6种人工晶状体调制传递函数的研究

目的：研究人工晶状体的最佳光学结构，为人工晶状体的设计提供理论依据。方法：以Gullstrand Ⅰ号模型眼为基础，计算6种不同光学结构人工晶状体植入后的调制传递函数(MTF)。结果：6种不同光学结构人工晶状体植入后的MTF有明显差异。结论：一些特定结构的人工晶状体具有较好的成像质量，其中以双凸结构为最佳。     

基于SRK-T公式的人工晶状体A常数对白内障术眼像质的影响

目的研究采用SRK-T公式预算人工晶状体屈光度的人工晶状体A常数对人眼成像质量的影响。方法基于Gullstrand-Le Grand和Hwey-Lan Liou眼模型,利用ZEMAX光学设计软件实现光线追迹的方法模拟分了不同人工晶状体A常数情况下,以人眼光学系统的光学调制传递函数(MTF)表征植入相应屈光度的等双凸和凸平型球面工晶状体的术眼成像质量。结果当人工晶状体按照SRK-T公式计算的理论屈光度值及预计理想植入位置植入人眼时,A常数越大,人眼光学系统的MTF曲线越高,但当人工晶状体屈光度按照实际的0.5 D间隔就近原则植入屈光度近似的人工晶状体时,由A常数计算的理论屈光度与实际植入屈光度间的差值与人眼光学系统的MTF曲线则无明显相关性。等双凸球面型人工晶状体植入人眼的MTF曲线高于凸平型人工晶状体。结论当人工晶状体植入人眼理想位置时,A常数越大,人眼获得的成像质量越高,人工晶状体的光学结构对人眼的成像质量有一定的影响,结论对临床上不同A常数的人工晶状体实际选择和对人工晶状体设计具有一定的指导意义。     

偏心和旋转对非球面Toric人工晶状体成像质量影响的实验研究

目的：通过对Toric人工晶状体（IOL）的球差进行自动优化,理论设计不同球差的Toric IOL,并且对其旋转、偏心的耐受性及成像规律进行研究。方法：实验研究。在模型眼中对Toric IOL球差进行优化,分别优化球面结构,IOL前、后表面曲率半径和厚度及Toric IOL的前表面非球面系数,目标设计获得-0.26、-0.1 和0 μm球差的Toric IOL。在计算机光学模拟系统中,球面和非球面Toric IOL沿其X轴分别偏心0.25、0.50、0.75 mm,在3 mm和5 mm瞳孔直径下,评价其对调制传递函数（MTF）的影响;使其旋转3°、5°、10°,在4 mm瞳孔直径下评价其对MTF的影响。结果：在居中时随着瞳孔直径的增大,非球面Toric IOL成像质量下降低于球面Toric IOL;但在3 mm瞳孔偏心0.50 mm时,-0.26 μm的Toric IOL的成像质量下降并且低于0 μm和-0.1 μm的Toric IOL;5 mm瞳孔直径时偏心0.75 mm,-0.26 μm球差Toric IOL的MTF与球面IOL接近,而0 μm和-0.1 μm球差的Toric IOL的MTF略优于球面Toric IOL。旋转3°和5°时,非球面Toric IOL MTF仍高于球面IOL;旋转10°时,非球面Toric IOL高空间频率的MTF已经接近或低于球面IOL。结论：-0.26 μm球差的Toric IOL居中时有良好的成像质量,但偏心耐受性较差。对Toric IOL球差的适量的优化,可以提高模型眼的成像质量,同时保持对偏心和旋转误差的耐受性,使其在综合条件下获得更好的光学质量。     

非球面人工晶状体在个体化人眼模型中成像质量的研究

目的 根据不同患者眼部解剖参数建立个体化眼模型,研究植入不同设计的人工晶状体（IOL）后的光学表现.方法 计算机数字模拟实验.采用Pentacam眼前节分析系统、IOL Master采集白内障摘除联合IOL植入术后人眼结构数据,应用ZEMAX光学设计软件建立个体化眼模型,分别模拟植入不同设计的3种非球面IOL（SofPort AO、Tecnis Z9000、FY60AD）和1种球面IOL（YA60BBR）,计算这些IOL眼3 mm、4 mm、5 mm瞳孔下的调制传递函数（MTF）和对比敏感度函数（CSF）曲线.结果 随瞳孔直径增加,全眼MTF、CSF曲线高度下降;3 mm瞳孔下,个体化眼模型中3种非球面IOL的MTF和CSF曲线与球面IOL接近;5 mm瞳孔下,个体化眼模型植入4种IOL后MTF和CSF曲线差异明显,不同解剖结构参数个体获得最佳MTF和CSF曲线的IOL种类不同,在空间频率较高时更加明显.结论 根据人眼解剖参数建立个体化眼模型可以模拟该个体眼睛光学系统的光学质量.不同解剖结构的人眼光学系统获得最佳视觉质量所需的IOL种类不同.     

