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...     

儿童前房深度与各屈光参数关系

目的:研究前房深度与年龄、晶状体屈光力、角膜屈光力及眼轴之间的关系.方法:通过睫状肌麻痹检影验光及光学生物测量仪(IOL Master)获得44例88眼的屈光不正度数、眼轴、角膜屈光力、前房深度等参数,经计算得到晶状体度数.直线相关与回归比较前房深度和年龄及各屈光参数之间的关系.结果:受试者44例88眼,平均年龄9.04±2.39岁,等效球镜(SE)-3.50 ～ +8.75D;三组间前房深度无明显差别,男性与女性间前房深度无差别;前房深度与年龄之间存在负相关关系,相关系数r=-0.323,ACD/AL与年龄呈负相关,相关系数r=-0.516;晶状体屈光力与年龄呈正相关,相关系数为0.414;前房深度与晶状体屈光力呈负相关,相关系数r=-0.392;角膜屈光力与年龄呈负相关,相关系数r=-0.461;前房深度与角膜屈光力之间呈微弱的正相关,相关系数r=0.295.结论:受试儿童眼球的前房随年龄逐渐变浅,在眼轴中所占的比例不断降低;由角膜、晶状体、房水及前房组成的组合透镜屈光力随年龄下降,同时玻璃体腔变长,正符合儿童眼球正视化的要求.     

黏度5500 mPas硅油填充眼超声生物学测量的准确性

背景 硅油填充眼超声生物学测量的准确性和可行性是眼科诊疗过程中的难题,对硅油眼性白内障行超声乳化联合人工晶状体(IOL)植入术时IOL度数的计算造成困难.一些大型医院常采用光学测量仪IOLMaster实现对硅油填充眼的生物学测量,但其对屈光介质严重混浊的病例仍无法进行测量.曾有研究者采用超声改良法或眼轴分段测量法进行估算,但其研究结果可能由于硅油黏度的不同而差异较大.目的 探讨超声对黏度5 500 mPas硅油填充眼生物学测量的计算方法,为超声法对不同黏度硅油填充眼进行生物学测量提供方法学参考依据. 方法 采用B型超声仪于37℃下对高度分别为20、24和28 mm的平衡盐溶液进行测量,并与黏度5 500 mPas硅油的相应测量高度进行比较,以得到计算硅油眼实际眼轴长度(AL)的公式.收集于2012年5月至2014年3月在青岛市海慈医疗集团接受黏度为5 500mPas硅油填充治疗的复杂性视网膜疾病患者30例32眼,按实际AL分为AL＜26 mm组(16例18眼)和AL≥26 mm组(14例14眼),分别于硅油取出术前1d行B型超声、IOL Master测量AL,并于术后3个月用A型超声及B型超声测量AL.对不同方法测量的AL值进行差异比较和相关分析,并对手术前后受检眼玻璃体腔长度和屈光度进行比较.结果 B型超声波在黏度5 500 mPas硅油中的传播速度为1 023 m/s,超声波在硅油眼与正常玻璃体腔中测算AL的校正系数为0.668,校正AL=角膜顶点至晶状体后极或囊膜中央点距离+0.668×晶状体后极或囊膜中央点至黄斑距离.AL＜26 mm组和AL≥26 mm组受检眼用术前B型超声校正公式法、IOLMaster测量法、术后A型超声测量法和术后B型超声测量法测量的AL值的总体比较,差异均无统计学意义(F=0.108,P=0.955;F=0.011,P=0.998);硅油取出术前,B型超声校正公式法测量的AL值与IOLMaster测量法、术后B型超声测量法和术后A型超声测量法间测得的AL值均呈明显正相关(AL＜26 mm组:r=0.876、0.921、0.809,均P＜0.01;AL≥26 mm组:r=0.943、0.956、0.955,均P＜0.01).硅油取出术前1d,B型超声测量的玻璃体腔长度校正值为(20.78±2.13)mm,硅油取出术后3个月测量的玻璃体腔实际长度为(20.89±2.16) mm,二者间差异无统计学意义(t=0.795,P=0.219).受检眼中16眼行IOL植入术后平均屈光度为(-1.25±1.69)D,与术前保留的(-1.50±0.00)D比较,差异无统计学意义(t=0.585,P=0.284).结论 B型超声法对硅油填充眼的生物学测量准确、简便,用于临床的可行性较好.     

