应用Monovision矫正老视的研究进展

Monovision矫正方法常用于老视和老视前期患者,即一眼矫正看远,另一眼矫正看近,其机制是双眼间的模糊抑制,MV可应用于单焦点角膜接触镜,并且还可应用于人工晶状体植入术和PRK,LASIK等激光屈光手术中,以及目前最新的非激光手术—传导性角膜成形术。本文就MV矫正的机制、对双眼视力功能的影响以及研究进展作一综述。     

Monovision与老视矫正手术

Monovision(MV)矫正是一种成熟的矫正老视的方法,近10 a来,老视矫正手术逐渐开展,一些准分子激光角膜屈光手术(PRK、LASIK等)、激光角膜热成形术和传导式角膜成形术、人工晶状体植入术也采用MV矫正方法治疗老视,取得很好的效果,本文就MV矫正在这些老视矫正手术中的应用进行综述.     

激光手术矫正老视的应用和研究进展

尽管老视矫正方法日趋繁多,但手术矫正老视仍是屈光领域一个重大难题.近年来激光手术矫正老视逐渐得到重视.主要包括作用于角膜的激光老视手术如准分子激光原位角膜磨镶术、飞秒激光角膜基质内老视矫正术、激光角膜热成形术、角膜层间镜片植入术,以及作用于晶状体的飞秒激光晶状体老视矫正手术等.本文对激光矫正老视的临床应用和最新研究进展进行综述.     

Monovision的概念及其矫正老视的应用

Monovision（MV）概念已经有几十年的历史，应用于老视的矫正也有三十多年了，主要以接触镜应用最为广泛，近些年来随着屈光手术的广泛开展，应用MV技术设计手术矫正老视渐渐受到手术医生的青睐。     

老视矫正的多样化研究进展

配戴框架凸透镜是矫正老视的主要方式，如单光眼镜、双光眼镜、渐变多焦镜及其他新兴衍射镜片。屈光性手术也为矫正老视提供了新的途径，可分为角膜屈光性手术、晶状体摘除联合可调节型人工晶状体（IOL）植人手术以及巩膜屈光性手术。角膜屈光性手术通过改变角膜的屈光力而改变眼球的屈光状态，包括激光角膜手术和角膜层间植人物手术两类。晶状体摘除联合人工晶状体植人术的关键在于可调节型人工晶状体的研发，现有的单焦调节型及多焦调节型人工晶状体优点是减少眩光或光晕，获得较好的夜间视觉，临床效果仍需进一步研究。巩膜屈光性手术通过增加晶状体赤道部与睫状肌的距离治疗老视，包括睫状体前巩膜切开术、激光老视逆转术和巩膜扩张术。老视矫正逐渐向多样化发展，为不同需求的老视者提供了更多的选择。     

老视矫正方法的研究进展

目的老视矫正方法的日趋多样化。配戴框架凸透镜是矫正老视最常见的方式,包括传统的单光（单焦）眼镜及近年出现的双光（双焦）、渐变多焦眼镜及衍射镜片。屈光手术矫正老视可分为角膜屈光性手术、眼内晶状体摘除联合可调节型人工晶状体（IOL）植入手术和巩膜屈光性手术。角膜屈光性手术包括激光角膜手术、角膜层闻植入物手术及传导性角膜成形术。鼎状体摘除联合可调节IOL植入术的IOL可分为单焦和多焦调节型两种,有引起眩光或光晕等视觉症状的情况,疗效需进一步观察。巩膜手术视觉完整性并不理想,且可能出现严重并发症,仍需临床观察。同时monovision（MV）被越来越多的引入到老视矫正手术中并且取得了较好效果。老视矫正方法的多样化为不同的需求者提供更多的选择。     

老视及其矫正

老视是一种生理现象，不论屈光状态如何，每个人均会发生老视。随着人类社会的老龄化，老视的矫正问题成为我们日益严峻的挑战。本文拟就有关老视的调节机制及近年来一些矫正方法的原理、手术方式、临床应用结果作一综述。     

Peripheral visual acuity with monovision and other contact lens corrections for presbyopia