球面和非球面人工晶状体倾斜和偏心对视觉质量的影响

目的 研究超声乳化白内障吸除术后球面和非球面人工晶状体(intraocularlens,IOL)的倾斜和偏心及其对高阶像差(higher-order aberrations,HOAs)和视觉质量的影响.方法 前瞻性研究.取50例单纯性老年性白内障患者60只眼,30只眼随机植入AMO公司的球面IOLSensar AR40e,30只眼植入非球面IOLTecnisZA9003.术后3到4个月,检测患者在5.0mm瞳孔下的HOAs以及5、10、15、20、25、30周每度(cycles per degree,cpd)空间频率下的调制传递函数(modulation transfer function,MTF).通过Scheimpflug像,测量IOL的倾斜与偏心.比较两组间倾斜度和偏心值、HOAs及各空间频率下去除低阶像差的MTF(MTF(HOA))值.使用多元回归分析来确定倾斜和偏心对HOAs和视觉质量的影响.结果 光学部倾斜AR40e组(2.99±0.94)°,ZA9003组(2.98±1.15)°.光学部偏心AR40e组(0.30±0.13)mm,ZA9003组(0.31±0.14)mm.组间倾斜和偏心差异无统计学意义(Z=-0.044,-0.525,P=0.965,0.600,Mann-WhitneyU检验).总4阶球差,AR40e组(0.366±0.163)μm大于ZA9003组(0.027±0.072)μm,差异有统计学意义(t=-10.386,P=0.000).ZA9003组在5.0mm瞳孔直径下各频段的MTF(HOA)值均高于AR40e组,有统计学意义(P＜0.05).两组IOL倾斜和偏心对各自的HOAs及各频段的MTF(HOA)值均无明显影响.结论 当IOL的倾斜和偏心在正常限度内时,不会危害非球面IOL对球差的补偿作用,不足以导致视觉质量的下降.     

白内障术后不同设计与不同材料人工晶状体眼高阶像差分析

目的 利用波阵面像差仪分析不同设计、不同材料的折叠式人工晶状体植入患眼术后高阶像差的特点，旨在指导临床合理选择人工晶状体。方法 随机选取自愿接受超声乳化合并人工晶状体植入手术的白内障患者101人105眼，随机分为四组：A组植入一片式疏水性丙烯酸酯（Acrysof SA60AT）人工晶状体32例32眼；B组植入一片式亲水性丙烯酸酯（Isotechnics HP25B）人工晶状体30例36眼；C组植入三片式疏水性丙烯酸酯（Sensar AR40e）人工晶状体20例20眼{D组植入三片式疏水性丙烯酸酯（Acrysof MA60MA）人工晶状体15例15眼。其中4例8眼为左右眼自身对比。各组年龄之间具有可比性。术后3m观察患眼高阶像差的变化（WaveLight像差分析仪）。结果1、在瞳孔直径为4．0mm、5．0mm时，B组的高阶像差均方根（RMSh）值明显高于C组（P〈0．05）。2、在瞳孔直径为4．0-6．0mm时，B组的（RMS3）值明显高于C组（P〈0．05）。3、在瞳孔直径为6.0-7．0mm时，A组的球差（C12）值显著高于C组（P〈0．05）。结论 1、从波阵面像差角度分析全长13．Omm人工晶状体的光学质量和囊袋稳定性优于全长12．5mm人工晶状体。2、在瞳孔直径为6．0-7．0mm时，植入光学部周边前后面均为方型直角锐边设计的双凸型（前面较凸）人工晶状体患眼的球差高于植入光学部周边前圆后方（后表面直角锐边）设计的双凸型（前后凸度相同）人工晶状体的患眼。3、亲水性和疏水性丙烯酸酯人工晶状体眼之间高阶像差无差异。4、相同设计的一片式和三片式丙烯酸酯人工晶状体眼之间高阶像差无差异。     

