Monovision矫正方法在屈光手术中的应用

MV矫正 (monovision)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 ,可分为常规MV和交叉性MV两种类型 ,其机制是双眼间的模糊抑制。MV可应用于屈光手术 (PRK、LASIK、人工晶状体植入 )中。本文回顾有关文献 ,探讨MV矫正的视力效果、对双眼视功能的影响和影响矫正成功的因素     

M0novision矫正方法在屈光手术中的应用

MV矫正(monovision)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，可分为常规MV和交叉性MV两种类型，其机制是双眼间的模糊抑制。MV可应用于屈光手术(PRK、LASIK、人工晶状体植入)中。本文回顾有关文献，探讨MV矫正的视力效果、对双眼视功能的影响和影响矫正成功的因素。     

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.     

手术治疗老视

随着人类社会的老龄化 ,老视的困扰给中老年人带来诸多不便 ,中老年人对老视的治疗有了更高的要求 ,人们希望不戴镜便能矫正老视。世界各地的学者已开始探讨通过手术矫正老视。一、Monovision矫正老视(一 )适应症与影响因素 :MV成功基于两眼间的模糊抑制 ,理想的MV双眼清晰视力范围应等于单眼之和 ,不受另一眼模糊影像干扰〔1〕。MV可通过CL实现 ,通过屈光手术诸如PRK ,LASIK ,RK ,PTK ,晶体摘除合并人工晶体植入〔1～ 4〕,以MV方式矫正老视也可行 ,一般认为以MVCL矫正 ,待确定其MV适应性后再作手术可提高成功率〔5〕。MV对于…     

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矫正屈光不正的应用

Monovision(MV)矫正方法以往常用于老视和老视前期患者,即1眼矫正视远,另1眼矫正视近,其机制是双眼间的模糊抑制。近几年也用于中年近视的矫正。我们就MV矫正的机制、应用方式、对双眼视功能的影响以及研究进展作一综述。     

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。     

老视的角膜矫正手术

老视是随着年龄增长、调节能力丧失出现视近物困难的一种生理现象,发病机制尚不明确。人口老龄化使老视人口及老视矫正的需求逐渐增多,老视的手术矫正方法正成为眼科医师关注的热点。随着技术和材料的不断发展,出现了多样化的老视矫正手术,包括经角膜老视矫正手术、晶状体老视矫正手术和巩膜老视矫正手术。尽管还没有一种完美的老视矫正手术能真正恢复眼的调节功能,现有的手术已取得一些临床效果。现对老视的角膜手术矫正方法做一综述。     

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。     

Strabisme Alternant - Etude clinique - traitement

The author defines motor and sensory alternation: the term alternation should not be used in isolation, it should always be accompanied by the name of the parameter concerned. Sensory alternation is always found together with motor alternation but the reverse is not true.The examining criteria for a diagnosis of sensory alternation are given, sensory alternation must not be confused with alternating inhibition. Working from clinical observations of cases of motor alternating strabismus, the author selects 2 types of binocular sensory relations which allow one to differentiate between:- cases of primary alternating strabismus- cases of secondary alternating strabismusThese forms will develop in different ways; in both cases a cure is possible providing that the right treatment is prescribed and once prescribed carefully followed, etc. It is always a case of serious forms of strabismus whose developmental period is spread over several years.According to the authors, the frequency of cases of true primary strabismus is from 1–3%, the frequency of cases of secondary alternating strabismus varies according to the type of therapy practised on cases of monocular strabismus with amblyopia. These latter will become cases of alternating strabismus under the influence of certain types of therapy carried out over several years (penalization, rocking, alternated occlusion, etc...).Experimental data on kittens confirm clinical data; kittens placed in abnormal environments during the sensitive period will show modification in the distribution of cortical cells and the absence of binocular cells (either because the excitation of the two eyes was not simultaneous, or not identical: artificial strabismus, occlusion, opaque glasses). This disturbances become irreversible after a certain period of exposure (a function of age, length of exposure, etc...).It is thus necessary to bear in mind: 1) the iatrogenic risks of certain orthoptic treatments, 2) the necessity for a binocular form of treatment as soon as possible, as once a certain stage is passed, cortical plasticity diminishes and the elaboration of normal binocular relations becomes impossible.

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Effects of Adenosine Agonists on Intraocular Pressure and Aqueous Humor Dynamics in Cynomolgus Monkeys

The effects of single or multiple topical doses of the relatively selective A₁adenosine receptor agonists (R)-phenylisopropyladenosine (R-PIA) and N⁶-cyclohexyladenosine (CHA) on intraocular pressure (IOP), aqueous humor flow (AHF) and outflow facility were investigated in ocular normotensive cynomolgus monkeys. IOP and AHF were determined, under ketamine anesthesia, by Goldmann applanation tonometry and fluorophotometry, respectively. Total outflow facility was determined by anterior chamber perfusion under pentobarbital anesthesia. A single unilateral topical application of R-PIA (20–250 μg) or CHA (20–500 μg) produced ocular hypertension (maximum rise=4.9 or 3.5 mmHg) within 30 min, followed by ocular hypotension (maximum fall=2.1 or 3.6 mmHg) from 2–6 hr. The relatively selective adenosine A₂antagonist 3,7-dimethyl-1-propargylxanthine (DMPX, 320 μg) inhibited the early hypertension, without influencing the hypotension. Neither 100 μg R-PIA nor 500 μg CHA clearly altered AHF. Total outflow facility was increased by 71% 3 hr after 100 μg R-PIA. In conclusion, the early ocular hypertension produced by topical adenosine agonists in cynomolgus monkeys is associated with the activation of adenosine A₂receptors, while the subsequent hypotension appears to be mediated by adenosine A₁receptors and results primarily from increased outflow facility.