Olsen公式对高度近视合并白内障患者术后屈光力的预测性

目的：探讨Olsen公式对高度近视合并白内障患者术后屈光力的预测性。

方法：回顾性分析自2016-10-10/2019-08-20于我院行白内障超声乳化联合人工晶状体(IOL)植入术的高度近视合并白内障患者65例101眼,根据眼轴长度(AL)进行分组,A组(26mm30mm)22例31眼。采用IOL Master自带的SRK/T、Haigis和Olsen公式计算术后理论屈光度(即所植入IOL度数对应的各公式的预测屈光度),并记录术后3mo实际屈光度,计算绝对屈光误差(MAE)。

结果：三组患者采用Olsen公式对应的术后3mo MAE分别为0.15(0.04,0.22)、0.19(0.14,0.27)、0.26(0.115,0.455)D,无明显差异(P>0.05),且对于相同眼轴长度范围的患者,采用Olsen公式对应的术后3mo MAE最小。采用Bland-Altman法分析采用三种IOL屈光度计算公式对应的术后理论屈光度与术后3mo实际屈光度的一致性,结果表明,术后3mo实际屈光度与Olsen公式对应的术后理论屈光度最为接近,与SRK/T公式对应的术后理论屈光度一致性最差。

结论：Olsen公式对高度近视合并白内障患者术后屈光力的预测准确性和稳定性优于SRK/T、Haigis公式,且Olsen公式受眼轴长度影响最小。     

六种新一代人工晶状体屈光力计算公式的预测准确性比较

目的:比较六种新一代人工晶状体(intraocular lens,IOL)屈光力计算公式[Barrett UniversalⅡ(BUⅡ)、Emmetropia Verifying Optical(EVO)、Hill-Radial Basis Function (Hill-RBF)、Kane、Ladas Super Formula(LSF)、T2]和传统公式(Haigis、Hoffer Q、Holladay 1、SRK/T)的准确性。方法:纳入2022年1—6月于温州医科大学附属眼视光医院接受白内障手术患者。收集患者的年龄、性别、眼轴(axial length,AL)、平均角膜曲率(mean keratometry,K_mean)、前房深度、IOL常数和屈光力,术后医学验光结果。对上述10种公式进行准确性分析,包括平均预测误差(mean prediction error,ME)及其标准差、平均绝对预测误差(mean absolute prediction error,MAE)、绝对预测误差中位数(median absolute prediction error,Med...     

眼轴》28mm高度近视眼的晶状体超声乳化和后房型人工晶状体植入

目的 评价眼轴>28mm的高度近视眼的晶状体超声乳化和后房型人工晶状体(intraocular lens,IOL)植入手术的效果。方法 回顾性研究2000-10/2002-01 41例54眼的临床和随访材料。患者年龄19—81(平均56.3±14.0)岁。平均眼轴为30.58±1.41(28.18～34.0)mm。术前戴镜度数在-12～-24D。除3例(4眼)为透明晶状体外,其他为核性和混合性白内障。1眼手术前做了预防性视网膜光凝。手术采用微流超声乳化晶状体,植入折叠IOL、或植入光学直径为6mm的硬性IOL于囊袋内。所有患眼的术前视力为光感～0.15。手术后随访患者10～26月。结果 10眼IOL度数在 6～ 11D,植入Acrysof折叠IOL;其余44眼为PMMA一体式IOL,度数范围在-6～ 5D。手术中4例后囊膜局部破裂,但未影响计划的手术操作。1例有少量晶状体皮质遗留于下方玻璃体,但眼压不高,视力0.3。手术后2眼有少量前房出血,1周内完全吸收。术后所有眼视力进步,未矫正视力为0.05,3眼;0.1～<0.5,28眼(52％);≥0.5的23眼(42％)。其中11眼获得0.8-1.5的良好视力。随访期间视力稳定,未发现视网膜脱离病例。结论 晶状体超声乳化和后房型IOL植入手术,对眼轴>28mm的高度近视眼是一种安全、有效的增视手术。     