不同光学结构人工晶状体的像差

目的：比较不同光学结构的人工晶状体植入人眼后的单色光像差，为人工晶状体的设计提供理论依据。方法：采用Gullstrand Ⅰ号模型眼为基础，运用光路追迹程序计算不同光学结构的人工晶状体植入人眼后成像的5种单色光像差，运用Microsoft Excel软件对计算结果做曲线图。结果：不同光学结构的人工晶状体均存在单色光像差，其中球差的影响最明显。结论：一些特定结构的人工晶状体具有较好的成像质量。     

无晶状体眼内植入人工晶状体的理论值探讨

目的：探讨无晶状体眼内植入人工晶状体的理论值计算方法。
　　方法：以Gullstrand （1号）模型眼及标准人工晶状体眼部分数据为基础,应用几何光学理论进行数理推导,从无晶状体眼内植入后房型人工晶状体理论值计算入手,总结出个性化角膜数据计算法;得出无晶状体眼内植入人工晶状体的理论值与角膜前表面曲率半径（ r1）、角膜后表面曲率半径（r2）、角膜厚度（T）、眼视轴长（L）、有效人工晶状体位置（ ELP）的数理关系。
　　结果：应用个性化角膜数据计算法,可计算出无晶状体眼内植入人工晶状体的理论值。
　　结论：各类无晶状体屈光不正眼,通过植入适度的人工晶状体,均可成为配合性正视眼。     

调制传递函数和对比敏感度函数评价LASIK术后早期视觉质量的研究

目的:应用调制传递函数(modulation transfer function,MTF)检查和对比敏感度函数(contrast sensitivity function,CSF)检查评价近视患者准分子激光原位角膜磨镶术(Laser in situ keratomileusis,LASIK)术后视觉质量的变化。方法:前瞻性研究。47例92眼行LASIK手术的患者按照术前验光度数分为低度近视组(A组)、中度近视组(B组)、高度近视组(C组)。术前等效球镜值分别为-2.28±0.48D,-4.54±0.97D,-6.86±1.17D。分别于术前,术后1wk;1,3mo检查裸眼视力(the uncorrected visual acuity,UCVA)、最佳矫正视力(best-corrected visual acuity,BCVA)、屈光度、波前像差、3mm和5mm瞳孔下的MTF和昼视及夜视视远状态下的CSF。利用德国Zeiss公司WASCAAnalyer波阵面像差仪检查三组患者在3mm和5mm瞳孔下去掉高阶像差后的MTF曲线,将图像扫描并载入至Engauge Digitizer4.1数字化软件,得出一定空间频率下的MTF值;利用Optical6500对比敏感度测试灯箱(美国STEREO OPTICAL公司)测量患者在昼视及夜视视远状态下的CSF值。对数据进行配对t检验。结果:(1)术后1wk,CSF值与术前相比有明显下降。术后3mo,只有明环境下低空间频率和暗环境下低中度近视组的低空间频率的CSF值可以恢复至术前。近视度数越高,中高空间频率的CSF值越不容易恢复至术前。(2)3mm瞳孔条件下低度近视组100L/mm,150L/mm,300L/mm空间频率的子午曲线和中度近视组50L/mm空间频率的子午曲线的MTF值,在术后7d与术前相比已经无统计学差异。3mm瞳孔条件下中度近视组150L/mm,200L/mm,300L/mm空间频率的弧矢曲线、高度近视组250L/mm空间频率下的子午曲线的MTF值和5mm瞳孔条件下低度近视组100L/mm,300L/mm,400L/mm空间频率下的子午曲线、中度近视组400L/mm,500L/mm空间频率下的弧矢曲线,200L/mm,400L/mm空间频率下的子午曲线,高度近视组全部空间频率下的弧矢曲线,100L/mm,200L/mm,300L/mm空间频率下的子午曲线的MTF值术后3mo可恢复到术前水平。其余所有空间频率下的MTF值均能在术后1mo恢复至术前水平。结论:(1)MTF值比CSF值恢复更早,只有部分低空间频率的CSF值可以恢复至术前,而所有的MTF值均能恢复至术前水平。(2)MTF值在术后早期可以更早更全面和客观的反映出视觉质量的提高。(3)利用Carl Zeiss公司WASCA Analyer波阵面像差仪检测患者MTF可以更立体全面客观的反映术后人眼光学系统的改变。     