We have conducted two experiments to investigate the effect of monovision and other contact lens corrections for presbyopia upon peripheral visual acuity. In the first study, we measured binocular peripheral visual acuity using Landolt rings with seven subjects wearing a monovision correction. The Landolt rings were presented at eccentricities of 10, 20, 40, and 70 degrees on each side of the subject, with near additions of +1.50 D, +2.50 D, and no addition. We found no significant effect of monovision correction on peripheral visual acuity. In the second experiment we measured the peripheral visual acuity of 11 presbyopic subjects wearing distance contact lenses with lookover spectacles, soft progressive bifocal contact lenses, soft concentric bifocal contact lenses, monovision contact lenses, modified monovision contact lenses, and hard bifocal contact lenses using Koenig bar targets. There were no significant differences in peripheral visual acuity between any of the contact lens corrections for presbyopia.     

Comparison of multifocal and monovision soft contact lens corrections in patients with low-astigmatic presbyopia.

PURPOSE: The purpose of this study was to assess visual performance and patient satisfaction with two presbyopic soft contact lens modalities. METHODS: A crossover study of 38 patients with presbyopia was conducted. Patients were randomized first into either multifocal (Bausch & Lomb SofLens Multifocal) or monovision (SofLens 59) for 1 month. Visual performance was measured with high- and low-contrast visual acuity at distance and near and near stereoacuity. Patients' satisfaction was measured by the National Eye Institute Refractive Error Quality of Life Instrument questionnaire and by recording the patient's final lens preference. RESULTS: Patients maintained at least 20/20 binocular vision with both multifocal (MF) and monovision (MV) contact lenses under high-contrast conditions at distance and near. Under low-contrast conditions, patients lost less than a line of vision from the best spectacle correction to either multifocal or monovision contact lens correction at distance (pMF = 0.001, pMV = 0.006). Under low-contrast conditions at near, multifocal wearers lost five to six letters and monovision wearers lost two letters of vision (pMF < 0.001, pMV = 0.03, pMF/MV = 0.005). The average stereoacuity decreased by 79 s arc with monovision vs. multifocal contact lenses (p = 0.002). On the NEI-RQL, patients reported worse clarity of vision (pMF = 0.01, pMV < 0.001), more symptoms (pMF = 0.09, pMV = 0.01), and an improvement in their appearance with contact lens wear (pMF < 0.001, pMV < 0.001). Seventy-six percent of patients reported that they preferred multifocal contact lenses, and 24% preferred monovision contact lenses (p = 0.001). CONCLUSION: The majority of our patients preferred multifocals to monovision, most likely because the Bausch & Lomb SofLens Multifocal provides excellent visual acuity without compromising stereoacuity to the same degree as monovision.     

单眼视LASIK治疗伴有老视的屈光不正临床观察

目的:探讨单眼视准分子激光原位角膜磨镶术(单眼视LASIK)治疗伴有老视的屈光不正对患者视觉质量、生活质量的影响。方法:屈光不正伴老视的患者172例中124例施行单眼视LASIK(主视眼按最佳矫正远视力完全矫正,非主视眼近视者低矫-0.75~-2.00D,远视者过矫0.75~2.00D),35例放弃手术,13例患者双眼全部矫正。观察术后1d;1wk;3mo时的检查结果。结果:术后3mo单眼视LASIK组124例患者双眼远视力0.7~1.2,双眼近视力J1~J3。无因为难以耐受的不适而需要戴镜补充矫正或再次手术者。双眼完全矫正组术后双眼远视力0.7~1.2,双眼近视力J3~J6,8例(62%)视近困难,需配近用眼镜。结论:单眼视LASIK治疗伴有老视的屈光不正安全有效。单眼视治疗在设计手术方案时需根据患者年龄及调节能力、近附加度数、阅读距离、工作性质等综合考虑。     