角膜横径和晶状体厚度在Barrett UniversalⅡ人工晶状体计算公式中的应用价值

目的:探讨运用Barrett UniversalⅡ公式(BUⅡ公式)计算人工晶状体(intraocular lens,IOL)屈光力时,可选参数角膜横径,又称白到白(white-to-white,WTW)与晶状体厚度(lens thickness,LT)的实际应用价值。方法:采用单中心、前瞻性临床研究,连续纳入同一术者顺利进行白内障超声乳化吸除术联合MX60(IOL植入术患眼279眼,术前使用OA-2000非接触式光学生物测量仪测量眼部数据并计算IOL植入度数,代入BUⅡ公式保留或去掉可选参数WTW、LT计算预测结果,进一步根据患者眼轴长度(axial length,AL)分亚组分析。主要结局指标:随访患者至术后1个月以上,比较使用和未使用WTW和LT两个参数、BUⅡ公式预测误差(prediction error,PE)、绝对预测误差(absolute error,AE)、AE小于0.5 D所占比例。结果:总体1上,忽略WTW+LT,PE为-0.05 D(-0.26,0.18)(P=0.011),其他参数组合的PE与0比较差异无统计学意义(P>0.05)。各参数组合的AE比较差异...     

高度近视白内障患者人工晶状体屈光度数计算公式的选择

目的　比较SRK T(Sanders Retzlaff KvaffT)和SRK Ⅱ (Sanders Retzlaff KvaffⅡ )公式的特点 ,以提高高度近视白内障患者人工晶状体 (intraocularlens ,IOL)屈光度数计算的准确性。方法 (1)使用相同的生物参数 (眼轴长度和角膜屈光力 )和A常数 ,比较SRK T和SRK Ⅱ公式理论计算值的差异 ;(2 )对 86例 (130只眼 )高度近视白内障患者行超声乳化白内障吸除联合IOL植入术。分别采用SRK T和SRK Ⅱ公式计算IOL屈光度数 ,记录并比较不同眼轴长度患者按照两公式计算结果植入IOL术后实际屈光度数与预期屈光度数的差异。随访时间 3～ 2 4个月。结果　 (1)角膜屈光力为 4 3 0 0D时 ,两公式理论计算值比较差异无显著意义 (P >0 0 5 ) ,且两公式计算的屈光度数差值与眼轴长度无相关 (P>0 0 5 ) ;角膜屈光力为 39 0 0、4 1 0 0、4 5 0 0及 4 7 0 0D时 ,两公式理论计算值比较差异均有显著意义(P <0 0 5 ) ,且两公式计算的屈光度数差值与眼轴长度呈中、高度线性正相关 (P <0 0 5 )。(2 )按照SRK T和SRK Ⅱ公式计算结果植入IOL术后 ,术眼实际屈光度数与预期屈光度数差值分别为 0 0 8D和 -0 79D ,差异有显著意义 (P <0 0 5 )。结论　选择IOL屈光度数的计算公式 ,应综合考虑患者的眼轴长度和角膜屈光力等因素 ;其中     

有效晶状体位置预测的研究进展

有效晶状体位置(effective lens position,ELP)是指白内障术后人工晶状体(intraocular lens,IOL)的有效位置,对于白内障术后屈光状态的计算尤其重要,如今有许多研究发现了新的ELP预测方法,比如术前晶状体赤道平面预测ELP,沟到沟(angle to angle,ATA)预测ELP...     