带虹膜隔后房型人工晶状体植入术的临床应用

目的探讨治疗虹膜缺损的外伤性白内障或无晶状体眼的有效方法。方法总结、分析13眼外伤性白内障或无晶状体眼因虹膜缺损接受带虹膜隔后房型人工晶状体植入手术的术后疗效。随访时间6~20个月。其中人工晶状体Ⅰ期植入4眼,Ⅱ期植入9眼。13眼均植入德国Morcher公司生产的67G型单体型聚甲基丙烯酸甲酯(PMMA)后房型人工晶状体,其光学部直径5.0 mm;光学部外周黑色环为虹膜隔,宽2.5 mm,虹膜隔与光学部整体直径10.0 mm;虹膜隔外连两个有缝线固定小孔的C形襻。人工晶状体总长12.5 mm。除3例行白内障囊外摘出联合人工晶状体植入术外(其中1例同时植入晶状体囊袋张力环),余均为用10-0聚丙烯缝线行三点法后房型人工晶状体巩膜缝线法固定术。结果术后矫正视力1.0者1眼,0.5~0.8者4眼,0.1~0.4者5眼,<0.1者3眼。全部患眼畏光症状消失。术后无人工晶状体脱位等并发症发生。结论带虹膜隔后房型人工晶状体植入手术是治疗虹膜缺损白内障或无晶状体眼安全、有效的方法。     

Optical performance after bilateral implantation of apodized aspheric diffractive multifocal intraocular lenses with +3.00‐D addition power

Purpose: To determine whether bilateral implantation of an aspheric apodized diffractive multifocal intraocular lens (IOL) with +3.00 diopters (D) results in optical adverse effects compared with an aspheric monofocal IOL. Methods: In a prospective, randomized study of 204 eyes (102 patients) with bilateral implantation of an AcrySof ReSTOR SN6AD1 IOL or an AcrySof IQ SN60WF IOL, binocular uncorrected (UDVA) and corrected distance visual acuities (CDVA), uncorrected (UIVA) and distance‐corrected intermediate visual acuities (DCIVA), uncorrected (UNVA) and distance‐corrected near visual acuities (DCNVA), defocus curve, intraocular straylight, wavefront aberrations, modulation transfer functions (MTF) and patient questionnaires were evaluated postoperatively. Results: Both groups resulted in similar UDVA and CDVA (p > 0.05), whereas the multifocal IOL group performed significantly better UIVA and DCIVA at 50, 60 cm, and better UNVA and DCNVA at 40 cm (p ≤ 0.001). Higher intraocular straylight was obtained in the multifocal IOL group (p = 0.016). Total, higher‐order, spherical and coma aberrations performed similar in both groups (p > 0.05). MTF was lower in the multifocal IOL group than in the monofocal IOL group with 3.0‐mm pupils at 5 and 10 cycles per degree (cpd). Although patients in the multifocal IOL group complained more glare/flare, problems with night vision, and halos, they reported excellent spectacle independence, and high satisfaction. Conclusions: Compared with the AcrySof IQ IOL, the ReSTOR SN6AD1 IOL provided excellent visual outcomes, satisfactory spectacle independence without compromising wavefront aberrations; however, optical adverse effects with respect to higher intraocular straylight and lower MTF at lower spatial frequency were demonstrated.     

Alpha角对多焦点人工晶状体植入术后视觉质量影响

研究不同Alpha角对多焦点人工晶状体（MIOL）植入术后视觉质量的影响,指导功能性IOL的应用。方法：前瞻性临床研究。选取2016年12至2018年10月就诊于潍坊眼科医院行白内障超声乳化吸除联合MIOL植入术患者56例（74眼）,根据Alpha角大小（角膜上视轴与光轴的距离α）分为3组： A组12眼（0 mm<α≤0.2 mm）,B组38眼（0.2 mm<α≤0.4 mm）,C组24眼（α>0.4 mm）。术后随访3个月,记录裸眼远、中、近视力以及调制传递函数、眩光、光晕等情况。数据采用卡方检验、方差分析进行统计。结果：B组和C组光晕和眩光发生率高于A组,差异有统计学意义（χ2 =38.372,P=0.01）; 3组间术后3个月远、中、近视力比较差异无统计学意义（均P>0.05）;3组间MTF值在0～30 c/d范围差异无统计学意义（P>0.05）;夜间远视、重影、混合焦点、星芒的发生率差异均无统计学意义（均 P>0.05）。结论：当Alpha角大于0.4 mm时,植入MIOL会增加眩光和光晕的发生,所以Alpha角>0.4 需谨慎考虑使用MIOL。     

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.     

