addition, viscoelastic was injected into the vitreous resulting in the same anterior movement of the IOL optic. CONCLUSIONS: The 1CU Humanoptics accommodative IOL showed potential accommodative behaviour in the laboratory. The accommodative (respectively pseudoaccommodative) effect was based on the anterior shift principle with anterior movement of the IOL-optic in the state of relaxing zonules. Whether this reflects the clinical situation, especially to this extent, must be further evaluated.     

Effect of the optic size of a single-piece acrylic intraocular lens on posterior capsule opacification

PURPOSE: To investigate the effect of the optic size of an intraocular lens (IOL) with sharp optic edges on posterior capsule opacification (PCO). SETTING: Nishi Eye Hospital, Osaka, Japan. METHODS: In 5 rabbits, a single-piece 5.5 mm optic AcrySof IOL (Alcon Laboratories) was implanted in 1 eye and a specially fabricated single-piece 7.0 mm optic AcrySof IOL was implanted in the contralateral eye. Histopathological examinations were performed 3 weeks after surgery. RESULTS: On posterior views, less PCO was noted with the 5.5 mm optic in all rabbits except 1. Histopathological sections demonstrated adhesion of the anterior and posterior capsules between the haptic and optic and the formation of a sharp capsular bend at the posterior optic edge in 3 eyes with the 5.5 mm optic but in no eye with the 7.0 mm optic. Abundant PCO was noted when a sharp capsular bend had not formed. CONCLUSIONS: Capsular adhesion is a prerequisite of capsular-bend formation. The sharp optic edge alone does not provide a substantial barrier when a capsular bend is not formed. Bulky haptics such as those of the single-piece AcrySof and large optics may hamper capsular adhesion and bend formation.     

Magnification characteristics of the Optical Coherence Tomograph STRATUS OCT 3000

PURPOSE: To evaluate the magnification characteristics of an Optical Coherence Tomograph (STRATUS OCT 3000) used to measure optic disc size. METHODS: An eye model was designed, built and used to measure changes in the magnification of the Optical Coherence Tomograph (OCT) with variation in the axial length of the eye and OCT correction lenses. Theoretical calculations using ray-tracing were used to compare the experimental and theoretical results. RESULTS: OCT-performed fundus measurements have a magnification that depends on two factors: eye axial length and optical correction with the focusing dial of the OCT. Theoretical calculations showed that the size of the optic disc image for greater axial lengths of the eye model (myopic eye) was less than that for smaller axial lengths (hyperopic eye). The disc diameter measurements of the image obtained with the OCT did not agree with the real disc size. By focussing with the focusing dial of the OCT, the power of the optics can be varied from -12.0 D to +12.0 D and the image size is decreased for all axial lengths. The maximum variation of the disc area was 2.1%. Differences in area measured at intervals of 2.0 D after correcting the eye refraction for measurements with the OCT were equivalent to the repeatability error at that point. CONCLUSIONS: Our results confirm that any variation in the optical system of the eye, in the OCT, and/or in the distance between them, induces a change in the magnification of the tomograph images. These variations will affect the measurements of any of the structures in the retinal plane.     

Optical analysis to predict outcomes after implantation of a double intraocular lens magnification device

PURPOSE: To analyze the effect of different optical parameters of the eye on the outcomes of implantation of a double intraocular lens (IOL) magnification device in patients with low vision. SETTING: Fundación Oftalmológica del Mediterráneo, Valencia, Spain. METHODS: The eye's refraction and magnification before and after surgery were evaluated using a theoretical eye model based on paraxial optics approximation. Four parameters on which refraction and magnification are dependent were evaluated: anterior chamber depth (ACD), axial length (AL), mean keratometry (Km), and the distance between the 2 implanted IOLs. The 4 variables were analyzed separately in the first stage. Next, different combinations of ACD, AL, and Km values were studied. The goal was to predict what type of eye (in terms of ACD, AL, and Km values) is suitable for successful implantation of the double-IOL magnification device. RESULTS: Axial length had a significant influence on eye magnification. The Km value mainly affected refraction. The ACD did not influence the success of the procedure. The distance between the 2 IOLs was a decisive parameter in the analysis. CONCLUSIONS: Analysis of optical and biometric eye parameters could guide selection of patients for implantation of the double-IOL magnification device. Eyes with higher AL and Km values (myopic eyes) are the most suitable for this procedure.     

Long-term effect of optic edge design in an acrylic intraocular lens on posterior capsule opacification