三种襻型人工晶状体囊袋内植入后囊膜皱褶发生率的比较

目的： 比较植入不同襻型人工晶状体(IOL)后囊膜皱褶的发生率,以确定后囊膜皱褶发生的相关风险因素。

方法： 回顾性研究。收集行超声乳化白内障吸除+囊袋内IOL植入术的患者,所植入人工晶状体为两襻三片式IOL(HOYA PY60AD)、四襻一片式IOL(Bausch & Lomb AO)、两襻一片式IOL(AMO Tecnis ZCB00)中任意一种。收集纳入该研究的患者的年龄、性别、眼轴、眼压、人工晶状体类型。术后2d在裂隙灯下评估后囊膜皱褶形成情况。采用logistic回归分析确定后囊膜皱褶发生的风险指标。

结果： 一共收集187例242眼,其中80眼植入HOYA PY60AD IOL,81眼植入Bausch & Lomb AO IOL,81眼植入AMO Tecnis ZCB00 IOL。植入HOYA PY60AD IOL的患眼后囊膜皱褶发生率显著高于植入AMO Tecnis ZCB00 IOL者(56.3% vs 38.3%,P=0.027)。植入Bausch & Lomb AO IOL的患眼后囊膜发生率显著低于植入AMO Tecnis ZCB00 IOL(14.8% vs 38.3%,P=0.001)。多因素logistics回归分析显示人工晶状体类型和眼轴长度是影响皱褶发生的独立风险因素。相较于AMO Tecnis ZCB00 IOL,使用HOYA PY60AD IOL提高后囊膜皱褶发生风险\〖P=0.020,OR(95%CI)=2.145(1.129,4.073)\〗,使用Bausch & Lomb AO IOL降低后囊膜皱褶发生风险\〖P=0.001,OR(95%CI)=0.274(0.127,0.591)\〗; 眼轴越短,后囊膜皱褶发生风险越大\〖P=0.012,OR(95%CI)= 0.669(0.489,0.915)\〗。

结论： 在人工晶状体设计中,晶状体襻是重要考虑因素。相比于AMO Tecnis ZCB00 IOL,HOYA PY60AD IOL更容易出现后囊膜皱褶,Bausch & Lomb AO IOL不容易出现后囊膜皱褶; 眼轴较短的患眼更容易出现后囊膜皱褶。     

Optical formula to predict outcomes after implantation of accommodating intraocular lenses

PURPOSE: To analyze the effect of optical parameters on the outcomes of accommodating intraocular lens (IOL) implantation in cataract surgery. SETTING: Department of Ophthalmology, KULeuven University, Leuven, Belgium. METHODS: Thin-lens approximation optics were used to obtain a formula containing the following variables: axial length (AL), mean keratometry (Km), anterior chamber depth (ACD), and presumed anterior shift of the IOL (dACD). The influence of these variables was separately analyzed. RESULTS: The accommodative amplitude (AA) decreased with a longer AL and higher Km. The AA varied between -5.4 diopters (D) and 0.0 D in eyes with an AL between 20.0 mm and 28.0 mm and a Km between 38.0 D and 52.00 D. The dACD was also a significant factor influencing the AA. The ACD had less influence on the AA. CONCLUSION: The obtained formula could guide selection of candidates for accommodating IOL implantation.     

Phacoemulsification and implantation of an accommodating IOL after PRK

PURPOSE: To present a case of phacoemulsification and implantation of an accommodating intraocular lens (IOL) in a patient with cataract formation after previous refractive surgery. METHODS: A 50-year-old man, who initially had photorefractive keratectomy to correct moderate myopia, developed a cataract in one eye. He subsequently underwent phacoemulsification and implantation of a 1CU accommodating IOL, as he wished to remain spectacle independent. RESULTS: The patient's distance vision was fully restored. However, accommodative function, which was assessed using subjective and novice objective techniques, was only partially restored. CONCLUSIONS: Although the accommodating IOL fully restored the patient's distance vision, accommodative function was only partially restored.     

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.     