植入可调节人工晶状体和多焦点人工晶状体后视功能的对比研究

目的比较超声乳化白内障吸除术后植入可调节人工晶状体和多焦点人工晶状体的视功能。方法32例年龄相关性白内障患者根据自愿原则,采用非随机对照方式分成两组,试验组13例患者（24只眼）植入1CU可调节人工晶状体,对照组19例患者（30只眼）植入Array多焦点人工晶状体。术后3个月使用标准对数视力表检测患者最佳矫正视力及在最佳矫正视力基础上获得的近视力、近点及调节幅度、立体视觉。检查结果以年龄作为协变量,进行成组设计定量资料一元协方差分析。结果随诊期间所有患者均无明显的术后并发症。术后3个月试验组最佳矫正视力为4．96±0．15,对照组为5．02±0．08,两组比较差异无统计学意义（P=0．085）。试验组术后最佳矫正视力基础上获得的近视力为4．65±0．15,对照组为4．60±0．10,两组比较差异无统计学意义（P=0．398）。试验组术后主观近点为（56±9）cm,对照组为（61±11）cm,两组比较差异无统计学意义（P=0．80）。试验组术后调节幅度为（1．30±0．40）D,对照组为（1．20±0．36）D,两组比较差异无统计学意义（P=0．093）。试验组术后立体视觉为43．24”±18．25”,对照组为60．00”±23．09”,两组比较差异无统计学意义（P=0．543）。结论植入1CU可调节人工晶状体的患者术后可在保持最佳远视力的同时获得一定的近视力。两种人工晶状体在矫正远视力、远矫下近视力、主观近点、术后调节幅度及近距矫正基础上的立体视觉检查方面均无统计学意义。     

两种拟调节型人工晶状体植入术后视功能对比分析

目的 比较超声乳化术后植入可调节人工晶状体和多焦点人工晶状体的视功能.方法 30例白内障患者按自愿原则,采用非随机对照方式分成两组,试验组①10例患者(10只眼)植入Tetraflex可调节人工晶状体.试验组②20例患者(30只眼)植入+3.0D ReSTOR多焦点人工晶状体.术后6个月以ETDRS视力表检测患者最佳矫正远视力及在最佳矫正远视力基础上获得的近视力、中距离视力,综合验光仪检测近点及调节幅度.结果 随访期间所有患者均无明显的术后并发症.试验组①最佳矫正远视力为(-0.21±0.06)LogMAR,近视力为J3/40cm,试验组②为(-0.23±0.09)LogMAR,近视力为J1/35cm,两组比较近视力差异有统计学意义(P=0.035).试验组①术后主观近点为(39±10)cm,试验组②为(35±9)cm,两组比较差异无统计学意义(P=0.80).试验组①术后调节幅度为(1.94±0.13)D,试验组②为(2.08±0.63)D,两组比较差异有统计学意义(P=0.048).结论 可调节人工晶状体与多焦点人工晶状体植入术后均可使患者的视近困难得以改善.医生应根据患者情况为其选择合适的人工晶状体.