PURPOSE: To compare the posterior capsule opacification (PCO) inhibiting effect of the sharp posterior optic edge design of the Sensar OptiEdge AR40e intraocular lens (IOL) with that of the double-round edge design of the Sensar AR40 IOL over a period of 3 years. SETTING: Department of Ophthalmology, Medical University of Vienna, Vienna, Austria. METHODS: Fifty-three patients with bilateral age-related cataract (106 eyes) were included in this randomized prospective bilateral patient- and examiner-masked clinical trial with intraindividual comparison. Each study patient had cataract surgery in both eyes and received a Sensar AR40 IOL (anterior and posterior round optic edges) in 1 eye and a Sensar OptiEdge AR40e IOL (round anterior and sharp posterior optic edge) in the other eye. Follow-up examinations were at 1 week, 1 and 6 months, and 1, 2, and 3 years. Digital retroillumination images were taken of each eye. The amount of PCO was assessed subjectively at the slitlamp and objectively using automated image-analysis software (AQUA) 1, 2, and 3 years after surgery. RESULTS: The sharp-edged AR40e lens showed significantly less regeneratory and fibrotic PCO 1, 2, and 3 years after surgery. The mean AQUA PCO score was 2.18 for the AR40 and 1.00 for the AR40e lens after 1 year; 2.94 and 1.56 after 2 years, and estimated at 3.13 and 1.77, respectively, after 3 years (scale 0 to 10; P<.001). The neodymium:YAG laser capsulotomy rate was significantly higher in the AR40 group. The AR40e lens also led to less peripheral fibrotic PCO. There was no significant difference in complaints concerning edge glare between the groups. CONCLUSION: Compared with the AR40 IOL, the sharp posterior optic edge design of the Sensar OptiEdge AR40e IOL led to significantly less PCO 1, 2, and 3 years postoperatively. In contrast with most past studies on PCO-preventative factors, this study varied only 1 parameter, namely the optic edge design, and the main outcome measure (PCO) was assessed with an objective image-analysis system.     

Contrast and glare sensitivity after implantation of AcrySof and Human Optics 1CU intraocular lenses

PURPOSE: To evaluate contrast and glare sensitivity of a newly developed, potentially accommodative intraocular lens. METHODS: The clinical interventional prospective randomized study included 20 patients (23 eyes) undergoing standard phacoemulsification with clear cornea incision in topical anesthesia. In the study group (10 eyes), the 1CU Human Optics intraocular lens (optics diameter 5.5 mm) was implanted. The control group (13 eyes) received the monofocal AcrySof intraocular lens (optics diameter: 6.0 mm). Using a newly developed contrast measuring device, contrast and glare sensitivity were tested 4 weeks after surgery. RESULTS: The study group and control group did not vary significantly in contrast (p=0.38) or glare sensitivity (p=0.52). CONCLUSIONS: The results suggest that the newly developed 1CU Human Optics intraocular lens and the standard AcrySof intraocular lens do not vary significantly in glare and contrast sensitivity.     

Ultrasound measures of vitreous chamber depth during ocular accommodation

The vitreous chamber decreased in depth about 0.12 mm as accommodative demand increased from 0.2 to 7 D in nine accommodative steps. The depth decreases matched movement of the posterior lens surface toward the retina. Accommodation caused no significant increases in axial length compared to cyclopleged controls. These results do not favor the active role for the vitreous in accommodation proposed by Coleman in 1970. Computer analysis of A-scan interval counts demonstrated that multiple retinal complex peaks might erroneously point to vitreous or axial lengthening. About 30% of total lens thickening during accommodation was accounted for by posterior lens surface displacement.     

Status of accommodative intraocular lenses

PURPOSE OF REVIEW: This review examines the recent peer-reviewed literature of the past 18 months, with the goal of providing an overview of the pseudophakic lenses designed to provide accommodative action. Accommodative lenses take advantage of axial movement, refractive change and bag filling to provide their effect. Single and dual optic design, as well as unique technologies, were reviewed. RECENT FINDINGS: An overview is presented of the various accommodative lenses available for investigation and use. There is positive evidence that current accommodative intraocular lenses provide superior potential for near vision compared with standard intraocular lenses. SUMMARY: The available data suggest that accommodative amplitude and pseudoaccommodation are both important factors in the functional ability of accommodative intraocular lenses to provide a range of distance, intermediate and near vision.     

人工晶状体光学部囊袋后嵌入治疗儿童先天性白内障

目的 评价人工晶状体（IOL）囊上植入、光学部囊袋后嵌入治疗儿童白内障的临床效果。设计 回顾性病例系列。研究对象 15例（17眼）儿童先天性白内障患者。方法 超声乳化白内障吸除后，后囊连续环形撕囊，直径约4mm，将IOL光学部嵌于后囊后，襻位于囊袋上，使囊袋闭锁。主要指标裸眼视力、眼压、IOL位置及并发症。结果 术中17眼按设计的手术方式顺利完成。术后6个月5眼IOL位置从囊袋后向前移位至囊袋前，这其中有4眼发生视轴区混浊，余13眼在随访期间均未出现视轴区混浊。术后6个月的主要并发症为IOL表面沉着物：1级3眼（18％），2级7眼（41％）。虹膜前粘连1眼（6％），后粘连4眼（24％）。瞳孔变形5眼（29％）。结论 应用囊上植入、光学部囊袋后嵌入IOL治疗儿童白内障安全有效，可有效预防后发性白内障的发生。     

Accommodative intraocular lenses: considerations on use, function and design

PURPOSE OF REVIEW: To review the development, design and clinical implications of the first US Food and Drugs Administration approved accommodative lens. To inform the reader of forthcoming accommodative intraocular lens technologies that are being clinically tested and other technologies that are under design. RECENT FINDINGS: We present clinical data that are currently available or pending release on accommodative intraocular lenses. As much as the results of the technology can be appreciated, the approach toward the refractive mindset of the presbyopic intraocular lens patient must be understood and mastered. SUMMARY: Accommodative intraocular lens design and development are at a feverish pace. The lure is the perceived holy grail for the solution of presbyopia.