两种新型多功能人工晶状体矫正老视的疗效比较

目的:比较双焦点人工晶状体(AtLisa tri 809MP)与三焦点人工晶状体(AtLisa tri 839MP)植入术后矫正老视疗效的差异。方法:纳入于我院行白内障超声乳化吸除联合人工晶状体植入术的患者共40例51眼进行分析,其中A组20例25眼植入809MP双焦点人工晶状体,B组20例26眼植入839MP三焦点人工晶状体。收集两组患者术后3mo时远中近视力数值、离焦曲线分析,并通过满意度调查问卷进行统计分析。结果:术后3mo两组裸眼远视力与最佳矫正视力均无差异(P>0.05);中距离视力(80cm)B组显著优于A组(P<0.01);近距离视力改善程度A组、B组无差异(P>0.05)。术后3mo离焦曲线结果A组在0、-3D处形成2个波峰;B组在0、-2.5D处形成2个波峰;两组患者术后均有不同程度的眩光、光晕等表现,但总体满意度较高,视近满意度较高。结论:两种类型人工晶状体均可以为患者提供兼顾远、近的全程视力,术后近距离视物脱镜率高,均可提高良好的近距离视力,三焦点人工晶状体中距离视力更好。     

Clinical performance of an innovative back surface multifocal contact lens in correcting presbyopia.

PURPOSE: This prospective study was designed to subjectively and objectively evaluate the performance of an aspheric multifocal back surface rigid gas permeable (RGP) contact lens. The multifocal element of this lens design consisted of an aspheric optical zone that varied according to the patient's ametropia, corneal topography, and required reading addition. METHODS: We fit 28 presbyopic subjects with an aspheric multifocal back surface RGP contact lens (age range: 45 to 68 years). Reading additions ranged from +0.75 D to +2.50 D. Subjects were assessed initially and at 2, 6, and 12 weeks for ocular changes, visual performance, and subjective responses. RESULTS: We required 116 RGP lenses to achieve an acceptable fit and visual acuity in 28 subjects (55 eyes). At the final visit, the distance logMAR acuity with the multifocal contact lens (+0.12 +/- 0.10) was not statistically different (t = -0.623, P = -0.5388) from spectacle acuity at the initial visit (+0.10 +/- 0.12). The near logMAR acuity with the multifocal contact lens at the final visit (0.36 +/- 0.12) was not statistically different from that for near acuity with spectacles at the initial visit (0.33 +/- 0.13). No slit lamp signs worsened during the study. A reduction in myopia of 0.67 D was noted by the final visit. Spectacle blur was noted if the acuity at the initial refraction was compared to the acuity with the same refraction at the final visit (t = -3.287, P = 0.0028) but not when the refractive changes were incorporated (t = 1.058, P = 0.3127). All subjects rated the performance of the lenses very highly: comfort, 86%; distance acuity, 83%; near acuity, 73%; and stability of vision, 74%. Twenty-four subjects (86%) chose the multifocal contact lens as their preference. CONCLUSION: We demonstrated that a multifocal design is able to provide acceptable distance and near correction for presbyopic patients. The aspheric geometry required can be optimized for a given patient by considering his/her degree of ametropia, as well as the corneal topography.     

CK和LASIK治疗老视的临床效果对比研究

目的:比较分析传导性角膜成形术(conductive keratoplas-ty,CK)和准分子激光原位角膜磨镶术(laser in situ kera-tomileusis,LASIK)应用单眼视治疗老视的临床效果和视觉质量。方法:21例(26眼)及24例(41眼)老视患者分别接受CK和LASIK治疗,术前患者屈光度球镜+0.75~+2.0D,散光≤+0.75D,术后预期目标屈光度主导眼矫正为0~-0.5D,非主导眼矫正为-1.5~-2.5D近视状态且近视力≥0.5(J3),术后随访1a。结果:术后1aCK组和LASIK组双眼裸眼视力≥0.8且近视力≥J3者分别为52.4%、66.7%,近视力≥0.33(J4)者分别为81.0%、87.5%,两组与术前相比均有显著性差异(P<0.01),两组间相比较无显著性差异(P>0.05);术眼等效球镜屈光度与预期目标相差±0.5D以内者分别为42.3%、70.7%,两组相比较差异有显著性(P<0.05);术眼散光度在±0.75D以内者分别为57.7%、92.7%,两组相比较差异有显著性(P<0.05);术眼角膜光学视功能区CK组和LASIK组相比较无显著性差异;两组患者术眼对比敏感度较术前均无明显下降;术后1a患者术眼有干眼症状者CK组为3眼(11.5%),LASIK组为8眼(19.5%),两组相比较无显著性差异(P>0.05)。结论:应用单眼视原理采用CK和LASIK治疗老视均取得了较满意的疗效,两种手术方式的远期疗效和稳定性有待进一步观察。