Abstract：

Objective To compare the visual performance of accommodative IOLS and that of multifocal IOLs implantation after phacoemulsification. Methods A total of 40 eyes from 30 patients undergoing phacoemulsification received intraocular lens based on the principle of voluntary. Ten eyes from 20 patients who had implantation of Tetraflex accommodative intraocular lens were randomized into group 1. Thirty eyes from 20 patients who had implantation of +3.0 aspheric ReSTOR multifocal intraocular lens were randomized into group 2. Main outcome measures included best corrected distance visual acuity, distance corrected near vision, near point, intermediate vision, and the accommodation amplitude. All the clinical data were obtained at 6months postoperatively. Results No patients had undergone any complications. At 6 months postoperatively,best corrected distance visual acuity were similar between the groupl and group2 (-0.23± 0.09LogMAR versus-0.14 ± 0.08LogMAR, P =0.085). Distance corrected near vision were similar between the two groups (J3/40cm versusJ1/35cm, P =0.035). Subjective near point were similar between the two groups [(39± 10) cm versus (35± 9) cm F=0.065, P=0.80]. The accommodation amplitude were similar between the two groups [(1.94± 0.13)D versus (2.08± 0.63)D, P =0.093]. The defocus line showed a double-peak in group 2 and single peak in group 1 which declined at intermediate distance. Conclusions Both accommodative IOLs and multifocal IOLs can correct presbyopia effectively after operation. It is best to prefer the proper IOLs for patients.     

非球面人工晶状体植入术后偏心和倾斜与视觉质量的相关性研究

目的：探讨新型眼前节扫频光相干断层扫描仪CASIA2测量年龄相关性白内障患者植入非球面人工晶状体(IOL)术后的偏心和倾斜与视觉质量的关系。

方法：观察性研究。纳入年龄相关性白内障术后1mo随访的患者62例90眼。应用CASIA2于散瞳后测量IOL偏心和倾斜的大小和方向,进行3次测量,取其矢量平均值。再使用KR-1W波前像差仪和双通道视觉质量分析系统(OQAS)进行测量,获取4、6mm瞳孔直径下全眼总高阶像差(tHOA)、球面像差(SA)、彗差(Coma)、客观散射指数(OSI)、调制传递函数截止频率(MTF cut off)和斯特列尔比(SR)等参数。

结果：IOL偏心与4mm瞳孔直径下SA(r=0.347,P=0.001)和OSI(r=0.343,P=0.002)成正相关,与MTF cut off(r=-0.244,P=0.032)呈负相关,与tHOA、Coma和SR无相关。IOL倾斜与4mm瞳孔直径下MTF cut off(r=-0.345,P=0.002)和SR(r=-0.256,P=0.023)呈负相关,与tHOA、SA、Coma、OSI均无相关性。IOL的偏心和倾斜与6mm瞳孔直径下的tHOA、SA、Coma、MTF cut off、SR均无相关性。

结论：年龄相关性白内障患者植入非球面IOL后,除IOL偏心与4mm瞳孔直径下SA呈弱相关性,偏心和倾斜与其余各项高阶像差均无明显相关性,与视觉质量参数OSI值及MTF cut off值弱相关,提示临床医生在精准白内障手术中关注高阶像差及视觉质量。     

ICU人工晶状体植入术后的早期临床效果

目的:比较白内障超声乳化术联合ICU(德国HumanOptics公司)可调节人工晶状体植入术后效果与传统单焦后房型UV型(日本HOYA公司)人工晶状体植入术后效果之间的差异。方法:所有患者均行白内障超声乳化联合人工晶状体植入术。比较18例(20眼)患者ICU可调节人工晶状体植入及20例(20眼)患者UV型后房型人工晶状体植入术后1wk、1mo时的裸眼远视力、最佳矫正远视力、近视力(35cm)及矫正远视力的近视力(35cm)、主观调节近点、10g/L硝酸毛果芸香碱滴眼30min后利用A型超声波测量前房深度(anterior chamber depth,ACD)变化等多项指标之间的差异。结果:两组数据间比较,除术后远视力及最佳矫正远视力无显著性差异外,其它指标间比较均有非常显著性差异(P<0.01)。结论:ICU可调节人工晶状体相对于传统单焦后房型人工晶状体具有更高调节力、更佳的近视力,同时也具有良好的远视力。但术后调节幅度有限,长期效果如何有待进一步观察、研究。     