Synchrony dual-optic accommodating intraocular lens. Part 1: optical and biomechanical principles and design considerations

PURPOSE: To describe a dual-optic accommodating intraocular lens (IOL) based on theoretical considerations. SETTING: University and independent research group. METHODS: Ray-tracing analysis using optical modeling software (ZEMAXTM, Focus Software Inc., Tucson, Ariz) in a theoretical model eye was used to analyze lens configurations to optimize the accommodative and magnification effects of axial lens displacement. Finite-element modelling using a commercially available PC-based software package (COSMOS DesignSTAR) was applied to design the biomechanical parameters of the inter-optic articulations and optics. RESULTS: Ray-tracing analysis indicated that a dual-optic design with a high plus-powered front optic coupled to a minus posterior optic produced greater change in conjugation power of the eye compared to a single-optic intraocular lens and that magnification effects were unlikely to account for improved near vision. Finite-element modelling indicated that the 2 optics can be linked by spring-loaded haptics that allow anterior and posterior axial displacement of the front optic in response to changes in ciliary body tone and capsular tension. CONCLUSION: A dual-optic design linked by spring haptics increases the accommodative effect of axial optic displacement with minimal magnification effect and has promise for improving the performance of accommodative 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.     

Accommodating intraocular lenses

PURPOSE OF REVIEW: With the advent of interest in accommodative lenses as a solution for presbyopia and the growing baby-boomer demographic, ophthalmic surgeons will have the opportunity to provide this technology to facilitate near, intermediate, and distance vision for their patients. RECENT FINDINGS: At present, six corporate entities and lens designs are attempting to commercialize accommodative intraocular lens devices. One Food and Drug Administration (FDA) clinical trial has been completed and the first FDA-approved accommodating lens is available. SUMMARY: For the first time, ophthalmic surgeons will be able to provide a full range of visual focus in each eye of a patient to maintain binocular function while also avoiding the unwanted mesopic and scotopic visual disturbances that are experienced with monovision and multifocal lens technologies. Accommodative intraocular lenses could revolutionize not only cataract visual rehabilitation but also the surgical approach to presbyopia.     

Changes of the accommodative amplitude and the anterior chamber depth after implantation of an accommodative intraocular lens

Background

Modern cataract surgery is interested in recovery of the accommodative power. This investigation aimed at determining pseudophakic accommodation in subjects implanted with the accommodative Human Optics 1 CU intraocular lens after drug-induced ciliary muscle stimulation by measuring the objective refraction and the changes in anterior chamber depth in comparison with a PMMA intraocular lens with rigid haptics.

Methods

The studied sample involved 30 eyes of 30 patients undergoing cataract surgery due to age-related cataract. Patients were between 50 and 77 years of age (67.71±8.0). No randomization was performed. The 1 CU accommodative intraocular lens and the PMMA intraocular lens were implanted in 15 eyes of patients with an expected visual acuity of at least 0.7. Objective refraction under pilocarpine-stimulated ciliary muscle contraction was determined with a Hartinger coincidence refractometer. The anterior chamber depth was measured with Jäger’s Haag–Streit slit-lamp attachment. The accommodative amplitude and the anterior chamber flattening were calculated from the measured values.

Results

Twelve weeks after surgery the average accommodative amplitude in eyes with a 1 CU intraocular lens calculated from the refractive change under drug-induced stimulation was 0.48±0.36 D (with a maximum of 1.25 D). The measured change of anterior chamber depth under drug-induced stimulation was 0.3±0.32 mm (at a maximum of 0.9 mm). In the reference group with PMMA lenses, the mean accommodative amplitude derived from the refractive changes under drug-induced stimulation was 0.34±0.27 D (at a maximum of 0.85 D). The measured change in anterior chamber depth under drug-induced stimulation was 0.18±0.09 mm (at a maximum of 0.31 mm). No statistically significant differences were found between the two groups of lenses concerning change in anterior chamber depth and accommodative amplitude.