Potential of the 1 CU accommodative intraocular lens

AIM: To assess the accommodative power of a new foldable monofocal intraocular lens. METHOD: A prospective randomised non-masked clinical interventional study. The study included 40 patients attending the hospital for cataract surgery and who were randomly distributed into a study group receiving a new foldable monofocal intraocular lens with flexible haptics, and a control group receiving a standard foldable intraocular lens. Mean follow up period was 8.51 (SD 1.34) months (range 4-11 months) Standard cataract surgery consisted of clear cornea incision, capsulorrhexis, phacoemulsification, and intraocular lens implantation, with topical anaesthesia. The main outcome measures were preoperative and postoperative visual acuity for near and distance; range of accommodation; change in anterior chamber depth. RESULTS: In the study group compared with the control group, range of accommodation was significantly (p = 0.01) higher (1.01 (SD 0.4) dioptres versus 0.50 (0.11) dioptres) and change in anterior chamber depth was significantly more pronounced (0.82 (0.30) versus 0.40 (0.32), p = 0.01). Both groups did not vary significantly in best corrected vision (0.94 (0.12) versus 0.93 (0.18); p = 0.74). CONCLUSION: During a mean follow up period of 8 months after implantation, the new foldable monofocal intraocular lens with flexible haptics showed an accommodative power of about 1 dioptre, which was significantly higher than the accommodative power of a conventional monofocal flexible intraocular lens. The difference in the accommodative power between the two intraocular lenses was paralleled by a difference in the change of the anterior chamber depth.     

Comparison of 6-month results of implantation of the 1CU accommodative intraocular lens with conventional intraocular lenses

OBJECTIVE: To evaluate the clinical results of implantation of the new 1CU accommodative intraocular lens (IOL) in cataract patients and to compare results with those of conventional IOLs. DESIGN: Nonrandomized comparative trial. PARTICIPANTS: Twenty eyes of 20 patients (mean age = 65.8+/-13.3 years) in the 1CU group and 20 eyes of 20 patients (mean age = 67.4+/-11.6 years) in the control group. METHODS: All patients underwent phacoemulsification and IOL implantation. The 1CU accommodative lens was used in 20 eyes, and conventional IOLs (polymethyl methacrylate, hydrophilic or hydrophobic acrylate) were used in the control group. Patients were observed prospectively, and 6-month data were analyzed. MAIN OUTCOME MEASURES: Accommodative ranges determined by 3 different methods (near point, defocusing, and retinoscopy). Secondary outcome measures were (1) increase of anterior chamber depth after topical application of 1% cyclopentolate eyedrops and (2) distance-corrected near visual acuity with Birkh?user reading charts at 35 cm. RESULTS: We observed a higher accommodative range with all 3 methods (mean = 1.83+/-0.49 vs. 1.16+/-0.27 diopters [D] [near point], 1.85+/-0.43 vs. 0.64+/-0.21 D [defocusing], and 0.98+/-0.55 vs. 0.17+/-0.22 D [retinoscopy]), a larger increase of anterior chamber depth after cyclopentolate eyedrops (mean = 0.42+/-0.18 vs. 0.11+/-0.06 mm), and better distance-corrected near visual acuity (median = 0.4 vs. 0.2) in the 1CU group relative to the control group. All differences between the 2 groups were statistically highly significant (P<0.001). CONCLUSIONS: In the present study, the 1CU accommodative IOL showed increased accommodative range and better near visual acuity than a control group with conventional IOLs. Further research is necessary to confirm these results in masked, randomized, prospective studies and to confirm further the accommodative power of this group of new IOLs.     

景深对超声乳化术后假晶状体眼伪调节的影响

目的探讨白内障超声乳化术后假晶状体眼的景深对伪调节的影响。方法白内障患者30例（60眼），年龄（62.77±5.27）岁（50-70岁），其中44眼为假晶状体眼。测量屈光状态、调节幅度、瞳孔直径。睫状肌麻痹后，分别在不矫正散光和配戴人工瞳孔镜片（直径2.5mm）情况下测量单眼调节幅度。采用SPSS11.0统计软件行统计学分析。结果假晶状体眼的移近法单眼调节幅度为（2.35±1.14）D。散光和人工瞳孔对调节幅度的影响分别为0.21D和0.16D。调节前、后瞳孔直径分别为（4.52±0.66）mm和（2.72±0.64）mm。单眼调节幅度与调节前后瞳孔直径变化无相关性（r=0.164，P=0.305）。睫状肌麻痹时不矫正散光和配戴人工瞳孔镜片的单眼调节幅度分别为（0.61±0.18）D和（0.77±0.14）D。结论对于白内障超声乳化术后的假晶状体眼，瞳孔和单纯近视散光所致景深是伪调节的产生机制之一，但不是主要机制。增大景深不是改善伪调节的主要方法，今后还需要从人工晶状体本身的设计或在眼内的位置变化等方面来研究伪调节的机制和相应的改善方案。