Conclusions

This investigations indicate a mean anterior 1 CU shift of only 0.32 mm and a maximum of 0.9 mm. The accommodative amplitudes measured with the Hartinger coincidence refractometer (mean value 0.47 D) correspond to these values. Similar conclusions may be drawn from existing investigative results of the reference group, which are on the same order of magnitude as those of the 1 CU group. Objective accommodation measurements are needed to evaluate commercially available accommodative intraocular lenses in a scientifically satisfactory manner. Objectively measurable parameters include changes of the anterior chamber depth as well as refraction, as determined for instance by coincidence refractometry and streak retinoscopy. Future studies should also consider the IOL properties, astigmatism, and pupillary diameter. This is the only way to identify pseudoaccommodation and a decisive factor for further development of accommodative artificial lenses.     

Subjective and objective performance of the Lenstec KH-3500 "accommodative" intraocular lens

AIM: To determine whether eyes implanted with the Lenstec KH-3500 "accommodative" intraocular lenses (IOLs) have improved subjective and objective focusing performance compared to a standard monofocal IOLs. METHODS: 28 participants were implanted monocularly with a KH-3500 "accommodative" IOL and 20 controls with a Softec1 IOL. Outcome measures of refraction, visual acuity, subjective amplitude of accommodation, objective accommodative stimulus response curve, aberrometry, and Scheimpflug imaging were taken at approximately 3 weeks and repeated after 6 months. RESULTS: Best corrected acuity with the KH-3500 was 0.06 (SD 0.13) logMAR at distance and 0.58 (0.20) logMAR at near. Accommodation was 0.39 (0.53) D measured objectively and 3.1 (1.6) D subjectively. Higher order aberrations were 0.87 (0.85) microm and lower order were 0.24 (0.39) microm. Posterior subcapsular light scatter was 0.95% (1.37%) greater than IOL clarity. In comparison, all control group measures were similar except objective (0.17 (0.13) D; p = 0.032) and subjective (2.0 (0.9) D; p = 0.009) amplitude of accommodation. Six months following surgery, posterior subcapsular scatter had increased (p<0.01) in the KH-3500 implanted subjects and near word acuity had decreased (p<0.05). CONCLUSIONS: The objective accommodating effects of the KH-3500 IOL appear to be limited, although the subjective and objective accommodative range is significantly increased compared to control subjects implanted with conventional IOLs. However, this "accommodative" ability of the lens appears to have decreased by 6 months post-surgery.     

Tetraflex可调节人工晶状体临床应用的初步观察

目的 观察白内障超声乳化联合囊袋内可调节人工晶状体植入术的效果.方法 病例对照研究.全部患者行白内障超声乳化联合囊袋内人工晶状体植入术,根据植入人工晶状体的不同分为试验组:22例(30只眼)植入可调节人工晶状体,对照组:22例(29只眼)植入单焦点人工晶状体.观察并记录术后6个月和12个月时术眼远、近视力,主观调节幅度,应用OCULUS Pentacam三维前段分析仪测量2%毛果芸香碱眼液诱导前后的前房深度变化值.各观察指标数据以均数±标准差表示.使用SPSS13.0软件对数据进行分析.采用两组独立样本t检验比较两组各观察指标,以P<0.05为差异有统计学意义.结果 术后随访期间,试验组患者的裸眼近视力和最佳远视力矫正后的近视力与对照组患者相比,有统计学差异(P=0.000),两组患者的最佳矫正视力差异无统计学意义(P>0.05);术后6个月时,应用主观移近法测得的主观调节幅度,试验组为(1.60±0.57)D,对照组为(1.10±0.70)D.前房深度变化值试验组为(0.50±0.37)mm,对照组为(0.08±0.06)mm.术后12个月时,应用主观移近法测得的主观调节幅度,试验组为(1.38±0.52)D,对照组为(1.06±0.61)D.前房深度变化值试验组为(0.30±0.27)mm,对照组为(0.10±0.09)mm.结论 与传统的单焦点人工晶状体相比,Tetraflex可调节人工晶状体可以为患者提供较好的近视力和主观调节幅度,但远期疗效有下降趋势.